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2012International Conference
St. Simons Island, Georgia, USAOctober 30 - November 2
Hosted by:
Program Committee Members
Alison Buchan Department of Microbiology The University of Tennessee
Mark DavisNational Renewable Energy Laboratory
Mario EdenAuburn University
Claus FelbyUniversity of Copenhagen
Maureen McCannPurdue University
Jonathan MielenzOak Ridge National Laboratory
Brent ShanksIowa State University
Christian StevensGhent University
Steering Committee Members
Joseph Bozell Center for Renewable Carbon The University of Tennessee
Nicole LabbéCenter for Renewable Carbon The University of Tennessee
Peter MullerPerkin-Elmer, Inc.
Timothy RialsCenter for Renewable Carbon The University of Tennessee
Registration/Social Hour
Registration
CONFERENCE SCHEDULE
TUESDAY OCTOBER 30, 2012
WEDNESDAY OCTOBER 31, 2012
5:00-8:00pm
WEDNESDAY OCTOBER 31, 2012
Session 2A: From Pretreatment to Fractionation Moderator: Percival Zhang (Virginia Tech)
1:30-1:55 Julie Carrier (University of Arkansas - Biomass into Bioproducts)
1:55-2:20 Maobing Tu (Auburn University - Enzymatic Hydrolysis of Ethanol Organosolv Pretreated Loblolly Pine and Sweetgum)
2:20-2:45 Nancy Nichols (USDA - National Center for Agricultural Utilization Research - A Biological Approach to Cleaning up Fermentation Inhibitors Present in Biomass Sugars)
2:45-3:10 John Yarbrough (National Renewable Energy Laboratory - Understanding Biomass Recalcitrance Using Advanced Imaging)
Coffee Break
3:30-3:55 Adriaan van Heiningen (University of Maine - Biobutanol from Forest Residues by SO
2 Ethanol-Water
Fractionation and ABE Fermentation)
3:55-4:20 Scott Renneckar (Virginia Tech - “Melt-Compounded” Biomass: A Unique Pretreatment for Cellulose Saccharification and Lignin Extraction)
4:20-4:45 Rashmi Kataria (Trinity College Dublin - Effect of Surfactants Pre-Treatment on Lignocellulosic Biomass)
Session 2B: Chemical Catalysis Moderator: Laura Jarboe (Iowa State University)
1:30-1:55 Roberto Rinaldi (Max Planck Institute - Mechano–Catalytic Depolymerization of Cellulose)
1:55-2:20 Michel Delmas (University of Toulouse - The BBB Process: Biomass to Biofuels and Bioproducts)
Coffee Break
3:30-3:55 Peter Miedziak (Cardiff University - The Use of Platinum Alloyed Bimetallic Catalysts to Manipulate Product Distributions During the Oxidation of Polyols)
3:55-4:20 Doug Hayes (University of Tennessee - Biobased Surfactants: A Useful Biorefinery Product That Can Be Prepared Using Green Manufacturing)
4:20-4:45 Sabornie Chatterjee (Oak Ridge National Laboratory - Preparation and Characterization of Modified Lignin for the Production of Carbon Fibers)
7:00-7:50am Breakfast and Welcome
Plenary Session: Biorefinery Concepts for Chemicals and Products Moderator: Liam Leighlty (Institute for Advanced Learning and Research)
7:50-8:00 Welcome and Opening Remarks - Timothy Rials (University of Tennessee)
8:00-8:40 Gregg Beckham (National Renewable Energy Laboratory – Computational Modeling of Biomass Conversion Systems)
8:40-9:20 Clint Chapple (Purdue University – Manipulation of Lignin Biosynthesis in Plants: The Low Hanging Fruit in Feedstock Improvement for the Biorefinery)
9:20-10:00 Percival Zhang (Virginia Tech – Innovative Biomanufacturing Platform: Cell-Free Synthetic Pathway Biotransformation)
10:00-10:15am Coffee Break
10:15-10:55 Gary Peter (University of Florida – High Terpene Pines: Transforming Existing and Enabling New Forest Biorefineries)
10:55-11:35 Claus Felby (University of Copenhagen – Biorefinery Development: The Danish Perspective)
11:35-12:15 Joe Bozel (University of Tennessee – Integrating Separation and Conversion – Transforming Biorefinery Process Streams to Biobased Chemicals and Fuels)
12:15 - 1:30pm Lunch Timothy G. Rials (University of Tennessee – Introduction to IBSS, Southeastern Partnership for Integrated Biomass Supply Systems)
6:30-8:30pm
7:30-8:30am Breakfast
Session 3A: Biocatalytic Conversion Moderator: Claus Felby (University of Copenhagen)
8:30-8:55 Cong Trinh (University of Tennessee - Redesigning E.coli Metabolism for Obligate Anaerobic Production of Biofuels and Biochemicals)
8:55-9:20 Hugh O’Neill (Oak Ridge National Laboratory - Investigation of Structural Changes in Cel7A Cellulase when Bound to Cellulose Substrates)
9:20-9:45 Jason Sello (Brown University - Genetic Engineering of Streptomyces Bacteria as Lignocellulose Biorefineries)
Coffee Break
10:30-10:55 Birgitte Ahring (Washington State University - Producing Drop-In Hydrocarbon Biofuels from Lignocellulosic Biomass Materials)
10:55-11:20 Hossein Noureddini (University of Nebraska Lincoln - Cellulase Production by Solid State Fermentation on Wet Corn Distillers Grains)
11:20-11:45 Christian Stevens (Ghent University – Exploiting Nature’s Diversity for the Development of Chemical Building Blocks)
11:45-12:10 Reeta Davis (University College Dublin - Conversion of Cellulosic Biomass from Grass into Fermentable Sugars and its Effective Utilization for Biosynthesis of Medium Chain Length Polyhydroxyalkanoates (MCL-PHA) by Pseudomonas SPP)
Session 3B: Advances in Analytical Techniques and Computational Processes
Moderator: Peter Muller (Perkin Elmer)
8:30-8:55 Laurene Tetard (Oak Ridge National Laboratory - Surface and Subsurface Physical and Chemical Characterization of Soft Materials at the Nanoscale)
8:55-9:20 Laura Jarboe (Iowa State University - Enabling Robust Production of Biorenewable Fuels and Chemicals from Biomass)
9:20-9:45 Hilkka Kenttämaa (Purdue University - Tandem Mass Spectrometry in the Characterization of Converted Biomass)
Coffee Break
10:30-10:55 Thomas Elder (USDA Forest Service Southern Research Station - Applications of Computational Chemistry to the Reactions of Lignin)
10:55-11:20 Gnana Gnanakaran (Los Alamos National Laboratory - Overcoming Recalcitrance of Biobased Feedstocks Through Catalytic Conversions)
11:20-11:45 Ariana Beste (University of Tennessee - Lignin Model Pyrolysis: A Computational Approach)
11:45-12:10 Anis Khimani (Perkin-Elmer - From Paper Trails to Electronic Management Systems: Green Lining the Biomass Conversion Process)
WEDNESDAY OCTOBER 31, 2012
Poster Session
THURSDAY NOVEMBER 1, 2012
Free Time
Social Hour / Conference Dinner and Keynote Speaker
THURSDAY NOVEMBER 1, 2012
THURSDAY NOVEMBER 1, 2012
6:00-7:00pm - Social Hour
7:00-9:00pm - Dinner
Guliz Elliott - Chemtex International, Inc. - Lignin Rich Residues from Biomass to Chemicals and Fuels
FRIDAY NOVEMBER 2, 2012
7:30-8:30am Breakfast
Session 4A: Chemical Processes Moderator: Gregg Beckham (National Renewable Energy Laboratory)
8:30-8:55 Roberto Rinaldi (Max-Planck Institute - Solvent-Based Catalytic Strategies for the Selective Hydrogenolysis of Lignin and Selective Defunctionalization of Bio-0il Under Low- Severity Conditions)
8:55-9:20 Doug Hendry (University of Missouri - High Throughput Biomass Conversion in Supercritical Water and Product Separations as an “End of Pipe” Technology in a Biomass Refinery)
9:20-9:45 David Johnson (National Renewable Energy Laboratory - Conversion of Sugars to Hydrocarbons via Depolymerization and Decarboxylation of Polyhydroxyalkanoates)
Coffee Break
10:30-10:55 Darren Baker (University of Tennessee - Carbon Fiber from Engineered Lignin)
10:55-11:20 Nicole Brown (Pennsylvania State University - Pyrolysis of Lignin to Create a New Foundry Fuel Source)
11:20-11:45 Mahdi Abu-Omar (Purdue University - Cheap and Abundant Catalysts for Biomass Conversion Including Lignin)
Session 4B: Industrial Processes Moderator: Barry Goodell (Virginia Tech)
8:30-8:55 Orlando Rojas (North Carolina State University - New Technologies for Wood Pretreatment within the Concept of the Biorefinery and Novel Uses of Cell Wall Components)
8:55-9:20 Hideki Abe (Tokyo Institute of Technology - Biosynthesis and Characterization of Medium-Chain-Length Poly (3-Hydroxyalkanoates)
9:20-9:45 Foster Agblevor (Utah State University - Production of High - Valued Chemicals from Fractional Catalytic Pyrolysis of Biomass)
Coffee Break
10:30-10:55 David Nielsen (Arizona State University - Engineering Bacteria to Produce Bio-Styrene and Other Aromatic Chemicals)
10:55-11:20 John Bhatt (Novasep - Advanced Purification Technologies for your BioBased Chemicals)
WEDNESDAY OCTOBER 31, 2012
6:30-8:30pm
Poster Session
Louise Ahl - University of Copenhagen - Carbohydrate Microarrays for Measuring Cell Wall Polysaccharides in Relation to Biomass Conversion
Julio Arboleda - North Carolina State University - Synthesis and Characterization of Novel Soy Protein-Nanocellulose Composite Aerogels
Frank Armstead - Auburn University - Biomass Characterization and Gasification for Transportation Fuels Production
Anton Astner - University of Tennessee - Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design Using Organosolv Fractionation
Priyanka Bhattacharya - University of Tennessee - Screening of Lignins by Pyrolysis-Gas Chromatography/Mass Spectrometry
Christine Bohn - Purdue University - Dehydration of Plant Derived Sugars Utilizing Iron (III) and Molybdenum (V) Catalysts in a Biphasic Reaction Medium
Federico Cerrone - Trinity College Dublin - Conversion of Anaerobic Digested Grass into PHAs by High Cell Density Fermentation Strategies
William Chaplow - Auburn University - Dilute Acid and Organosolv Pretreatment of Loblolly Pine and Sweetgum
Jennifer Davis - Brown University - Study of PcaV from Streptomyces Coelicolor Yields New Insights into Ligand-Responsive MarR Family Transcription Factors
Paul Filson - University of Tennessee - Investigation of Potential Inhibitors from Switchgrass in Biorefinery
Doug Hayes - University of Tennessee - Preparation of Oligo Ricinoleic Acid Derivatives via Lipase-Catalyzed Esterification as Lubricant Additives and Star Polymers for Drug Delivery
Doug Hayes – University of Tennessee - Poly (Lactic Acid)/Poly (Hydroxyalkanoate) Nonwovens as Biodegradable Agricultural Mulches
Ingrid Hoeger - North Carolina State University - Influence of Feedstock Deconstruction in Enzymatic Saccharification of Softwoods
Omid Hosseinaei – University of Tennessee - Oxidative Stabilization Studies in the Formation of Electrospun Carhon Nanofibers from a Purified Softwood Kraft Lignin
Tiffany Jarrell – Purdue University - Characterization of Organosolv Switchgrass by High Performance Liquid Chromatography/Multiple State Tandem Mass Spectrometry Using Hydroxide-Doped Electrospray Ionization
Pyoungchung Kim - University of Tennessee - The Effects of Organosolv Fractionation Process on the Properties of Switchgrass Lignin as a Precursor for Carbon Products
Lindsey Kline - University of Tennessee - Activation of Lignocellulosic Biomass in Ionic Liquids
Christopher Marcum - Purdue University - A Fundamental Study of the Fragmentation of Small Molecules Related to Lignin via Collision-Activated Dissociation (CAD)
James Riedeman - Purdue University - Methods for the Identification of levoglucosan Isomers in Bio Oil Obtained by Fast Pyrolysis of Cellulose
Carlos Salas - North Carolina State University - Lignin-Soy Protein Interactions: Electrospun Nanofibers Based on Soy Proteins and Lignin
Kelvin Smith - Auburn University - Rapid Characterization and Determination of Wood Chemistry and Crystallinity Index of Loblolly Pine
Trevor Treasure - North Carolina State University - Integrated Process, Financial, and Risk Modeling of Cellulosic Ethanol From Woody and Non-Woody Feedstocks via Dilute Acid Pretreatment
Jacob Wadkins - Auburn University - Flowability of Ground Loblolly Pine
Liana Wuchte - Auburn University - Gas-Phase Higher Alcohol Synthesis and Fischer Tropsch Synthesis
Wei Zhang - Virginia Tech - Analysis of Novel Lignin Extracted from “Melt Compounded” Biomass
THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF LIGNIN UTILIZATION
Gregg T. Beckham, Mary J. Biddy, Stephen C. Chmely, Rui Katahira, Seonah Kim, Erik M. Kuhn, Matthew R. Sturgeon, and Thomas D. Foust
National Renewable Energy Laboratory
1617 Cole Blvd MS 3322 Golden, CO, USA
Lignin is an energy-dense, heterogeneous, alkyl-aromatic polymer that imparts significant resistance to enzymatic
degradation of plant biomass. In selective biomass conversion strategies to fuels, such as thermochemical
pretreatment, enzymatic hydrolysis, and fermentation to ethanol, lignin is typically burned for heat and power, and in
pyrolytic biomass conversion strategies, lignin is thought to contributes to the detrimental reactivity of resulting bio-
oils. To understand how to utilize lignin in a more selective manner, our group uses experimental methods in concert
with quantum mechanical calculations to understand lignin deconstruction via thermal, catalytic, and enzymatic
processes. This talk will describe the general methodologies used in our group. Several studies will be presented in
detail including the elucidation of a multi-step catalytic cycle of a ruthenium-based xantphos catalyst for reductive
cleavage of aryl-ether bonds, efforts in characterizing and deconstructing lignin derived from fractionation processes,
and the deconstruction of lignin in acidic media. Additionally, results will be presented from recent techno-economic
and life-cycle analyses that aid in defining the minimum required economic and process parameters for lignin
conversion to fuels and chemicals.
MANIPULATION OF LIGNIN BIOSYNTHESIS IN PLANTS: THE LOW HANGING FRUIT IN FEEDSTOCK IMPROVEMENT FOR THE BIOREFINERY
Clint Chapple
Department of Biochemistry, Purdue University 175 South University Street
West Lafayette, Indiana, USA
Increasing awareness of the impact of global greenhouse gas emissions, dwindling petroleum reserves, and concerns
with regard to energy security have led to a dramatic increase in interest in the development of renewable, cellulose-
based sources of biofuels. Lignin stands as a significant barrier to this goal because it interferes with the utilization of
lignocellulosic biomass. Efforts aimed at decreasing lignin deposition show promise for improving biomass conversion
efficiency, but considering that lignin is essential to plant viability, it is clear that novel approaches to the modification
of lignin will be required to make efficient cellulose-based biofuel production a reality.
Unlike all other biological polymers, lignin synthesis is not template-directed and the relative amounts of its
component monomers (monolignols) is determined solely by the ratios of the precursors synthesized by the lignifying
cell. This unique characteristic provides significant opportunity for the manipulation of the chemistry and architecture
of lignin in the cell wall because the manipulation of monolignol biosynthesis is all that is required to generate
dramatic and impactful changes in the lignin polymer. As a result, at least in model systems, plants with lignins
containing essentially solely p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) subunits have been generated,
frequently with significant impacts on the ease with which the polymers can be removed from the biomass and/or
biomass saccharification efficiency. These changes simultaneously decrease the complexity of lignin, thereby
opening the doors to more effective use of lignin degradation products in the biorefinery. In all cases to date, the
discoveries made in model systems have been faithfully recapitulated in genuine biomass feedstocks, demonstrating
that translation of these discoveries from the lab to the field can be expected to impact the biorefinery in the near
term.
INNOVATIVE BIOMANUFACTURING PLATFORM: CELL-FREE SYNTHETIC PATHWAY BIOTRANSFORMATION
Y.-H. Percival Zhang, Ph.D.1,2,3
1 Biological Systems Engineering Department, Virginia Polytechnic Institute and State University (Virginia Tech), 210-
A Seitz Hall, Blacksburg, Virginia 24061, USA 2 Institute for Critical Technology and Applied Science (ICTAS), Virginia Polytechnic Institute and State University,
Blacksburg, Virginia 24061, USA 3 Gate Fuels Inc. 2200 Kraft Drive, Blacksburg, VA 24060, USA
Cell-free synthetic pathway biotransformation (SyPaB) (1, 2) is the implementation of complicated reactions that
microbes and chemical catalysts cannot through the in vitro assembly of numerous (stable) enzymes originated from
different sources and/or (biomimetic) cofactors. SyPaB features numerous advantages: high product yield, fast
reaction rate, easy access and control for open systems, tolerance of toxic compounds, broad reaction conditions,
and so on.
In this talk, I will introduce the basic concept of SyPaB and present several applications: (i) the highest yield hydrogen
production from sugars (i.e., an out-of-the-box solution to the hydrogen economy) (3, 4), (ii) enzymatic
biotransformation of cellulose to high-value amylose (i.e., feeding the world by providing high quality (tailored) food),
(iii) enzymatic fuel cells (i.e., high-energy density biobatteries) (5), (iv) highest-energy retaining production of jet fuel
through a hybrid of SyPaB and catalysis (6), and (iv) artificial photosynthesis for CO2 utilization (7). Also, I will talk
about some of our efforts in developing basic building blocks (e.g., thermoenzymes), building modules (e.g., synthetic
metabolons) (8), and redox enzyme engineering. SyPaB would become a high-yield and low-cost biomanufacturing
platform and lead a paradigm shift, especially in white biotechnology and biorefineries.
References 1. Zhang Y-HP. 2010. Biotechnol. Bioeng. 105: 663-77 2. Zhang Y-HP, Myung S, You C, Zhu ZG, Rollin J. 2011. J. Mater. Chem. 21: 18877-86 3. Ye X, Wang Y, Hopkins RC, Adams MWW, Evans BR, et al. 2009. ChemSusChem 2: 149-52 4. Zhang Y-HP, Evans BR, Mielenz JR, Hopkins RC, Adams MWW. 2007. PLoS One 2: e456 5. Zhu ZG, Sun F, Zhang X, Zhang Y-HP. 2012. Biosens. Bioelectron. 36: 110-5 6. Wang Y, Huang W, Sathitsuksanoh N, Zhu Z, Zhang Y-HP. 2011. Chem. Biol. 18: 372-80 7. Zhang Y-HP, Huang W-D. 2012. Trends Biotechnol. 30: 301-6 8. You C, Myung S, Zhang Y-HP. 2012. Angew. Chem. Int. Ed.: Epub, DOI: 10.1002/anie.201202441
HIGH TERPENE PINES: TRANSFORMING EXISTING AND ENABLING NEW FOREST BIOREFINERIES
Gary F. Peter1, Hemant Patel1, John M. Davis1, Mark Davis2, Maud Hinchee3, James Kirby4, Pamela Peralta-Yayha4,
Blake Simmons4, Jay Keasling4
1School of Forest Resources and Conservation, Plant Molecular and Cellular Biology Program
University of Florida PO Box 110410, Gainesville, FL USA
2National Renewable Energy Laboratory, Golden, CO, USA 3ArborGen, 2011 Broadbank, Ct., Ridgeville, SC, 29472
4University of California, Berkeley, 5885 Hollis St. Emeryville, CA, USA
Forest biorefineries are one of the oldest and still the best examples of processing lignocellulose rich biomass to a
wide array of renewable chemical and biomaterial products. For example in the US south, Kraft linerboard facilities
breakdown wood from southern pine and hardwoods into fibrous pulp which is used to make base and top ply sheets
for cardboard boxes, and the extracted liquor containing lignin, carbohydrates, fatty acids, and terpenes, are
concentrated and separated prior to recovery of the inorganic pulping chemicals. While the lignin and carbohydrates
are currently burned for energy, the hydrocarbon rich monoterpenes are recovered from the top of the digester as
crude sulfated turpentine (CST) and fatty acids, diterpenes, and unsaponafiables are recovered from the spent
pulping liquor as crude tall oil (CTO) soaps. CST and CTO co-products are sold to pine oleochemical refiners for
separation and upgrading into a diverse set of products. Globally, pine oleochemicals are a >$3 billion annual
market, that is limited by CST and CTO supply. CST and CTO yields are limited primarily by the extractive content of
pine wood, which averages 3-5% of the dry weight. We are developing high terpene southern pine trees to
dramatically boost recovery of CST and CTO for the existing pine oleochemical industry as well as to supply
advanced drop-in biofuels suitable for jets, ships and cars. Justification for development of high terpene pines and
the potential impact on Kraft linerboard mill production and economics as a case study will be presented together with
other possible alternative configurations of forest biorefineries that could maximize production of pine oleochemicals
and value from pine lignocellulose.
BIOREFINERY DEVELOPMENT – THE DANISH PERSPECTIVE
Claus Felby
Faculty of Science University of Copenhagen
Rolighedsvej 23, 1958 Frederiksberg, Denmark
For more than 25 years biomass has been part of the Danish energy system. The technology has now developed to a
level where large-scale biorefineries will be build. A number of conversion technologies are involved in the refinery
design including cellulosic ethanol, biogas, gasification and hydrogenation. A main issue is the integration and
synergy between the different technologies and how they link to already established infrastructures in the energy-,
chemical- and agricultural sector.
The presentation will provide an overview of the technology development including some of the breakthroughs made
possible by the scaling from laboratory to pilot- and demonstration scale. Another issue is the biomass supply. The
approach taken is to use and develop already available biomass from existing agriculture and forestry, rather than
building a separate supply from bioenergy crops. This has a number of advantages in terms of sustainability and
economy.
The last issue in the presentation will touch upon the European political perspectives of a biorefinery sector.
Biorefineries are not just technology; they are also part of a supply security and a rural economy. Thus job creation,
supply levels and the need for economic incentives plays a large role in the political decisions needed for securing
long-term investments in the sector.
BIOMASS INTO BIOPRODUCTS
Danielle Julie Carrier
Biological and Agricultural Engineering University of Arkansas
203 White Hall, Faytteville, AR 720701
Tree bark is usually not considered an ideal candidate for biorefinery feedstock, mainly because it is not a substantial
source of carbohydrate compared to tree wood. However, using the whole tree would simplify supply chain
processing and conversion. Although dilute acid pretreatment is corrosive, it is emerging as one of the leading
chemical pretreatments. When sweetgum bark (Liquidambar styraciflua L.) is pretreated in non-stirred reactors at
160°C for 60 min in 1% (v/v) sulfuric acid, 10 and 139 mg per g of biomass of glucose and xylose, respectively, were
recovered. If sweetgum bark was soaked at 85 °C for 18 h prior to pretreatment as described, 15 and 105 mg per g of
biomass of glucose and xylose, respectively, were recovered. Soaking the bark prior to pretreatment increased
glucose recovery. In addition to aiding in the recovery of glucose, soaking the biomass prior to pretreatment,
decreased inhibitory compound formation. The soaking process reduced formic acid concentrations by 28% in the
hydrolysates and wash waters. Reducing the concentration of xylose prior to pretreatment may be more important
than initially anticipated due to the likeliness of xylose degrading to formic acid. The degradation rate constant from
xylose to furfural and from xylose to formic acid was calculated as 0.0128 and 0.0235 min-1, respectively, indicating a
preference for formic acid accumulation. Formic acid is a potent enzymatic hydrolysis inhibitor. Using Accellerase
®1500 with cellulose powder as substrate, addition of 5 or 10 mg/mL formic acid reduced glucose recovery by 34%
and 81%, respectively, in comparison to the control.
In addition to the advantage of decreasing formic acid concentrations, soaking waters may contain value added
compounds that could warrant this extra step. Soaking water, reconstituted in dimethyl sulfoxide, inhibited low density
lipoprotein oxidation activity, demonstrated through the thiobarbituric reactive substances (TBARS) assay, at
concentrations of 12.5 mg bark extract per ml of or higher. Although unknown at this point, these results suggest that
there may be biologically active compounds that could be worth extracting from the soaking waters.
In conclusion, results indicate that while the use of bark may be problematic, especially in terms of formic acid
formation, the accumulation of this inhibitor could be circumvented by the implementation of a water soaking step
prior to pretreatment.
ENZYMATIC HYDROLYSIS OF ETHANOL ORGANOSOLV PRETREATED LOBLOLLY PINE AND SWEETGUM
Maobing Tu*a , Mi Lia, Sushil Adhikarib
aAuburn University
Forest Products Lab and Center for Bioenergy and Bioproducts 520 Devall Drive
Auburn, AL, 36849, U.S.
bAuburn University Department of Biosystems Engineering
Auburn, AL, 36849, U.S.
The interaction between xylan/lignin and cellulase enzymes plays a key role in the effective hydrolysis of
lignocellulosic biomass. Elucidation of the distinct roles of residual xylan and lignin has been investigated in this
study. We pretreated loblolly pine (Pinus taeda) and sweetgum (Liquidambar styraciflua) in an ethanol organosolv
process and characterized the enzymatic hydrolysis of pretreated biomass quantitatively based on the initial
hydrolysis rates and the final hydrolysis yields. The initial hydrolysis rates of organosolv pretreated loblolly pine
(OPLP) and sweetgum (OPSG) were 1.45 g·L-1·h-1 and 1.19 g·L-1·h-1 under the enzyme loading of 20 FPU. The final
glucan hydrolysis yields of OPLP and OPSG at 72 h were 76.4% and 98.9% By correlating the amount of residual
lignin and xylan to the initial hydrolysis rate and the final hydrolysis yield in OPLP and OPSG, a more accurate
fundamental understanding of the roles of xylan and lignin in limiting the enzymatic hydrolysis has been developed.
The higher amount of residual xylan (9.7%) in OPSG resulted in lower initial hydrolysis rate (1.19 g·L-1·h-1). The higher
amount of residual lignin in OPLP (11.2%) resulted in lower final hydrolysis yield of glucan (76.4%). Apparently, xylan
was much closer to cellulose structurally than lignin, and consequently the initial interaction between xylan and
cellulases decreased the initial hydrolysis rate. The interaction between lignin and cellulases came later and affected
the final hydrolysis yield. The Langmuir adsorption isotherm between cellulases and pretreated substrates further
confirmed the distinct roles of residual xylan and lignin on enzyme affinity to the substrates. The addition of xylanase
could increase the initial hydrolysis rates from 60% to 67% in OPLP and from 89% to ~100% in OPSG under the
enzyme loading of 10 FPU. In addition, we observed in the simultaneous saccharification and fermentation (SSF) that
ethyl xyloside was produced by the enzymatic catalysis of xylose and ethanol.
A BIOLOGICAL APPROACH TO CLEANING UP FERMENTATION INHIBITORS PRESENT IN BIOMASS SUGARS
Nancy N. Nichols, Badal C. Saha, Bruce S. Dien, Michael A. Cotta
USDA National Center for Agricultural Utilization Research 1815 N. University St.
Peoria, IL, USA
A major constraint to conversion of biomass to value added-products is the presence, in the sugar stream, of
substances that are toxic to microbes. Inhibitory compounds including organic acids, phenolics, and furan compounds
arise during acid hydrolysis of biomass, and may cause a fermentation to stall or fail. However, the same compounds
that inhibit the fermenting microorganism can serve as a source of carbon and energy for other microbes, and so a
bioremediation strategy may be useful to detoxify the biomass sugars and allow conversion to end-product. Toward
this end, a soil isolate, an ascomycete fungus, was identified by selective screening and found to be uniquely suited
for mitigating fermentation inhibitors. The isolate, Coniochaeta ligniaria NRRL30616, metabolizes a wide range of
inhibitory compounds found in biomass dilute acid hydrolysates. During bioabatement using the fungal strain,
compounds from all classes of inhibitors were removed. Bioabatement using strain NRRL30616 was incorporated into
a fermentation scheme for converting biomass to ethanol. The bioabatement process has been evaluated for inhibitor
abatement prior to fermentations of crop residues and potential energy crops, and demonstrated in 100 liter
fermentations of wheat straw hydrolysate. Conditioning the pretreated hydolysate by inoculating with the fungal strain
prior to fermentation improves fermentability of the sugars.
BIOBUTANOL FROM FOREST RESIDUES BY SO2-ETHANOL-WATER FRACTIONATION AND ABE FERMENTATION
Adriaan van Heiningen1, 3, Minna Yamamoto1, Evangelos Sklavounos1, Mikhail Iakovlev, Shrikant Survase2, German Jurgens2,Kristian Melin2 and Tom Granström2
1 Department of Forest Products Technology, Aalto University, FI- 00076 AALTO, Finland 2 Department of Biotechnology and Chemical Technology, Aalto University, FI- 00076 AALTO, Finland
3 Department of Chemical and Biological Engineering, University of Maine, Jenness Hall, Orono, ME 04469, USA
A process for production of biobutanol from forest residues, such as branches, tree tops and stump wood, is
presented. It utilizes SO2-ethanol-water (SEW) fractionation, and fermentation of the sugars obtained by combining
the conditioned spent fractionation liquid and enzymatically hydrolysed cellulosic fibres. This Biorefinery concept is
called AVAPTM by American Process Inc.
It is demonstrated that the SEW technology using 50% (w/w) ethanol-water containing 12% (w/w) SO2 efficiently
fractionates both softwood (SW) and hardwood (HW) biomass in only 30 min at 150ºC temperature. Hemicellulose
sugars are dissolved in high yield (80%) in the spent fractionation liquor and of these up to 50% are in monomeric
form. Sugar degradation products are not formed in significant quantities due to the short treatment time.
Delignification is efficient, being 89% for HW biomass and 64% for SW biomass after only 20 min treatment.
The pulp fibers after SEW fractionation are washed to allow for high sugars recovery. The wash liquor is added to the
drained spent SEW liquor and the mixture is then evaporated under low pressure to recover the fractionation
chemicals. Ethanol removal is almost complete after vaporizing 2/3rd of the weight while most of the residual SO2 is
removed during subsequent steam stripping. Neutralization by liming with Ca(OH)2 is then employed to bring the
solution to a pH level suitable for fermentation. The liquor is then catalytically oxidized to convert any residual sulfite
ions to sulfate. Finally, the liquor is treated with resins to further remove lignin.
Cellulose in the fibers is enzymatically hydrolyzed to glucose. Glucose yields up to 95% are achieved for HW
cellulosic residues utilizing a commercial enzyme mixture at 3% enzyme dosage on substrate whereas the SW
residues are shown to require higher enzyme dosages. The differences in enzymatic digestibility are partially
explained by the chemical characteristics of these feed stocks.
Fermentation of the combined sugar stream has been successfully carried out using a patented fermentation column
technology where wood pulp is used as cell immobilization material for the Clostridium acetobutylicum strain. ABE
(Acetone, Butanol and Ethanol) solvent mixtures were produced at a productivity of almost 5 g/L/h and total yield of
0.27 g/g sugars.
Preliminary techno-economics for a 470 ktonne/year of biomass (dry basis) Biorefinery producing 61 ktonne/year of
butanol and other products indicates that this concept is profitable at industrial scale.
“MELT-COMPOUNDED” BIOMASS: A UNIQUE PRETREATMENT FOR CELLULOSE SACCHARIFICATION AND LIGNIN EXTRACTION
Scott Renneckar1,3, Wei Zhang1,3, Noppadon Sathitsuksanoh2, Justin R. Barone2,3, and Charles E. Frazier1,3
Departments of Sustainable Biomaterials1, Biological Systems Engineering2, and the Macromolecules and Interfaces
Institute3
Virginia Tech
230 Cheatham Hall Blacksburg, VA, USA
Accessing polysaccharides in the cell wall of lignocellulose biomass to generate cellulosic sugars for a bioeconomy is
a key challenge that has re-emerged over the past decade. A novel pretreatment method is described by combining
industrially proven polymer-processing equipment with a non-toxic solvent that plasticizes and disrupts the cell wall
structure. Particle size, temperature, and time are initial variables used to determine how these conditions affect
glucan digestibility of the biomass and yield of the extracted lignin. Milled sweet gum (Liquidambar styraciflua), a
candidate for short rotation woody crops, and milled corn stover were chosen as two starting materials that represent
deciduous and agricultural biomass, respectively. Melt compounding was shown to enhance saccharification for both
feedstocks. After melt processing biomass at elevated temperatures, enzymatic digestibility of available glucan for
the extracted substrate reached 90% conversion after 72hrs. The presence of lignin in the sample retarded the rate
in the enzyme-based saccharification, although digestibility for the pretreated fiber without post-extraction or washing
was 80% after 72hrs. Furthermore, lignin was extracted in good yields and had several novel characteristics related
to its molecular weight and structure; the Mark-Houwink-Sakurada exponential constant had a value near that of
randomly coiled polymer in a theta solvent. Hence, melt compounding of biomass offers a route to access the
polysaccharide component within the cell wall and enable the fractionation of lignin that has unique polymer
characteristics for value added applications.
EFFECT OF SURFACTANTS PRE-TREATMENT ON LIGNOCELLULOSIC BIOMASS
Rashmi Kataria1, Luisa Lenzi2 and Ramesh Babu1, 2*
1Centre for Research Adoptive Nanostructures and Nano Devices
2School of Physics Trinity College Dublin, Dublin 2, Ireland
Lignocellulosic biomass has been identified as a high potential feed stock for the biofuel as well as many value added
metabolites production. Several pretreatment methods including chemical, physical, biological and physiochemical at
high severe conditions (high temperature, pressure, and chemical dosage) have been applied on three dimensional
lignocellulosic structure for delignification which is an essential to achieve sufficient saccharification of cellulose in
lignocelluloses. A main concern is the high price of enzyme as well as costly pretreatment process to get high sugar
concentration in economical way. Among all the methods studied, the application of surfactant to lignocellulosic
biomass is a great deal of attention due to its nontoxic nature and economical aspect. Surfactant pretreatment may
reduce the lignin content with liberation of sugars and improves hydrolysis step by reducing the enzyme loading. In
the present study different Surfactants (ionic, non ionic and cationic) including Triton X, Tween 80, SDS, CTAB,
Hexadecyltrimethylammonium p-toluenesolfonate were evaluated for the Rye grass (5% biomass loading)
pretreatment at different temperatures. The liquid residue was analysed for the total reducing sugar estimation and
the maximum sugars liberation with SDS was found to be most effective in term of TRS liberation. Different structural
as well as compositional changes in biomass after pre-treatment were also analysed by using SEM, TGA as well
FTIR. Further, the effect of the surfactant on the hydrolysis step is under progress to achieve the maximum hydrolysis
of sugars. Hence surfactants can be utilized for solubilisation of sugars in pretreatment step and solid residue
remained may be further used for hydrolysis/saccharification in an effective way.
THE BBB PROCESS: BIOMASS TO BIOFUELS AND BIOPRODUCTS MAIN FACTS AND STRUCTURAL FEATURES
Michel Delmas
University of Toulouse, Inp- Ensiacet, 4 allee Emile Monso, 31432 Toulouse cedex 4 - France
CIMV Inc, 134 rue Danton, 92583 Levallois- Perret cedex – France
www.biomass-chemistry.com, www.cimv.fr , [email protected]
The 19thcentury has been the one of coal, the 20th century was the one of oil with a major drawback: the massive
discharge of carbon dioxide in the atmosphere.
Everybody agrees today to say that the 21thcentury will be the one of the biomass if the lignocellulosic part of biomass
found a development at the scale of this annual resource which is worldwide around 7-8 billion tons. It is indeed the
support of the food part of plants as straw for cereals and bagasse for sugar cane, wood residues from forests.
It is thus fatal products of the agriculture without competition with the food sector, available annually in quantities
close to that oil extracted worldwide without changing anything in the current agricultural production. Massive
research investments have been made in USA, Europe and Asia during the last thirty years without real industrial
achievements.
We have solved this worldwide challenge and found how to refine properly the lignocellulosic part of biomass through
a simple separation without degradation of its 3 main components: cellulose, hemicelluloses and lignins: the BBB
process – Biomass to Biofuels and Bioproducts - 12 papers and 8 patents on this clean process are posted on
www.cimv.fr.
I present here the main features of our technology.
Rice, wheat, barley corn straws, sugar cane or sweet sorghum bagasses, hardwoods, switchgrass etc.. are very
suitable with our process for biofuels and bioproducts:
-Cellulose for printing paper and glucose production for bioethanol and bioproducts
-Xylose can be use for biofuels and chemicals like furfurol and derivatives
-Biolignin™ is the flagship product as efficient biofuel or new well defined oligomer for the chemical industry as
phenolic natural polymer base of phenolic resins, glues for particle board, plywood, OSB or carbon black substitutes
in elastomeric compounds.
We have validated the technology at industrial scale with our pilot plant and start the construction of the first industrial
CIMV biorefinery designed to treat wheat, corn or barley straw in 2013.
Figure 1: The conversion of 1,2-propanediol by platinum based catalysts.
THE USE OF PLATINUM ALLOYED BIMETALLIC CATALYSTS TO MANIPULATE PRODUCT DISTRIBUTIONS DURING THE OXIDATION OF POLYOLS
Peter J. Miedziak, Gemma L. Brett, Tatyana Kotionova, Yulia Ryabenkova, David W. Knight, Stuart H. Taylor, Q. He,
C. J. Kiely and Graham J. Hutchings
Cardiff Catalysis Institute Cardiff University
Main Building Park Place
Cardiff Wales
UK CF11 3AT
[email protected] The valorisation of polyols has been the focus of extensive research in recent years, with a large proportion of this work focusing on the oxidation of glycerol, it has been shown that glycerol can be oxidized under mild, green conditions1, 2. These catalysts show similar activity for the oxidation of propane and butane diols. We have shown that by tuning the catalytic parameters such as the choice of alloying metal, support and metal ratio both the conversion and major product selectivity can be enhanced. In certain cases the choice of alloying metal can drive the reaction towards a particular product. These catalysts can be applied to polyol oxidations using water as a solvent. Figure 1 shows the oxidation of 1,2-propanediol in water and shows that tuning the metal ratio can lead to good conversion with simultaneous retention of selectivity to lactic acid, which can be used to form biodegradable polymers. These catalysts from the oxidation of glycerol, 1,2 propanediol and 1,3-propanediol can also be used for the oxidation of various butanediols, these optimized catalyst was active for the oxidation for all the butanediols tested. 1,2-butanediol formed 2-hydroxybutyric acid and 1-hydroxy-2-butanone which are used as flavour and fragrance agents. 2,3 butandiol was selectively oxidised to butandione also used as a flavouring agent. Finally the oxidation of 1,4 butanediol formed butyrolactone as the major product which is used as a chemical intermediate in agrochemicals, pharmaceuticals and dyes. In summary the recent development of platinum based catalysts presents opportunities for increased conversion, reactions under mild conditions and the manipulation of product distribution. The origins of these effects will be discussed. 1. A. Villa, G. M. Veith and L. Prati, Angewandte Chemie International Edition, 2010, 49, 4499-4502. 2. G. L. Brett, Q. He, C. Hammond, P. J. Miedziak, N. Dimitratos, M. Sankar, A. A. Herzing, M. Conte, J. A.
Lopez-Sanchez, C. J. Kiely, D. W. Knight, S. H. Taylor and G. J. Hutchings, Angewandte Chemie International Edition, 2011, 50, 10136-10139.
BIOBASED SURFACTANTS: A USEFUL BIOREFINERY PRODUCT THAT CAN BE PREPARED USING GREEN MANUFACTURING
Doug G. Hayes
University of Tennessee Department of Biosystems Eng & Soil Science
2506 E.J. Chapman Drive Knoxville, TN 37996-4531 USA
Biobased surfactants, readily prepared from common biorefinery process streams and commonly employed as
emulsifiers, wetting agents, plasticizers, and agents for lowering surface and interfacial tension, are becoming
increasingly popular for use in foods, cosmetics, pharmaceuticals, and other industries. This trend is driven by the
increase of cost for petroleum, the enhanced environmental sustainability provided through use of renewable
resources, and the increased abundance of bio–based feedstocks resulting from development of biorefineries.
Although most biobased surfactants are manufactured by chemical means, their preparation via bioprocessing is very
attractive for future employment due to further enhancement of sustainability and potential savings in energy,
downstream purification, and disposal costs. This presentation provides an overview of current research and
development to prepare biobased surfactants via conventional and enzymatic processes, and features work by
the author in preparing sugar ester surfactants using lipases in solvent-free media. Yields of 90-95% have been
achieved using stoichiometric feeds; therefore, minimal downstream purification would be required.
PREPARATION AND CHARACTERIZATION OF MODIFIED LIGNIN FOR THE PRODUCTION OF CARBON FIBERS
Sabornie Chatterjee, Alexander Johs and Orlando Rios
Oak Ridge National Laboratory Oak Ridge, TN 37830, U.S.A.
Lignin, one of the most abundant and cheap natural biopolymers, can be efficiently converted to low cost carbon
fibers. From light weight automobile to energy storage applications, lignin carbon fibers can be used for a wide range
of applications. However, different applications require different types of carbon fibers. The property of lignin fibers
vastly depend on its precursors. Thus, by modifying the precursor, lignin fibers can be customized for a specific
application. In this work, a series of modified lignin samples were prepared from Alcell and softwood lignin and we
developed procedures to modify key functional groups. Further, these procedures were optimized to obtain high
yields of modified precursors at low cost. All lignin samples were characterized by NMR (13C and HMQC) which
clearly showed structural changes in modified lignin samples. Thermo-gravimetric analysis (TGA) and differential
scanning calorimetry (DSC) generally revealed higher thermal stability of modified lignin precursors compared to
unmodified lignin samples. Precursor modification affects parameters for melt processing, stabilization and
carbonization, which impacts the material properties of the final carbon fiber. Our current efforts focus on the
characterization of the lignin carbon fiber microstructure.
REDESIGNING ESCHERICHIA COLI METABOLISM FOR OBLIGATE ANAEROBIC PRODUCTION OF BIOFUELS AND BIOCHEMICALS
Cong T. Trinh
The University of Tennessee
Department of Chemical and Biomolecular Engineering Knoxville, TN 37996
Relevant hosts such as Escherichia coli are commonly engineered and optimized to produce target products
with different genetic modifications. An engineered host that is optimized to produce one target product may not be
suitable to function as a host to efficiently produce other target compounds. To address this bottleneck, we have
applied the metabolic pathway analysis tool based on elementary mode analysis to design an optimal modular cell
that can metabolically couple with a diverse class of chemicals- and biofuels-producing pathways as exchangeable
and tunable modules to efficiently produce a diverse set of chemicals and biofuels at high yields, titers, and
productivities. We will present the design, construction, and characterization of an optimal modular cell that can
couple with different types of exchangeable and tunable modules to produce short-chain length (<C6) alcohols and a
diverse spectrum of their derived esters under anaerobic conditions.
INVESTIGATION OF STRUCTURAL CHANGES IN Cel7A CELLULASE WHEN BOUND TO CELLULOSE SUBSTRATES
Hugh O’Neill1, Junhong He1, Sai Venkatesh Pingali1, Loukas Petridis2, Volker S. Urban1, William T. Heller1, Barbara R. Evans3, Paul Langan1, Jeremy Smith2, and Brian Davison2
1Biology and Soft Matter Division, 2Biosciences Division, 3Chemical Sciences Division,
Oak Ridge National Laboratory 1 Bethel Valley Road
4500N MS 6194 Oak Ridge, TN 37831
Cellulose is the major component of plant cell walls, accounting for almost half of their net weight, and so has the
potential to be a plentiful feedstock for the production of ethanol for biofuels. It is converted to glucose by the enzyme
cocktails secreted by fungi and bacteria. A deeper mechanistic understanding of this saccharification of cellulosic
biomass, which is recognized as a bottleneck in biorefining applications, could enhance the efficiency of biofuel
development. Cellobiohydrolase I (Cel7A) is a major component of the cellulytic enzyme cocktail secreted by the
fungus Trichoderma reesei. We investigated the solution structure of T. reesei Cel7A using small-angle neutron
scattering (SANS) at pH values between pH 4.2 and 7.0, corresponding to a pH range from maximum enzymatic
activity to minimal activity, respectively. SANS showed that the protein is ~100 Å long, and its structure varies subtly
with changes in the pH value of the buffer solution. At the enzyme’s optimal pH of 4.2, the tight packing of the
polypeptide chain in the catalytic core observed at the higher pH values is disrupted without changing the secondary
structure. This suggests that the increased flexibility afforded by such a state is important for function. We have
extended this work to investigate of the structure of Cel7A when bound to cellulose substrates to gain new insight into
the mechanism of action of this protein. SANS is ideally suited for this investigation because it is possible to
distinguish the scattering contributions of different components in a complex mixture using the contrast variation
technique. Approaches for producing deuterated crystalline cellulose substrates were developed to enable these
studies. The techniques employed in this research are broadly applicable to investigating solution structures of
proteins under a wide range of environmental conditions and can provide structural information on complex systems
that is not attainable by other means.
GENETIC ENGINEERING OF STREPTOMYCES BACTERIA AS LIGNOCELLULOSE BIOREFINERIES
Jason K. Sello
Department of Chemistry
Brown University Providence, RI, U.S.
The search for a renewable energy source to act as an alternative to fossil fuel is of global importance. The
use of plant biomass as a source of low-value carbon that can subsequently be used to produce high-value biofuels
has shown great potential. Most attention is focused on the conversion of the cellulose component of plant biomass,
however, this process is impeded by the presence of lignin, a complex aromatic polymer found in the cell walls of
plants. The means to effectively and efficiently degrade lignin would enhance the ability to harness the energy stored
in plant biomass into a usable fuel. Several ligninolytic species of Streptomyces bacteria have been identified,
including S. viridosporus and S. badius. Although it is known that members of the Streptomyces genus are able to
degrade lignin, little is known about the underlying genetics and biochemistry. In collaboration with the Joint Genome
Institute (JGI), the genome of S. viridosporus was recently sequenced. Through this effort, we hope to identify genes
encoding novel peroxidases, laccases, and oxidases. The major utilization pathway for lignin-derived aromatic
compounds in microorganisms is the β-ketoadipate pathway. Through this pathway, the aromatic compounds (i.e.,
protocatechuate and catechol) are converted to acetyl coenzyme A and succinyl coenzyme A. We have found that
transcription of genes encoding enzymes of the protocatechuate branch of the β-ketoadipate pathway are induced by
protocatechuate in Streptomyces coelicolor and Streptomyces viridosporus. In a series of genetic and biochemical
analyses, we have identified the mechanism by which transcription is regulated. In keeping with our larger objective of
converting lignin derived aromatic compounds to biofuels, we have new evidence that S. coelicolor can convert the
carbon of protocatechuate into the triglyceride precursors of biodiesel.
PRODUCING DROP-IN HYDROCARBON BIOFUELS FROM LIGNOCELLULOSIC BIOMASS MATERIALS
Birgitte K. Ahring
Center for Biofuels and Bioproducts Washington State University
2710 Crimson Way Richland, WA 99354
Biofuels from biomass materials in the form of cellulosic bioethanol is now slowly being implemented to substitute the
use of corn as a raw material or for installment of new bioethanol production capacity. While this implementation will
ensure that sufficient capacity is present for meeting the need for a gasoline biofuels additive this production will have
no influence on the needs by for instance the aviation, shipping and defense sector demanding hydrocarbon biofuels
which are similar to the conventional jetfuel and diesel and therefore can be dropped in directly in the current fuel
infrastructure. Drop-in hydrocarbon biofuels can be produced using both thermochemical and biochemical conversion
schemes.
In the presentation we will focus on the biochemical conversion of biomass material which first of all demands a
suitable pretreatment technology for opening the materials and make it suitable for further biochemical conversion
with and without enzymatic hydrolysis. The end-product of the fermentation will often be a platform molecule which
needs further catalytic upgrading for production of the desired final fuel. We will present data from work done in our
laboratory on production of isoprene form cellulosic sugars using Bacillus strains as well as direct conversion of
pretreated materials using filamentous fungi such as Gliocladium species for production of a diesel blend. Finally we
will discuss a new concept, BioChemCat, for production of drop-in hydrocarbon biofuels directly from pretreated
biomass materials using a stable consortium of thermophilic bacteria. This concept is currently under testing in pilot
scale in our laboratory.
CELLULASE PRODUCTION BY SOLID STATE FERMENTATION ON WET CORN DISTILLERS GRAINS
Hossein Noureddini, Hunter R. Flodman
University of Nebraska-Lincoln
Department of Chemical and Biomolecular Engineering 207H Othmer Hall
Lincoln, NE 68588-0643, USA
The effects of temperature and initial moisture content on cellulase production by solid state fermentation (SSF) were
investigated using wet distillers grain (WDG) from a dry grind corn ethanol production process as a substrate. The
CO2 evolution rate was measured to indicate fungal activity of the microorganism used, T. reesei NRRL 11460. The
substrate weight loss and the moisture content were also monitored throughout the fermentation. The highest yield of
cellulase was 28.8±0.8 filter paper units (FPU) per gram of substrate. The effectiveness of the crude enzyme cocktail
was tested by hydrolyzing WDG to monomeric sugars. Approximately 0.44 g of WDG is required to produce a
sufficient quantity of enzymes to hydrolyzed 1 g of WDG. A 100 million gal/yr ethanol production process could
increase production by up to 6.4 million gal/yr if a portion of the WDG was used for cellulase production to hydrolyze
the remaining balance of dilute acid pretreated WDG. Because the monomeric sugar solution from hydrolysis is
relatively dilute compared to sugar concentrations used for corn ethanol production, the hydrolysate would likely be
used as dilution water to produce the slurry for corn ethanol production thereby utilizing existing fermentation and
distillation equipment. The residual spent SSF substrate was investigated as an animal feed product. Significant
reductions in acid detergent fiber (ADF), neutral detergent fiber (NDF), and phytate phosphorus coupled with residual
cellulase enzymes make the fermented WDG an attractive feed for ruminants and nonruminants. Hydrolyzed WDG
was also investigated for feed quality.
EXPLOITING NATURE’S DIVERSITY FOR THE DEVELOPMENT OF CHEMICAL BUILDING BLOCKS
Christian V. Stevens
Department of Sustainable Organic Chemistry and Technology Faculty of Bioscience Engineering
Ghent University Coupure Links 653, 9000 Ghent, Belgium
Renewable resources are getting a lot of attention nowadays since fossil fuel prices are sky high and the reduction of
green house gasses is an important ecological and political issue.
Although most attention goes to bio-energy related issues, the development of bio-based materials and chemical
building blocks will be essential when fossil fuel reserves continue to decrease. Next to some general aspects, the
lecture will focus on three research areas in which our group is active.
The chemical modification of inulin, the reserve polyfructose polymer of chicory, will be described together with the
testing and the commercialisation of the derivatives. Inulin carbamates have been produced as an emulsifier with
excellent activity in high salt applications. The emulsifier is now being used in cosmetics and has potential in the paint
and the polymer industry.
Further, multidisciplinary work on the modification of chitosan will be discussed. Chitosan, the biopolymer prepared
from crustaceae waste, has been chemically modified and their fungicidal and insecticidal properties have been
studied. The modification has been performed by esterification and reductive amination methods. The modified
polymers show promising activity against Spodoptera littoralis as a pest insect and show a 10 fold increased
fungicidal activity compared to unmodified chitosan.
A third domain which will be described deals with the chemistry of castor oil, extracted from the seeds of Ricinus
communis (Euphorbiaceae). Castor oil is rich in triglycerides and is employed directly as crude oil in various industrial
fields (coatings, plastics and fibers, detergents, lubricants and others). Ninety percent of the fatty acid content in
castor oil is ricinoleic acid, a monounsaturated and hydroxylated 18-carbon fatty acid, a quite uncommon natural fatty
acid. Thermal degradation of ricinoleic acid yields undecylenic acid, an interesting renewable building block for
organic synthesis. Being interested in discovering green routes to chemicals with a high added value and
intermediates for the pharmaceutical industry, our research group has carried out a facile coupling process of
undecylenic acid, leading to a twenty-two carbon atom acyloin. The study of its reactivity and its applications is
ungoing. Several interesting activities will be presented.
CONVERSION OF CELLULOSIC BIOMASS FROM GRASS INTO FERMENTABLE SUGARS AND ITS EFFECTIVE UTILIZATION FOR BIOSYNTHESIS OF MEDIUM CHAIN LENGTH POLYHYDROXYALKANOATES
(MCL-PHA) BY PSEUDOMONAS SPP
Reeta Davis1, Rashmi Kataria2, Federico Cerrone1, Gearoid Duane3, Eoin Casey3, Ramesh Padamati2, Kevin O’Connor1
1School of Biomolecular and Biomedical Science, and Technology Centre for Biorefining and Bioenergy, University
College Dublin, Belfield, Dublin4, Ireland 2Materials Ireland, Polymer Research Centre, School of Physics, Trinity College Dublin, Dublin2, Ireland
3 School of Biochemical and Bioprocessing Engineering, University College Dublin, Belfield, Dublin4, Ireland
The cost of polyhydroxyalkanoates (PHA) production is invariably dependent on the carbon source used. Sugars
derived from cellulosic biomass offer promising low cost feedstock for bacterial growth and bioplastic production.
Plant biomass, such as grass, is a sustainable source of energy which consists of mainly cellulose and
hemicelluloses. In this study, cellulose generated from biomass using different pretreatment methods followed by
enzymatic treatment with commercial cellulase cocktails were compared for efficient conversion into fermentable
sugars. Differentially treated cellulose at 4-7% substrate loading after 24-48h resulted in 71-95% conversion into
fermentable sugars. HPLC analyses of the hydrolysates showed it to contain 75-80% glucose with the remainder
composed of xylose, arabinose, galactose, and mannose. We report here on the ability of various PHA accumulating
strains to utilize these sugars for growth and PHA production. A comparison of growth and PHA productivity from
commercially available glucose and cellulose hydrolysate revealed no significant difference in cell dry weight (CDW)
and PHA composition. PHA accumulated from the cellulose hydrolysate was similar for all strains tested with 60-70
mol% of (R)-3 hydroxydecanoic acid monomer. HPLC analyses of the culture supernatant revealed preferential
utilization of hexoses over pentose sugars by these bacterial strains.
Fig. 1 Enzymatic hydrolyses of differentially treated biomass into fermentable sugars. % conversion was calculated
by estimating the sugars released at different time interval by Dinitrosalicylic acid method. Treatment A and treatment
B correspond to different chemical treatment applied to the grass biomass prior to enzyme hydrolyses.
SURFACE AND SUBSURFACE PHYSICAL AND CHEMICAL CHARACTERIZATION OF MATERIALS AT THE NANOSCALE
Laurene Tetard
Oak Ridge National Laboratory
Oak Ridge, TN
In modern microscopy, spatial and spectral resolutions are of great importance in tackling questions related to
material properties. The emergence of the atomic force microscopy (AFM), which surpasses what can be achieved
optically due to the inherent diffraction limit, has opened numerous opportunities for investigating surfaces. However,
a contemporary challenge in nanoscience is the non-destructive characterization of materials. In addition, techniques
providing both physical and chemical information are needed to reach a comprehensive understanding of the
composition and behavior of complex systems.
In order to tackle the subsurface and spectral imaging, here we propose to make use of the nonlinear interaction
forces between the atoms of an AFM probe tip and those of a given sample surface. Such forces are known to
contain a short range repulsive component and a long range van der Waals attractive contribution. This interfacial
force can give rise to a multiple-order nanomechanical coupling between the probe and the sample, offering
tremendous potential for obtaining a host of material characteristics. By applying a multi-harmonic mechanical forcing
to the probe and another multi-harmonic forcing to the sample, we obtain, via frequency mixing a series of new
operational modes. By varying the nature of the excitations, using elastic or photonic coupling, it is possible to obtain
physical and chemical signature of a heterogeneous medium with nanoscale resolution. The technique, termed mode
synthesizing atomic force microscopy (MSAFM) is therefore described as a generalized multifrequency AFM.
We highlight the versatility of MSAFM and its potential to contribute to important problems in material sciences,
toxicology and energy research, by presenting three specific studies: 1- imaging buried nanofabricated structures; 2-
investigating the presence and distribution of embedded nanoparticles in a cell; and 3- characterizing the complex
structures of plant cells.
ENABLING ROBUST PRODUCTION OF BIORENEWABLE FUELS AND CHEMICALS FROM BIOMASS
Laura R. Jarboe*, Liam Royce, Ping Liu, Tao Jin
Department of Chemical and Biological Engineering Iowa State University 3051 Sweeney Hall
Ames, IA 50011
Overcoming biocatalyst inhibition, whether by the target metabolic product, the substrate of interest, or contaminants
in the feedstock, is a significant challenge for cost-effective production of biorenewable fuels and chemicals from
lignocellulosic biomass. Rational engineering efforts can be employed when the mechanism of inhibition is known,
where omics analysis can be used to identify the mechanism. Contrastingly, reverse engineering of evolved strains
can also reveal the mechanism of inhibition. This talk describes examples of both approaches involving production of
inhibitory products, such as short-chain carboxylic acids, and the use of cheap (“dirty”) biomass-derived substrates,
such as pyrolytic sugars and furfural-contaminated biomass hydrolysate.
TANDEM MASS SPECTROMETRY IN THE CHARACTERIZATION OF CONVERTED BIOMASS
Hilkka I. Kenttämaa
Department of Chemistry Purdue University
West Lafayette, IN, USA
Tandem mass spectrometry has been proven to be an invaluable tool in the field of complex mixture analysis and the
identification of unknown molecules directly in mixtures due to its high sensitivity, selectivity, versatility and speed.
This presentation focuses on the development of ionization techniques, novel instrumentation, HPLC methods and
tandem mass spectrometric methodologies for the identification of unknown compounds in complex mixtures
generated by conversion of lignocellulosic biomass. For example, characterization of catalytically converted lignin is
best carried out by using high performance liquid chromatography (HPLC)/multiple stage high-resolution tandem
mass spectrometry using hydroxide-doped electrospray ionization. Eleven model compounds were used to identify
the optimal elution gradient and stationary phase for HPLC separation. Electrospray ionization (ESI) doped with
hydroxide ions allows the ionization of all model compounds without fragmentation. Elemental compositions of the
deprotonated analytes can be determined by high-resolution analysis in the Fourier-transform ion cyclotron resonance
part of the tandem mass spectrometer used. Detailed structural information for the analytes is obtained by multi-stage
tandem mass spectrometry (MSn) experiments on the deprotonated analytes in the linear quadrupole ion trap part of
the instrument. In addition to the acquisition of full mass spectra for the ionized compounds eluting from HPLC (MS1),
fragment ions formed from these ions, and those formed from their fragment ions, and so on, were subjected to
consecutive isolation and collision-activated dissociation (CAD) experiments until no further fragmentation products
were observed. This approach provided valuable structural information for the components of real lignin degradation
product mixtures. Further, tandem mass spectrometry experiments that combine CAD and ion-molecule reactions
often give much more valuable structural information than each individual experiment by itself. These two reaction
processes should be performed in separate and clean environments as their efficiency and information value is
otherwise compromised. Unfortunately, commercial instruments allow these experiments to be performed only up to
MS3. Hence, a new tandem mass spectrometer was built by combining two commercial linear quadrupole ion trap
(LQIT) mass spectrometers with differentially pumped ion trap vacuum chambers. This instrument allows many
stages of clean tandem mass spectrometry experiments involving both CAD and ion-molecule reactions. The utility of
this approach is demonstrated using several examples.
APPLICATIONS OF COMPUTATIONAL CHEMISTRY TO THE REACTIONS OF LIGNIN
Thomas Elder
USDA-Forest Service, Southern Research Station 2500 Shreveport Highway
Pineville, LA, USA
Recent political and economic issues concerning petroleum supply and availability have renewed interest in the use
of biomass as a secure source from which fuels and bioproducts can be developed. While not without difficulties, the
carbohydrate constituents are at least somewhat amenable to chemical processing. The lignin fraction however, with
its variety of interunit linkages, can be more intransigent in this regard. Both chemical and physical methods are
currently being applied to the lignin polymer as routes to useful products. Given the capabilities of computer
hardware and software in addressing structures of the size and complexity of lignin models, this paper is concerned
with the use of contemporary computational methods to aid in interpreting and guiding experimental results. Results
are reported on catalytic oxidation of lignin models and thermochemical reactions.
OVERCOMING RECALCITRANCE OF BIOBASED FEEDSTOCKS THROUGH CATALYTIC CONVERSIONS
Gnana Gnanakaran
Los Alamos
The challenges faced by the lignocellulose-to-ethanol conversion technologies are critically linked to the uncertainties
of the physical properties of the feedstock. During the course of evolution, plant cell walls have become recalcitrant
through architecture and design of its components to deal with environmental stress and pathogen attack. We
present the results of extensive theoretical studies on lignocellulosic biomass that seek to obtain a molecular level
understanding of recalcitrant properties of the cell wall components. Our studies probe these properties using
computational techniques at different levels of resolutions comprising quantum chemical calculations, all atom and
coarse-grained molecular dynamics simulations, polymer and statistical mechanical models and agent based and
traditional kinetic models. We will discuss how such a multi-scale approach can give a coherent view of the molecular
details of the biomass degradation problem.
LIGNIN MODEL PYROLYSIS: A COMPUTATIONAL APPROACH
Ariana Beste and A.C. Buchanan
1Joint Institute for Computational Sciences; University of Tennessee, Knoxville, TN 2Chemical Sciences; Oak Ridge National Laboratory, Oak Ridge, TN
A great amount of insight can be obtained by the computational study of the thermal decomposition of β-O-4 model
compounds, representing the most common linkage in lignin. While experimental work determines overall product
distributions and total rates of reaction, kinetic parameters of individual reactions and details of substituent effects on
equilibrium and transition state structures are difficult to obtain experimentally. Computational methods allow the
location of transition states and the calculation of activation barriers and entropical pre-factors for targeted chemical
reactions. We launched a systematic computational study of the kinetic details of the pyrolysis of phenethyl phenyl
ether (PPE) and various oxygen substituted derivatives, which are model compounds for the β-O-4 linkage in lignin.
Using density functional methods, we investigate relevant reaction steps including homolytic cleavage, competitive
hydrogen abstraction, radical rearrangement, and β-scission reactions.
Electronic structure analysis of reactants, intermediates, products, and transition states is used to explain the effect of
naturally occurring substituents, which can perturb multiple steps of the pyrolysis mechanism. We calculate relative
rate constants using transition state theory, apply analytic kinetic models and kinetic Monte Carlo techniques to obtain
experimentally observed product selectivities and monitor reaction progress as a function of time.
This research was sponsored by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic
Energy Sciences, U.S. Department of Energy and was performed in part using the resources of the Center for
Computational Sciences at Oak Ridge National Laboratory under contract DE-AC05-00OR22725.
FROM PAPER TRAILS TO ELECTRONIC MANAGEMENT SYSTEMS: GREEN LINING THE BIOMASS
CONVERSION PROCESS
Anis H. Khimani, Megean Schoenberg, John Nobles, Joshua Deihl, Peter Muller
PerkinElmer, Inc. 100 CambridgePark Drive
Cambridge, MA 02140
[email protected] The ability to enhance the efficiency of biomass conversion to biofuel for greener alternatives has significant potential
in a rapidly growing alternate energy sector. The optimization of the biomass processing workflows has been an
evolving process where the establishment of informatics architecture can play an important role in streamlining the
steps and enabling collaboration between development, bioprocess/bioconversion, and analytical testing functions.
The presentation will focus on the need for integration and the adoption of informatics capabilities to facilitate
seamless knowledge and process management.
LIGNIN RICH RESIDUES FROM BIOMASS TO CHEMICALS AND FUELS
Guliz Elliott, Aaron Murray, Steve Ryba
Chemtex International, Inc.
6951 Ridge Road Sharon Center, Ohio 44274
Chemtex is completing the construction of a 20MM gallon per year bioethanol plant in Crescentino, Italy utilizing the
PROESA™ technology developed by Chemtex Italia. The PROESA™ process is both a well-developed and simple process that economically produces bioethanol and lignin-rich residues (LRR). PROESA™ has been demonstrated
on a variety of perennial grasses and hardwood feedstocks, and can directly reduce capital costs, increase ethanol
yield, and allow for the utilization of a series of low-cost feedstocks. Currently LRR is used for cogeneration for the
plant. However it can be used as a feedstock for production of higher value chemicals and fuels.
With PROESA™ as the base technology, Chemtex is developing complementary technologies for the conversion of
LRR to value-added hydrocarbons. A deoxygenation process for production of value-added hydrocarbons is
undergoing development in the Chemtex pilot plant in Sharon Center, Ohio.
The usual routes for lignin conversion into chemically attractive products are gasification and reforming or pyrolysis
and refining, both of which have issues. The Chemtex process uses LRR from lignocellulosic ethanol plant, but at
the same time is flexible enough to use lignin-containing raw materials from other processes. The raw materials used
in our technology are derived from naturally occurring lignocellulosic biomass, after the majority of the carbohydrate
fraction has been biologically converted to ethanol. These include LRR from various crop residues (wheat and rice
straw) and dedicated energy crops such as Arundo donax. The sulfur content of our feedstock is very low, and
consequently no desulfurization is required to obtain hydrocarbon fuels (as opposed to a fossil fuel).
In our technology center in Ohio we have gone from batch laboratory scale reactions to continuous laboratory scale
and then to continuous pilot scale process. So far Chemtex has converted various LRR from PROESA™ process
into hydrocarbons highly rich in aromatics both in laboratory scale and pilot scale equipment.
SOLVENT-BASED CATALYTIC STRATEGIES FOR THE SELECTIVE HYDROGENOLYSIS OF LIGNIN AND SELECTIVE DEFUNCTIONALIZATION OF BIO-OIL UNDER LOW-SEVERITY CONDITIONS
Roberto Rinaldi,* Xingyu Wang
Max-Planck-Institut für Kohlenforschung
Kaiser-Wilhelm-Platz 1 D-45470 – Mülheim an der Ruhr, Germany
The conversion of lignin, the most recalcitrant of the biopolymers, is required for a carbon-efficient processing of
lignocellulosic materials. In this context, hydrogenolysis of lignin is a process option receiving currently increasing
attention. In the first part of this communication, the solvent effects on the performance of Raney Ni in the
hydrogenolysis of diphenyl ether will be addressed.1 The practical implications for the hydrogenolysis of lignin will be
also discussed. GC×GC-MS reveals that conducting the hydrogenolysis of lignin in methylcyclohexane results mainly
in saturated products (e.g., cyclic alcohols and cyclic alkanes), whereas performing the reaction in 2-propanol leads to
a very complex mixture of saturated and unsaturated products (e.g., cyclic alcohols, cyclic ketones and
hydrocarbons). In turn, when carried out in methanol, the hydrogenolysis of lignin leads to phenols.
In the second part of this communication, the fundamental chemical aspects of hydrogen transfer reactions with
Raney Ni and 2-propanol in the defunctionalization and hydrodeoxygenation of phenolic and aromatic biorefinery
feeds under low-severity conditions will be addressed.2 A series of 32 model substrates were explored, providing a
comprehensive description of the reactivity of Raney Ni toward transfer hydrogenation and transfer hydrogenolysis of
phenolic and aromatic compounds. With regard to the processing of a model-substrate mixture, important features of
the chemoselectivity of Raney Ni were also revealed. Hydrogen transfer reactions could hold the key for the upgrade
of bio-oil under unusual, low-severity conditions. In fact, bio-oil was easily upgraded to cyclohexanols and less
functionalized alkylphenols, with Raney Ni and 2-propanol, already at 120 °C. Full saturation of bio-oil to cyclic
alcohols, cyclohexane-1,2-diols and other products with reduced oxygen content was achieved at 160 °C under
autogenous pressure.
REFERENCES
1. X. Wang, R. Rinaldi, Solvent effects on the hydrogenolysis of diphenyl ether with Raney Nickel and their
implications for the conversion of lignin,ChemSusChem 5 (2012) 1455-1466.
2. X. Wang, R. Rinaldi, Exploiting H-transfer reactions with Raney Ni for upgrade of phenolic and aromatic
biorefinery feeds under unusual, low-severity conditions. Energy & Environmental Science, 5 (2012) 8244-8260.
HIGH THROUGHPUT BIOMASS CONVERSION IN SUPERCRITICAL WATER AND PRODUCT SEPARATIONS AS AN “END OF PIPE” TECHNOLOGY IN A BIOMASS REFINERY
Doug Hendry, Nikolas Wilkinson, Malithi Wickramathilaka, Andrew Miller, Reza Espanani, and William Jacoby
Biological and Chemical Engineering Departments, University of Missouri
236 Agricultural Engineering Building University of Missouri Columbia, MO 65201
At Mizzou’s Carbon Recycling Center (CRC), we believe that supercritical water gasification (SCWG) has great
potential as “end-of-pipe” technology for producing high-pressure, high-value fuel gas from wet solids including
biomass and other carbonaceous residues. We take a non-catalytic approach as we believe catalysts complicate
operation and have shown that catalysts are not necessary for full conversion during SCWG. We have demonstrated
the broad utility of this approach using our batch reactor and documented unprecedented reaction rates using our
continuous reactor. We have observed full conversion of a variety of feed materials including algae, coal, biomass
wastes (rice straw, corn cob, and others) as well as several model compounds to go along with gasification rates that
are an order of magnitude higher than reported in other SCWG studies. Along with promising results with high
throughput conversion, we will present some of the advances in upstream and downstream processing of SCWG that
have been made on our continuous SCWG apparatus. These advances bring supercritical fluid technologies closer
towards commercialization.
Two of the largest engineering challenges encountered in a biorefinery are: 1) feeding and 2) separations. To
address problems with feeding (upstream processing), we have developed a novel feeder capable of precisely
delivering a large variety of solid slurries into high-pressure (and high-temperature) environments using fluid power.
At the CRC, we use the feeder for continuous SCWG, but the feeder has applications in other supercritical fluid
technologies. The feeder has proved capable of feeding slurries over 50% solids (thick pastes) against pressures of
over 45 MPa. This feeder is currently used on a laboratory scale, but is amenable to scale up.
Novel work in downstream processing (i.e. separations) during SCWG will also be presented. The main products of
SCWG are H2, CH4, and CO2. We have shown that this product mixture forms an equilibrium separation at
temperatures at or below ambient and pressures above 20 MPa. Experiments were done in an isolated high pressure
equilibrium phase separator. Dense phase CO2 can be removed from the bottom of the separator and light phase H2
and/or CH4 can be removed from the top. In this way, CO2 is removed during ‘carbon capture’ leaving a valuable
mixture of H2 and CH4. Increases in pressure and decreases in temperature increased the separation efficiency. We
will soon attempt to demonstrate this equilibrium separation in our continuous SCWG apparatus.
CONVERSION OF SUGARS TO HYDROCARBONS VIA DEPOLYMERIZATION AND DECARBOXYLATION OF POLYHYDROXYALKANOATES
David K. Johnson, Luc Moens, Ashutosh Mittal, Heidi M. Pilath, Todd B. Vinzant, Wei Wang,
and Michael E. Himmel
Biosciences Center and National Bioenergy Center National Renewable Energy Laboratory
1617 Cole Blvd., Golden, CO 80401
There are many potential chemical intermediates that can be made by fermentation of sugars, and a variety of
chemicals that could be made by growing organisms such as fungi on biomass. Virtually all of these intermediates
require some form of chemical transformation before they are ready to be used as infrastructure-compatible (drop-in)
transportation fuels. Based on a survey of the potential products that can be made from biomass components by
chemical and biological routes and the feasibility of transforming them into hydrocarbon fuels it is obvious that there
are two main transformations that need to occur, deoxygenation and carbon chain extension. The potential routes for
decreasing the oxygen content of biomass intermediates include dehydration, hydrodeoxygenation and
decarboxylation. We are developing chemical transformation routes to efficiently convert biomass-derived
intermediates into fuel products that are compatible with the existing fuel distribution infrastructure, which fit within the
specifications for gasoline, jet or diesel fuels.
A potential route that is being examined is the conversion of polyhydroxyalkanoates (PHA) to alkenes that would be
intermediates to hydrocarbon fuels. This route appears promising as there are several microorganisms, which
incorporate high levels of PHA (up to 80% of dry cell mass) as a form of energy storage molecule to be metabolized
when other energy sources are not available. Thermal breakdown of PHA proceeds via an intermediate carboxylic
acid, which can then be decarboxylated to an alkene. Oligomerization of alkenes by well known commercial
technologies would permit production of a range of hydrocarbon fuels from sugar intermediates.
Polyhydroxybutyrate (PHB) can be produced in Cupriavidus necator (formerly known as Ralstonia eutropha) on a
variety of carbon sources including glucose, fructose and glycerol with PHB accumulation reaching 75% of dry cell
mass. We have demonstrated the thermal breakdown of polyhydroxybutyrate to 2-butenoic acid (crotonic acid, CA)
and demonstrated thermal decarboxylation of CA to propene at yields approaching 70% at 400oC in 15 min.
Combining the breakdown and decarboxylation steps we have demonstrated that PHB can be directly converted to
propene and carbon dioxide under similar conditions and in similar yields. PHB containing cell mass from
Cupriavidus necator has also been directly converted to propene and carbon dioxide without prior separation of PHB
from the cell mass. Current research is aimed at finding catalysts that would permit lower temperature
decarboxylation and higher propene yields.
CARBON FIBER FROM ENGINEERED LIGNINS
Darren A. Baker
Center for Renewable Carbon, University of Tennessee 2506 Jacob Dr.
Knoxville, TN, 37996, USA
Lignin has received much recent interest towards the manufacture of value-added chemicals, fuels and materials. The
focus on materials has been in the manufacture of value added products to enhance the economics of the existing
pulp and emerging biorefinery industries. Most lignin product research has been directed towards the use of
commercial lignins in the manufacture of carbon fiber, and also in resins where the lignin is added as a replacement
for one of the active components or as a low cost extender. Particular barriers to the utilization of lignin in value added
products have been caused mainly by inorganic and polysaccharide impurities and also the polydispersity of the
particular lignins used.
The Center for Renewable Carbon (CRC) has embarked on a program to manufacture lignin products from both
biomass and commercial lignins and has several areas of interest, which include the manufacture of carbon fiber,
carbon nanofibers, lignin polymer fiber, carbon foams, graphitic materials and carbon-carbon composites. The
products are expected to find applications in markets that utilize structural, insulating, conductive, separation, energy
storage, filtration and light-weighting materials.
The manufacture of carbon fiber is a complex process, and is especially so with the use of lignin as precursor, since
the purity and properties of various lignins are diverse. The presentation will describe work performed at CRC towards
the manufacture of low-cost carbon fiber from lignin. A brief review of prior lignin carbon fiber work, carbon fiber
processing and economics will be given, followed by presentation of earlier data gathered from work previously done
using thermally engineered lignins by the presenter. More recent work on the purification and successive solvent
extraction of technical kraft and organosolv lignins, and also the manufacture of high purity lignins using a CRC
organosolv process will then be presented.
PYROLYSIS OF LIGNIN TO CREATE A NEW FOUNDRY FUEL SOURCE
Nicole R. Brown, Curtis Frantz, Matthew S. Lumadue, Fred S. Cannon, Sridhar Komarneni
The Pennsylvania State University 226 Agricultural and Biological Engineering
University Park, Pennsylvania, USA
Traditionally, coke has been the standard cupola foundry fuel source. Coke consists of a very strong and porous
matrix containing a low amount of volatile chemicals. The coking process consumes about 20% of the energy
efficiency of the fuel, and is a highly polluting process. We have produced a coke substitute made from industrial
wastes including anthracite fines (a stockpiled residue) and lignin. The “briquette” produced has the necessary
porosity and mechanically withstands the extreme conditions of the cupola furnace, acting as a suitable substitute for
coke.
In this presentation, chemical characterization of the briquettes will be discussed, primarily relating to the evolution of
lignin chemistry under high temperature pyrolyzing conditions. GC-MS and 13C CP-MAS NMR spectroscopy show the
rapid disappearance of oxygen-containing functionalities and the transformation from ambient lignin to a fused poly-
aromatic structure. Homolysis of the C-O bonds between the methoxyl oxygen atoms and the aromatic carbon at
approximately 400°C serves as the initiation of this conversion. This homolysis likely leads to radical coupling, and
eventually the formation of the polyaromatic char. The strength of the briquettes will also be discussed.
CHEAP AND ABUNDANT CATALYSTS FOR BIOMASS CONVERSION INCLUDING LIGNIN
Mahdi M. Abu-Omar, Eurick Kim, Trenton Parsell, Christine Bohn, Ian Klein, and Nathan Mosier
Purdue University The Center for direct Catalytic Conversion of Biomass to Biofuels
Department of Chemistry, and School of Agriculture and Biological Engineering West Lafayette, Indiana 47907, USA
Biomass is a renewable source that can be used for the production of liquid fuels and valuable chemicals.
Development of chemical catalysis for the fractionation of sugar and lignin components of biomass and their
subsequent conversion has attracted intense attention over the past few years. The use of organic acids enables
solubilization of the hemicellulose fraction of the biomass and dehydration of xylose to furfural. We discovered the
combination of organic acids with Lewis acids such as aluminum enables the extraction of both C-5 (hemicellulose)
and C-6 (cellulose) sugars and their dehydration to furfural and hydroxymethylfurfural, respectively. Cheap and
abundant transition metals have also been used successfully to obtain levulinic acid and H2 directly from biomass
variants. We will report on examples with corn stover, switch grass, poplar, and pinewood. Even though lignin is a
minor component of the total biomass, it represents a significant portion of the energy content. A robust and
recyclable catalyst system based on palladium and zinc has been developed in our laboratory for the cleavage of
ether bonds that are prevalent in lignin. The same catalyst can also affect the hydrodeoxygenation (HDO) of the
resulting monomeric units of lignin to substituted phenols. Application of this new catalytic technology to engineered
biomass will be briefly described.
NEW TECHNOLOGIES FOR WOOD PRETREATMENT WITHIN THE CONCEPT OF THE BIOREFINERY AND NOVEL USES OF CELL WALL COMPONENTS
Orlando J. Rojas
1North Carolina State University
Departments of Forest Biomaterials and Chemical and Biomolecular Engineering Campus Box 8005 Raleigh, NC 27695
This work addresses a novel technology for biomass pre-treatment by using aqueous-based microemulsions that are
able to effectively penetrate the complex capillary structure of wood. Such concept has been recently discussed as
far as the enhancement of flooding or fluid penetration as well as the dissolution of some of the components of the
fiber cell wall (JCIS 381, 171–179, 2012). In this talk we will unveil the role of emulsion formulation and composition in
the extent of impregnation of different wood species. We will show that salinity and the concentration of the minor, oil
phase critically affects the process. In addition, surfactant choice and the synergies of surfactants mixtures play an
important role as far as the extent and dynamics of fluid penetration. This is explained by the affinity between the
surfactant(s) and the solid which contains conductive elements with different biomolecular constituents. With the
appropriate surfactant mixture it was possible to enhance the penetration of the microemulsions (atmospheric
pressure and temperature) in white pine by 83%, compared to water. We fill end the discussion by introducing some
possibilities we have explored in our group as far as the industrial utilization of lignin, for example in fibers and as
stabilizer of crude oils for fuel emulsions and cellulose for the production of nanopaper from waste streams.
BIOSYNTHESIS AND CHARACTERIZATION OF MEDIUM-CHAIN-LENGTH POLY (3-HYDROXYALKANOATE)S
Hideki Abe1,2, Naoki Ishii2, and Takeharu Tsuge2
1 Bioplastic Research Team
RIKEN Biomass Engineering Program Hirosawa 2-1, Wako, Saitama 351-0198, Japan
Department of Innovative and Engineered Materials 2 Tokyo Institute of Technology
Nagatsuta 4259, Midori-ku, Yokohama 226-8502
Polyhydroxyalkanaotes (PHAs) are biodegradable polyesters produced by bacteria and are recognized as candidate
materials for sustainable development. Based on the structure of monomeric units, PHAs are divided into two groups;
short-chain-length (scl) PHAs consisting of hydroxyalkanoate units with 3 to 5 carbon atoms, and medium-chain-
length (mcl) PHAs containing hydroxyalkanoate with over 6 carbon atoms. In this study, we synthesized the medium-
chain-length poly(3-hydroxyalkanoate)s (mcl-P(3HA)s) with different side-chain-length ranging from C3 to C9 carbon
atoms and characterized the physical properties and solid-state nano-structure of mcl-P(3HA)s. In addition, the
thermal degradation behaviors of mcl-P(3HA)s were examined to focus on 2-alkenoic acids as a recyclable carbon
source. Mcl-P(3HA)s with different side-chain length ranging from C3–C9 were synthesized from 2-alkenoic acids of
C6–C12 by using a recombinant Escherichia coli. All mcl-P(3HA)s formed a chain-packed crystalline structure in the
solvent-cast films. Melting temperatures of solvent-cast film of mcl-P(3HA)s first decreased from 59 °C to 45 °C with
the change of side-chain from C3 to C4 and thereafter increased to 69 °C with an extension of side-chain to C9. The
X-ray diffraction patterns indicate the formation of a layered structure aligned the main-chains in planes involving
side-by-side packing of side-chains with a periodic distance of 1.6–2.8 nm for the mcl-P(3HA)s with over C4 side-
chain. The interlayer distance increased proportionally to the length of side-chain for the mcl-P(3HA)s with over C4
side-chain, while the corresponding value of mcl-P(3HA) with C3 side-chain was apparently deviated from the
extrapolated line plotted the distance against side-chain length. These results indicate that the changeover in
crystallization manner occurs between P(3HA)s with under C3 side-chain and with over C4 side-chain. For the mcl-
P(3HA)s with side-chain carbon number over C7, two distinct phase transitions were happened during heating
process from a melt-quenched amorphous state. At lower temperature region, the mcl-P(3HA) molecules formed a
smectic liquid-crystalline structure owing to the side-chain interactions, and the structure was disrupted at
temperatures between 20–50 °C. After the disruption of smectic aggregates, the crystallization of mcl-P(3HA) chains
immediately occurred with participation of both main- and side-chains. The finding of phase transition from liquid-
crystalline to crystalline state promises to use them as thermo-responsive biomaterials. The pyrolysis products of
mcl-P(3HA)s were dominantly 2- alkenoic acids used as a carbon source for the mcl-P(3HA) biosynthesis. This result
demonstrates the feasibility of PHA recycling via 2-alkenoic acids, which act as pyrolysis products and raw materials
for PHA biosynthesis.
PRODUCTION OF HIGH-VALUED CHEMICALS FROM FRACTIONAL CATALYTIC PYROLYSIS OF BIOMASS
Foster A Agblevor and O. Mante*
Biological Engineering Department Utah State University, Logan UT *Brookhaven National Laboratory
Upton, NY The production of high-valued chemicals from biomass feedstocks is a very important complementary activity that can
make biofuels production economically viable and competitive with fossil derived fuels. Pyrolysis technology can
convert biomass feedstocks into a complex mixture of oxygenated compounds and a small fraction of hydrocarbons
depending on the feedstock and pyrolysis conditions. Traditional petrochemical separation methods do not yield
useful results because the pyrolysis oils are too reactive and tend to form solids and so prevents useful separations.
We have developed the fractional catalytic pyrolysis (FCP) method that uses catalysts to target specific
decomposition products of the biomass during pyrolysis and converts them to a defined fraction of compounds. The
oils are more stable and the pH is relatively high compared to conventional pyrolysis liquids. In the production of
phenol-rich liquids, we used catalysts that targeted carbohydrate decomposition products and selectively gasified
these components into C1 to C4 compounds and thus enriching the pyrolysis liquids in phenols. The phenols
produced can be used for applications such as non-formaldehyde resins, phenol/formaldehyde resins, epoxidized
novolacs and other products. We have also demonstrated that by judiciously selecting suitable catalysts, we can
selectively convert the lignin fraction of the pyrolysis oils into gases and obtain anhydrosugar-rich liquids that can be
used for various applications. Liquids generated using the fractional catalytic pyrolysis process require minimal post
pyrolysis separation and can be used as is. Thus we have successfully substituted 95% of phenol with FCP oil in the
preparation of phenol/formaldehyde resins and we have used the anhydrosugars-rich liquid to prepare biobased
polyurethane foams.
ENGINEERING BACTERIA TO PRODUCE BIO-STYRENE AND OTHER AROMATIC CHEMICALS
David R. Nielsen, Rebekah McKenna, Shawn Pugh, Matthew Sawtelle, Warinsinee Phusitkanchana
Chemical Engineering, Arizona State University
ECG 301, 501 E. Tyler Mall Tempe, AZ, 85281, USA
Aromatic compounds represent a diverse class of fine and commodity chemicals with important commercial
applications ranging from their use as molecular building blocks, flavor agents, and monomers. Today, conventional
chemocatalytic synthesis routes for all aromatic compounds rely upon petroleum-derived BTEX (benzene, toluene,
ethylbenzene, and xylenes) compounds as feedstock. However, through de novo pathway engineering, our lab has
been exploring the ‘bottom up’ development of microbial biocatalysts to produce a number of useful aromatics from
renewable feedstocks.
Styrene, for example, is an important commodity chemical with versatile commercial applications, predominantly as a
monomer building block for the production of many useful plastics. Today, all styrene is produced via chemocatalytic
routes from petroleum-derived benzene or ethylbenzene according to an energy intensive process. Recently, our
group engineered a non-natural enzyme pathway to instead produce styrene from renewable feedstocks. By over-
expressing both PAL2 from Arabidopsis thaliana and FDC1 from Saccharomyces cerevisiae in a phenylalanine over-
producing Escherichia coli host we have engineered the first styrene-producing microbe. Initial shake flask cultures
have produced ~300 mg/L styrene, which approaches the determined toxicity threshold. Subsequent works have
since sought to overcome several of critical limitations of this preliminary work. Here we present our progress in this
regard on several fronts, including by developing strategies to increase pathway flux, overcome product toxicity, and
by exploring alternative substrate feedstocks.
Building upon this theme, we have also begun applying the same pathway engineering strategies and principles to
engineer bacteria to produce other, additional aromatic chemicals from renewable sugars. One such example is the
chiral building block (S)-styrene oxide whose conventional applications include its use as a reactive plasticizer and as
a chemical intermediate for cosmetics, surface coatings, and agricultural and biological chemicals. Our current titers
here already approach the toxic threshold of (S)-styrene oxide, determined as ~1.6 g/L. In more recent applications
we have also developed pathways for useful aromatic acids and alcohols. This presentation will provide an overview
and summary of our past and current research related to this area.
ADVANCED PURIFICATION TECHNOLOGIES FOR YOUR BIO-BASED CHEMICALS
John Bhatt, Frederic Schab, Thibault Lesaffre
NOVASEP
23 Creek Circle Boothwyn, PA 19061
Biomass can be converted into a very broad range of products. Traditionally, parts of the plant were used as animal
feed, as source of carbohydrates for human nutrition, etc. A new usage is currently being developed: producing
industrial chemicals using the whole plant: bio-based chemicals. Targeted molecules are main intermediates of the
petro-based chemistry, also named “platform molecules” or “building blocks”, such as 1,3 PDO or succinic acid.
To enter the chemical value chain, and to allow direct substitution as drop-in chemicals, bio-based building blocks
must fit with current specifications applied to petro-based chemicals. Purity is therefore an essential quality parameter
of bio-based chemicals.
Biomass is made of cellulose, hemicellulose and lignin, but it is extremely diverse: biomass is a generic term covering
a huge number of species, with a huge variety of compositions. Cellulose / Hemicellulose ratio may vary;
hemicelluloses can be made of C5 or C6 sugars, lignin can be made of different sizes of polymers, etc.
So the main challenge facing bio-based chemicals producers is: how to transform in a cost-effective manner such a
diverse raw material made of complex molecules, into a standardized, pure biochemical?
Novasep’s advanced purification technologies can help to fill this gap !
Novasep is specialist in solving purification challenges, from process development to industrial installations, and from
laboratory equipment to turnkey plants. For this, Novasep develops optimised combination of separation
technologies, selectively chosen among ion-exchange, chromatography, electrodialysis, and membrane filtration, in
order to meet the purification targets and overall environmental constraints.
Success stories that we may develop in the presentation:
• Organic acids purification by Continuous Ion Exchange (succinic acid…)
• Cellulosic sugars separation and purification by industrial SSMB chromatography: C6 and C5 sugars,
separation of xylose and arabinose
• Fermentation broth clarification with ceramic membrane filtration
These examples will show how Novasep integrates and scales up the purification operations with the upstream
process, to maximize efficiency, minimize waste and improve the overall process economics.
POSTER ABSTRACTS
CARBOHYDRATE MICROARRAYS FOR MEASURING CELL WALL POLYSACCHARIDES IN RELATION
TO BIOMASS CONVERSION
L.I. Ahl, H. Zhang, H.L. Pedersen, C. Felby, and W.G.T. Willats
University of Copenhagen Rolighedsvej 23
1958 Frederiksberg C. Denmark
Wheat straw biomass (Triticum spp.) has the potential to be a new resource for biofuel production. The enzymatic
convertibility of a given type of wheat straw biomass is not only linked to the overall chemical composition, but also to
the ratio between leaf and stem. Leaf material has been found more convertible than stem material i.e. leaf material
requires a lower amount of enzymes for conversion. The leaf to stem ratio of wheat straw biomass changes with the
species, but also with the harvest and collection methods. In the Poaceae family, pectin is primarily found in the leaf.
It is therefore a good option for an indicator of the leaf to stem ratio of wheat straw biomass mixtures.
Using pectin specific monoclonal antibodies we have developed a method based on the high throughput
Comprehensive Microarray Polymer Profiling (CoMPP) technique. This new method allows us to determine the
leaf/stem ratio of wheat straw biomass by measuring the level of pectin. The method can also be applied to other cell
wall components such as hemicellulose and arabinogalactan proteins.
The CoMPP technique has been used to detect various plant cell wall polysaccharides present in the wheat straw
biomass. It has been shown that the detection levels of pectin by pectin specific monoclonal antibodies have the
ability to detect pectin values as low as 0.5% in a mixture of polysaccharides typical of that found in Poaceae species.
The polysaccharide mixture contained cellulose, β-D-glucan, or glucuronoarabinoxylan, but tests were also made on
mixtures containing both β-D-glucan, and glucuronoarabinoxylan. Pectin was added in various amounts ranging from
0% to 60% of the total mixture in order to establish the detection limits of the anti-pectin antibodies for pectic epitopes
in the mixtures. These studies were extended to determine the minimum levels of leaf material present in a Triticum
spp. harvested from various fields. Initial studies have shown the presence of pectin in mixtures containing only 10%
leaf material. A blind testing of leaf/stem ratios of Triticum spp. mixtures using the CoMPP method has also been
carried out with promising results.
SYNTHESIS AND CHARACTERIZATION OF NOVEL SOY PROTEIN-NANOCELLULOSE COMPOSITE AEROGELS
Julio Arboleda (1),Orlando J. Rojas (1,2), Lucian Lucia (1) and Janne Laine (3)
(1) NC State University, Department of Forest Biomaterials, Raleigh, NC
(2) NC State University, Department of Chemical and Biomolecular Engineering, Raleigh, NC (3) Department of Forest Products Aalto University, Espoo, Finland
Aerogels, porous materials with low density, from cellulose nanofibrils (CNF) and soy proteins (SPs) were produced
by freeze casting with the objective of optimizing the production procedure to reduce defect formation in systems with
relatively large sizes, because similar previous efforts have produced materials with dimensions limited to a few
millimeters. These newly developed green materials, which are based on two important and widely abundant
renewable resources, are unique for their low density, high surface area and low thermal conductivity, suggesting
their possible use in the design of thermal insulators, porous catalysts for chemical processes, porous filters,
packaging fillers, oil spill sorbents and flotation mechanisms.
Aerogels composed of CNF and SP with different composition were produced and characterized by compression
tests, morphology analysis, density measurements, surface area, moisture sorption from air and liquid sorption. It was
found that precursor hydrogels with initial total solids content of 8% can be easily processed into aerogels with
apparent densities on the order of 0.1 g/cm3, by slow freezing. Lower densities are expected by using more diluted
precursor systems. As the SP loading is increased, the morphology of the obtained aerogels transitions from fibrillar
to interconnected leaf-like elements.
It is demonstrated that replacement of the more expensive CNF with SP allows the production of aerogels with a
multiplicity of chemical features resulting from the amino acid contribution that maintain a high compression modulus
of 4.4 MPa even at SP loadings as high as ca. 70%. Equilibrium moisture of 4-5% of aerogels in air with 50% RH was
affected to a limited extent by the composition. The physical integrity of the aerogels was maintained upon immersion
in polar and non-polar solvents such as water and hexane, respectively. The liquid sorption rate was fast for
hydrophobic solvents in all cases and it was modulated by the chemical composition of the aerogel in water sorption
experiments, which generated swelling of the solid material after sorption. Further characterization and optimization is
required to develop industrial uses of SP-CNF aerogels; nevertheless, this first approach shows promising properties
for future actual uses of these environmentally friendly materials.
BIOMASS CHARCATERIZATION AND GASIFICATION FOR TRANSPORTATION FUELS PRODUCTION
Frank Armsteada, Christian Brodbeckb, and Sushil Adhikarib
aTuskegee University, Department of Chemical Engineering, Tuskegee, AL, 36088, U.S. bAuburn University, Department of Biosystems Engineering, Auburn, AL, 36849, U.S.
215 Tom Corley Building, Auburn, AL, 36849, U.S.
[email protected] (F. Armstead) and [email protected] (S. Adhikari)
Biomass gasification process can be used for “green” power or fuel production. Although it is relatively mature
technology compared to other thermochemical and biochemical processes, systematic studies have not been
conducted to understand the role of biomass properties on syngas composition. The purpose of this study was to
understand the effect of biomass properties on syngas quality. Six different biomasses were used: clean pine wood
chips, switchgrass pellets, peanut hull pellets, hardwood pellets, corn stover and peanut hulls. A downdraft gasifier
was used for the conversion process. Laboratory analyses were carried out to characterize the biomass with physical
and chemical properties as well as syngas composition from the gasifier. The laboratory analyses showed that peanut
hull pellets had the highest heating value whereas corn stover had the lowest heating value. Syngas results along
with carbon balance and energy analysis data will be discussed during the presentation.
LIGNIN YIELD MAXIMIZATION OF LIGNOCELLULOSIC BIOMASS BY TAGUCHI ROBUST PRODUCT DESIGN USING ORGANOSOLV FRACTIONATION
Anton Astner, Joseph J. Bozell, Timothy M. Young, David P. Harper
Center for Renewable Carbon The University of Tennessee
2506 Jacob Drive Knoxville, TN 37996
Lignin, a byproduct of the organosolv pretreatment process using lignocellulosic biomass from switchgrass (Panicum
virgatum) and tulip poplar (Liriodendron tulipifera) is currently being explored for its potential use in the production of
value-added chemicals and bio-based polymers. Pretreatment is one of the most expensive processing steps in
cellulosic biomass conversion. Optimization of the process is one of the major goals of the biomass-to ethanol
conversion process. Taguchi Robust Product Design (TRPD) provides an effective engineering experimental design
method for optimizing a system and designing products that are robust to process variations. Given the results of
several preliminary studies of the organosolv pretreatment process, four controllable design factors (inner array) were
used in the TRPD: process temperature (120°C, 140°C, 160°C), fractionation time (56 minutes, 90 minutes), sulfuric
acid concentration (0.025 M, 0.05 M, 0.1 M), and feedstock ratio (switchgrass/tulip poplar ratios of 10%/90%,
50%/50%, 90%/10%, based on both mass and volume of feedstock). Process noise was induced in the experiment by
using either the mass-based or volume-based feedstock charges of switchgrass and tulip poplar. A maximum mean
lignin yield of 78.63 wt% was found in the study. Optimum conditions for maximum lignin yield were found at a 90
minute runtime, 160°C process temperature, 0.1 M sulfuric acid concentration, and a feedstock composition of 90%
switchgrass and 10% tulip poplar. The most statistically significant factor influencing lignin yield was process
temperature. There was statistical evidence that lignin yield increased after 120°C for both feedstock charges of
switchgrass and tulip poplar (p-value < 0.0001 for mass-based, p-value < 0.0001 for volume-based). The variance in
lignin yield declined as the proportion of switchgrass increased (p-value = 0.0346 for mass-based and p-value =
0.0678 for volume-based). The finding of a local maximum for lignin yield for process temperature at 160°C suggests
that high processing temperatures are required to receive high lignin yields.
The finding, that the variance in lignin yield declined as the switchgrass percentage of feedstock increased, may
provide a pathway for other researchers interested in maximizing switchgrass use in the pretreatment process.
SCREENING OF LIGNINS BY PYROLYSIS-GAS CHROMATOGRAPHY/MASS SPECTROMETRY
Priyanka Bhattacharyaa, Thomas Elderb, Darren Bakera, Samuel Jacksonc, Timothy Rialsa, Nicole Labbéa*
a Center for Renewable Carbon
University of Tennessee, Knoxville, TN 37996 b USDA Forest Services, Southern Research Station, Pineville, LA 71360.
c Genera Energy Inc., TN
[email protected] and [email protected]
Several lignins produced commercially were characterized using pyrolysis-gas chromatography/mass spectrometry
(Py-GC/MS) technique. The research focused on characterization as well as high throughput screening of different
commercial lignins, which can be considered as potential precursor for engineering materials such as, carbon foam
and carbon fiber. Major peaks of each pyrograms were identified by matching the NIST library with mass spectral
fragmentation patterns. Syringyl (S), guaiacyl (G) and hydroxyphenyl (H) units were identified from the phenolics
originated due to the lignin fragmentation. S/G ratio was calculated based on the area of the corresponding lignin
fragments. Cellulose and hemicellulose impurities present on those lignins fragmented into smaller organic molecules
such as, acetic acid, furfural, and 2-furanmethanol during pyrolysis and were easily identified. Sugar impurities were
reported in percentage area. Principal component analysis of the chemical fingerprints of those lignins clearly showed
distinct clusters based on the feedstock characteristics.
DEHYDRATION OF PLANT DERIVED SUGARS UTILIZING IRON (III) AND MOLYBDENUM (V) CATALYSTS IN A
BIPHASIC REACTION MEDIUM
Christine M. Bohn, Mahdi M. Abu-Omar, Nathan S. Mosier
Purdue University Department of Chemistry and School of Agricultural and Biological Engineering
560 Oval Drive BOX 327 West Lafayette, Indiana 47907
Many valuable organic compounds and fuels are currently derived from a finite source of fossil derived oil. However,
by using plant material these compounds can be derived from a renewable carbon resource. The plant cell wall is
composed of three major polymers, lignin, cellulose, and hemicellulose. These polymers have the potential to yield
basic building blocks in the form of phenolic compounds (lignin) and simple sugars (cellulose, hemicellulose).
Sugars, like glucose, mannose, and xylose, can be dehydrated to form desirable platform chemicals. Transition metal
salts can be used to isomerize glucose into fructose and then facilitate the subsequent dehydration to compounds
such as 5-hydroxymethylfurfural (HMF) or levulinic acid (LA). Prior work has shown successful sugar transformation
with chromium salts, however the high toxicity of Cr makes it an undesirable choice. Inexpensiveness, abundance,
and minimal toxicity make metals like Fe and Mo attractive alternatives to Cr. By using a biphasic reaction medium,
products can be extracted into the organic layer (2-methyltetrahydrofuran) away from the aqueous catalyst to prevent
unwanted decomposition. Microwave heating techniques allow for increased reaction reactivity and selectivity. In
addition to Lewis Acid metal salts, addition of Brønsted Acids can also enhance reactivity. Metal salts, such as FeCl3
• 6H2O and MoCl5, each have an affinity for the conversion of fructose and glucose into dehydrated products and
have produced HMF, LA, and formic acid (FA) as major products. Reaction conditions can also be manipulated to
favor HMF or LA as the major product formed. Through the use of readily available metal catalysts and green
reaction solvents, optimized reaction conditions for simple sugars can soon be applied to raw biomass material.
CONVERSION OF ANAEROBIC DIGESTED GRASS INTO PHAs BY HIGH CELL DENSITY FERMENTATION
STRATEGIES.
Federico Cerrone1*, Reeta Davis1, Gearoid Duane2, Santosh Choudhari3, Eoin Casey2, Ramesh Padamati3, Kevin O’Connor1.
1School of Biomolecular and Biomedical Science, Centre for Synthesis and Chemical Biology, and Competence centre for Biorefining and Bioenergy, University College Dublin, Belfield, Dublin4, Ireland.
2School of Biochemical & Bioprocessing Engineering, University College Dublin, Belfield, Dublin4, Ireland. 3Materials Ireland, Polymer Research Centre, School of Physics, Trinity College Dublin, Dublin2 Dublin, Ireland
Grass biomass is a worldwide biome that covers 70% of the agricultural land. This biomass accounts for a 13 billion
dried metric tons value. The average composition is 25-40% cellulose (C6 polymer), 25-50% hemicellulose (C5
sugar-rich with some C6 sugars) and 10-30% lignin. The ratio of cellulose/hemicelluloses/lignin can vary according to
the grass species/maturity and seasonality of the same. The carbohydrates abundance makes it interesting for
fermentation purposes. Grass biomass can be suitable for biofuel production (bioethanol/biobutanol and biomethane)
and also for different biobased chemicals and polymers (e.g. PHA, PLA via lactic acid). The carbohydrate sugars can
be obtained with different physical, chemical, and biological pretreatments. Fermentation strategies that use
pretreated grass could be suitable substrates for bacterial fermentation to produce PHAs. However this has not been
tested to date. An integrated approach that mixed primary treatment (intended as pressing/enzyme hydrolysis) and
secondary (fermentation strategies) in a biorefining perspective was the basis of our study. In this sense we used fed-
batch strategies to achieve both high cell density (50-72 g/L) (Figure1) and PHA production in a fermentation process
with substrate coming from anaerobic digestion of grass. Mathematical models were applied to optimize the feeding
profile of such a substrate and increase PHAs productivity. PHAs monomer composition was mostly (60-70%) made
by (R)–3-hydroxydecanoic acid and (15-20%) of (R)–3-hydroxyoctanoic acid, with equal minor proportions of
hydroxhexanoic and hydroxydodecanoic acid.
Figure1. Fed-batch for high cell density fermentation.
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DILUTE ACID AND ORGANSOLV PRETREATMENT OF LOBLOLLY PINE AND SWEETGUM
William Chaplowa , Mi Lib, Maobing Tub
aAuburn University, Department of Biosystems Engineering, Auburn, AL, 36849, U.S. bAuburn University, Forest Products Lab and Center for Bioenergy and Bioproducts,
520 Devall Drive, Auburn, AL, 36849, U.S.
[email protected] (W. Chaplow) and [email protected] (M. Tu)
Forest and agricultural biomass serves as a renewable and abundant source for advanced biofuels and bio-based
chemicals production. However, the recalcitrant structure of cellulose, when combined with the lignin and
hemicellulose matrix, forms a lignocellulosic substrate that is highly resistant to enzymatic hydrolysis. Therefore,
lignocellulosic substrates must either be physically or chemically pretreated to improve accessibility to enzymes for
hydrolysis while ensuring maximum recovery of the original material. Various pretreatment methods including steam
explosion, dilute acid, ammonia fiber explosion, and organosolv processes are currently being assessed for their
ability to improve enzymatic hydrolysis. Dilute acid pretreatment is one of the most thoroughly investigated
pretreatment methods for lignocellulosic bioconversion. Organosolv is another pretreatment process that has shown
potential for producing a substrate readily hydrolyzed by cellulases while producing potentially valuable lignin-based
co-products. The solubilized lignin from this process can be used to produce valuable products such as strand binder
and polyurethane. In this study, dilute acid and organosolv pretreatments on softwood (loblolly pine) and hardwood
(sweetgum) were compared. The residual lignin in both loblolly pine and sweetgum after dilute acid pretreatment were
much higher than that from the organosolv process, but the hemicellulose content was much lower with dilute acid
pretreatment. Dilute acid pretreatment removes a significant portion of hemicellulose, whereas organosolv removes
much lignin out of both loblolly pine and sweetgum. The interaction between residual lignin/hemicellulose and
cellulase is expected to play a major role in limiting the enzymatic hydrolysis of pretreated biomass.
STUDY OF PcaV FROM STREPTOMYCES COELICOLOR YIELDS NEW INSIGHTS INTO LIGAND-RESPONSIVE MarR FAMILY TRANSCRIPTION FACTORS
Jennifer R. Davis,1,a Breann L. Brown,1,a Rebecca Page,2,* and Jason K. Sello 3,*
1Department of Molecular Pharmacology and Physiology
2Department of Molecular Biology, Cell Biology & Biochemistry 3Department of Chemistry, Brown University
Providence, RI 02912, USA MarR family proteins constitute a group of >12,000 transcriptional regulators encoded in bacterial and archaeal
genomes that control gene expression in metabolism, stress responses, virulence and multi-drug resistance. There is
much interest in defining the molecular mechanism by which ligand binding attenuates the DNA binding activities of
these proteins. Here, we describe how PcaV, a MarR family regulator in Streptomyces coelicolor, controls
transcription of genes encoding the b-ketoadipate pathway through its interaction with the pathway substrate,
protocatechuate. This transcriptional repressor is the only MarR protein known to regulate this essential pathway for
aromatic catabolism. In in vitro assays, protocatechuate and other phenolic compounds disrupt the PcaV-DNA
complex. We show that PcaV binds protocatechuate in a 1:1 stoichiometry with the highest affinity of any MarR family
member. Moreover, we report structures of PcaV in its apo form and in complex with protocatechuate. We identify an
arginine residue that is critical for ligand coordination and demonstrate that it is also required for binding DNA. We
propose that interaction of ligand with this arginine residue dictates conformational changes that modulate DNA-
binding. Our results provide new insights into the molecular mechanism by which ligands attenuate DNA binding in
this large family of transcription factors. Our findings have implications for the engineering of bacterial biorefineries.
INVESTIGATION OF POTENTIAL INHIBITORS FROM SWITCHGRASS IN BIOREFINERY
Paul B. Filson1*, Nicole Labbé1, Samuel W. Jackson1, Joon-Hyun Park2, Parthiban Radhakrishnan2 and Steven
Bobzin2
1University of Tennessee Center for Renewable Carbon
2506 Jacob Drive, Knoxville, TN 37996, USA
2Ceres, Inc. The Energy Crop Company 1535 Rancho Conejo Blvd.
Thousand Oaks, CA 91320 USA
Pretreatment of biomass prior to saccharification and fermentation into biofuels is an inseparable part in the operation
of a biorefinery. However, the yields from saccharification and fermentation processes can be negatively impacted by
the presence of phenolic compounds, non-binding inhibitors in the pretreated biomass. In this present study, after
liquid pressurized extraction of three varieties of switchgrass with water and ethanol, total phenolics equivalent of the
extractives of three varieties of switchgrass grown on a large scale in three different farms was determined at
vegetative, transition and reproductive growth stages from two growing seasons. Principal component analysis of
HPLC chromatograms of switchgrass extractives will be performed to discriminate between the switchgrass varieties
at three different growth stages. Furthermore, partial least squares regression model will also be built using
chromatograms and total phenolic equivalent to predict the total phenolic equivalent of switchgrass samples.
Statistical analysis will also be performed to assess the variability of total phenolics equivalent between the varieties
as well as impact of location where the samples were harvested. Furthermore, the relevance of the total phenolics
equivalent will be assessed on the extraction method in the processing of the biomass in a biorefinery.
PREPARATION OF OLIGO RICINOLEIC ACID DERIVATIVES VIA LIPASE-CATALYZED ESTERIFICATION AS
LUBRICANT ADDITIVES AND STAR PLYMERS FOR DRUG DELIVERY
Douglas G. Hayes
Department of Biosystems Engineering and Soil Science University of Tennessee
2506 E.J. Chapman Drive Knoxville, TN 37996-4531 USA
We have employed biocatalysis using immobilized lipases under solvent-free reaction conditions to convert ricinoleic
acid as a model hydroxyl fatty acid biorefinery derivative to produce derivatives of its oligomers. Covalent attachment
of oligo(ricinoleic acid) to polyols containing primary hydroxyl groups such as pentaerythritol produces star
polymers that possess low melting point temperatures and high viscosity indices, suggesting their used in lubrication.
Recently, we have investigated approaches to produce similar star polymers that would be more effective as drug
delivery vehicles, to allow for a greater density of oligo(ricinoleic) acyl chains extending outward from the central core,
and to possess functional groups on the termini of the chains, which will enable conjugation of hydrophilic groups,
such as poly(ethylene glycol) and its derivatives, thereby producing a unimolecular polymeric micelle. The main
approach is
to enzymatically attach 10-undecenoic acid to the termini, to incorporate a reactive terminal double bond into the
resultant product. This poster will provide an overview of the different approaches used to conduct and monitor the
progress of reaction, the latter of which was quite challenging.
POLY (LACTIC ACID)/POLY (HYDROXYALKANOATE) NONWOVENS AS BIODEGRADABLE
AGRICULTURAL MULCHES
Douglas G. Hayes1, Larry C. Wadsworth1, Sathiskumar Dharmalingam1, Karen K. Leonas2, Carol Miles3, Debra A. Inglis3, Elodie Hablot 4, and
Ramani Narayan 4
1 University of Tennessee, Knoxville, TN 37996; 2 Washington State University (WSU), 2 Pullman, WA 99164; 3 WSU Northwestern Washington Research & Extension Center,
3 Mount Vernon, WA 98273; 4 Department of Chemical Engineering and Material Science, 4 Michigan State University, East Lansing, MI 48824
Plastic agricultural mulches provide many benefits to the cultivation of specialty fruits and vegetables, including weed
prevention, water conservation, and increased soil temperature, leading to increased crop yield, hence to their
expanded use worldwide. Most mulches are prepared from polyethylene (PE), a polymer that poorly biodegrades.
The fate of PE mulches after their use is a major environmental concern. The ideal plastic mulch would be plowed
into the soil at the end of the growing season, and undergo microbial assimilation within a few months. Polylactic acid
(PLA) and polyhydroxyalkanoate (PHA), biobased polymers rthat can readily be produced in the biorefinery, are
potentially valuable “biodegradable” mulch materials. Nonwovens prepared PLA and PLA / PHA blends, materials
with high strength and low weight, have been prepared and analyzed through several experimental platforms: soil
burial studies conducted in greenhouses, long-term studies conducted in open fields and high tunnels at three diverse
U.S locations,
weatherometry, and inherent biodegradability analyzed by standardized tests. PLA/PHA mulches prepared via
meltblown nonwovens processing undergo extensive degradation, resulting in a decrease of molecular weight (~25%)
due to the cleavage of ester bonds (FTIR spectroscopy) and a loss of > 50% tensile strength during a 30 week period,
as observed in soil burial studies. Soil temperature,moisture, and ultraviolet light intensity are the most important
environmental parameters to induce biodegradation in the soil burial studies.
INFLUENCE OF FEESTOCK DECONSTRUCTION IN ENZYMATIC SACCHARIFICATION OF SOFTWOODS
Ingrid C. Hoeger,1,2 Sandeep S. Nair,2,3 Orlando J. Rojas,1 Junyong–FS Zhu2
1North Carolina State University, Forest Biomaterials, campus Box 8005, Raleigh, NC 27695,
2USDA Forest Service, Forest Products Lab, One Gifford Pinchot Dr., Madison, WI 53726 3Georgia Tech, Department of Chemistry, Atlanta, GA
The past decade has witnessed a rapid progression biorefinery research; among the most important fundamental
questions regarding bioconversion of biomass is the effect of size and surface area, for example, for the efficient
enzymatic saccharification of wood. In this investigation we elucidate the effect of biomass deconstruction in the
enzymatic hydrolysis of wood. Unbleached softwood mechanical pulps and bleached Kraft pulps were deconstructed
through a continuous grinding system in a SuperMassCollider®. The mechanical deconstruction of the cell wall to the
micro or nano size was followed by energy consumption and the resultant fiber morphology assessed via SEM and
AFM. Samples of the process were treated with a mixture of enzymes and the generation of glucose and
oligosacccharides was analyzed. It was found that almost all cellulose from the bleached softwood was converted to
glucose after only 15 min of fibrillation with a cellulase loading of 5 FPU/g glucan. In the case of the unbleached
samples, under same cellulase loading it took six fibrillation hours in order to reach 55% cellulose conversion. The
differences are explained by the negative effect of lignin and residual cell wall components in enzymatic conversion.
Overall, we will discuss the effect of cell wall deconstruction in saccharification and also in the production of value
added materials, such as nanopaper.
OXIDATIVE STABILIZATION STUDIES IN THE FORMATION OF ELECTROSPUN CARBON NANOFIBERS FROM A PURIFIED SOFTWOOD KRAFT LIGNIN
Omid Hosseinaei, Darren A. Baker*
University of Tennessee
2506 Jacob Dr. Knoxville, TN, USA
Lignin, as the second most abundant natural polymer, has gained attention for the production of carbon fibers. Lignin-
based carbon fibers will be inexpensive compared to petroleum-based carbon fibers and will therefore increase the
application of carbon fibers. Electrospinning is a simple and relatively inexpensive way to produce continuous nano-
scale carbon fibers. Electrospun fibers have broad applications in filtration media, nanocomposites, pharmaceutical
compositions and protective clothing. The high surface area to volume ratios of electrospun carbon nanofibers, which
can be increased by activation, make them a good choice for use in energy applications.
Oxidative stabilization can be considered as the most important step in the process of making carbon fiber. Lignin is a
thermoplastic material and oxidative stabilization is needed to prevent the fusion of fibers during carbonization.
Stabilization is achieved by oxidatively heating the fibers (historically at a rate of 0.01 to 0.2°C/min to between 200
and 250°C) to cause the cross-linking and condensation of lignin. The heating rate used during stabilization is such
that the treatment temperature always remains below glass transition temperature (Tg) of lignin which gradually
increases during stabilization. Therefore, in contrast to technical lignins used in the past, the lignins used for this
study were optimized to have a high Tg, so that oxidative stabilization of the lignin would proceed at a much faster
rate.
A commercial kraft softwood lignin was used for making electrospun carbon nanofibers. The lignin was first purified to
remove any residual ash, carbohydrates and low molecular weight (MW) components. The purified lignin was then
sequentially solvent extracted to obtain two lignins of differing Tg, and therefore MW. The high molecular weight lignin
after extraction had a high Tg as measured by differential scanning calorimetry. Electrospinning solutions were
prepared by dissolving this lignin in a mixture of two solvents optimized for lignin dissolution.The solutions were
electrospun using a syringe pump, rotating target and a potential difference between the two. The electrospun lignin
fibers were oxidatively thermostabilized at differing heating rates and were then anaerobically carbonized to 950°C.
The stabilization and carbonization yields were calculated for each sample. The chemical and thermal properties of
the stabilized fibers were studied by infrared spectroscopy and thermogravimetric analysis, while the morphology of
the carbon fiber webs was examined by scanning electron microscopy.
CHARACTERIZATION OF ORGANOSOLV SWITCHGRASS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY/MULTIPLE STAGE TANDEM MASS SPECTROMETRY USING HYDROXIDE-DOPED
ELECTROSPRAY IONIZATION
Tiffany M. Jarrell, † Christopher L. Marcum,† Benjamin C. Owen,† Laura J. Haupert,† Trenton H. Parsell,† Mahdi M. Abu-Omar,† Joseph J. Bozell,‡ and Hilkka I. Kenttamaa†
† Purdue University, Department of Chemistry
560 Oval Drive West Lafayette, Indiana 47907, United States
‡ University of Tennessee, Center for Renewable Carbon
2506 Jacob Drive Knoxville, Tennessee 37996, United States
Many research efforts focus on the extraction, degradation and catalytic transformation of lignin, hemicellulose and
cellulose. Unfortunately, these processes result in the production of very complex mixtures. Testing the usefulness of
these processes requires analytical methods that can be used to rapidly characterize the complex mixtures produced.
In this study, high-performance liquid chromatography/multiple stage tandem mass spectrometry has been
implemented for organosolv mixtures of switchgrass. In this study, HPLC coupled with negative-ion mode MSn
analysis for the characterization of lignin degradation products is demonstrated. This approach hinges on the use of a
hydroxide doped electrospray ionization method that ionizes all the mixture components to only yield one ion/analyte
with no fragmentation. Analytes eluting from the HPLC were detected by UV light absorbance by using a PDA
detector and by detecting all the ions generated upon ESI in the mass spectrometer. In addition to the acquisition of
mass spectra for the compounds eluting from HPLC (MS1), ions formed from these compounds were subjected to
isolation and CAD experiments (up to MS3) until no further fragmentation products were observed. MSn was utilized to
provide structural information for the components of a real degradation mixture on a chromatographic time scale. On
the same time scale, elemental compositions were acquired for all analytes by transferring ions to a high-resolution
instrument. This methodology significantly improves the ability to analyze complex product mixtures that result from
degraded biomass. A switchgrass degradation product mixture was analyzed and molecular structures were
proposed for its main components. The mixture contains primarily coumaric and ferulic esters. These unextracted
components prevent the analysis of the lignin components in the mixture due to their high abundance. Further
modification to the extraction procedure would need to be made before complete analysis of the lignin components
can be accomplished.
THE EFFECTS OF ORGANOSOLV FRACTIONATION PROCESS ON THE PROPERTIES OF SWITCHGRASS LIGNIN AS A PRECUSOR FOR CARBON PRODUCTS
Pyoungchung Kim1, Nicole Labbé1, Darren Baker1, Charles W. Edmunds1. Timothy G. Rials1
1 Center for Renewable Carbon 2506 Jacob Drive
University of Tennessee, Knoxville, TN 37996
We have investigated organosolv fractionation of switchgrass in order to produce lignin as a precursor for carbon
products. The fractionation was accomplished with an organic solvent-aqueous mixture containing water (50%),
ethanol (34%), methyl isobutyl ketone (MIBK, 16%) and 0.06% sulfuric acid. Processing factors were temperature
(140 – 180 oC) and reaction time (10 – 80 min) under 1,700 psi of pressure. After fractionation of switchgrass into
solid and solvent fraction, mass balance of cellulose, hemicellulose and lignin was estimated by solid fraction. Mass
loss of solid fraction showed a gradual increase by reaction time under different temperature and presented a loss up
to 45 % at 140 oC, 55 % at 160 oC and 64 % at 180 oC for 60 min reaction time. Of the solid fraction, cellulose
decreased less than 3 % under 140 oC and 7 % under 160 oC for 60 min, whereas linearly decreased to 30 % under
180 oC for 60 min. Hemicellulose fraction significantly decreased for 60 min to 78 % under 140 oC, 88 % under 160 oC
and 95 % under 180 oC. Simultaneously, lignin fraction also decreased to 72 % under 140 oC, 87 % under 160 oC,
whereas significantly decreased to 87 % for 30 min and did not decreased by time under 180 oC. Surface functionality
of solid fraction also showed a significant decrease with increasing reaction time. Lignin extracted from the liquid
fraction was characterized by TGA and showed a typical shape of herbaceous biomass lignin. Characteristics of lignin
surface functionality in lignin by FTIR showed that lignin produced at 180 oC contained slightly higher carbonyl group
that derived from oxidation of phenylpropane unit in the lignin. S/G ratio calculated by FTIR was not significantly
different at both temperatures. We concluded with the suggestion that optimized operation conditions to produce
lignin and cellulose for organosolv fractionation were 160 oC for 60 min or 180 oC for 30 min.
ACTIVATION OF LIGNOCELLULOSIC BIOMASS IN IONIC LIQUIDS
Lindsey Kline1, Nicole Labbé1,Keonhee Kim1, Luc Moens2, John Yarbrough2,
1Center for Renewable Carbon The University of Tennessee
2506 Jacob Drive Knoxville, TN 37996
2National Renewable Energy Laboratory
1617 Cold Blvd Golden, CO 80401
With the growing interest in utilizing renewable carbon from lignocellulosic biomass, improved activation and
fractionation processes are needed to establish viable biorefineries by providing saccharide streams for production of
fuels and a lignin fraction for the production of high value co-products such as carbon fibers. This study includes
analysis of three feedstocks (switchgrass, hybrid poplar, and pine) after activation in ionic liquid at low temperatures.
The biomass is first partially dissolved in the ionic liquid and regenerated with a co-solvent prior to analysis. This ionic
liquid approach has shown to include physio-chemical changes to the biomass cell wall, including a decrease in the
cellulose crystallinity and deacetylation of the biomass. A series of characterization techniques will follow to compare
the feedstocks before and after activation, including infrared spectroscopy and corresponding statistical classification
techniques, classical wet chemistry methods for determination of chemical composition, calculation of syringyl to
guaiacyl ratio, Pyrolysis Gas Chromatography/Mass Spectrometry (PyGC/MS), and electron microscopy. Through
comparison of the herbaceous, hardwood, and softwood bioenergy feedstocks, a better understanding of the
activation process and resulting pretreated biomass ideally precedes enzymatic conversion of the cellulose and
hemicellulose fractions, allowing for isolation of lignin with minimal structural changes
A FUNDAMENTAL STUDY OF THE FRAGMENTATION OF SMALL MOLECULES RELATED TO LIGNIN VIA
COLLISION-ACTIVATED DISSOCIATION (CAD)
Christopher L. Marcum1, Benjamin Owen1, Tiffany Jarrell1, Laura Haupert2, Hilkka I. Kenttämaa1
1Department of Chemistry Purdue University
560 Oval Dr. West Lafayette, IN 47907
2OMI Industries
1300 Barbour Way Rising Sun, IN 47040
In the search for a replacement for fossil fuels and other valuable chemicals which are currently obtained only from
crude oil, lignocellulosic biomass and its catalytic transformation and degradation products have become of particular
interest as a renewable alternative. In order to study the degradation and catalytic transformation products of lignin, a
large component of lignocellulosic biomass, negative-ion mode electrospray ionization, (-)ESI, tandem mass
spectrometry has been utilized as it allows for the structural elucidation of the complex product mixtures created.
However, the fundamental mechanisms by which many of these negative ions fragment upon collision-activated
dissociation (CAD) are very poorly understood. In order to study the fragmentation pathways of lignin degradation
products several model compounds relevant to these products were selected. These compounds were introduced
into a linear quadrupole ion trap (LQIT) mass spectrometer via (-)ESI with a sodium hydroxide dopant and subjected
to CAD. The model compounds studied exhibited unique fragmentation patterns that allow for their identification in
complex mixtures. Common fragmentation products (and the functionality present) formed upon CAD include: methyl
radical (methoxy), ethyl radical (ethoxy), carbon monoxide (phenol), and carbon dioxide (carboxylic acid). In order to
better understand the mechanisms by which these compounds fragment via CAD several interesting fragmentation
pathways were studied in more depth using additional model compounds and isotopic labeling. One of these
observed pathways that proved to be of particular interest was the formation of neutral methanol upon fragmentation
of several of the selected model compounds, which contained both carboxylic acid and methoxy functionalities. This
particular fragmentation pathway was examined using isotopic labeling as well as through the study of model
compounds with differing methoxy and carboxylic acid functionalization. Based upon these studies 4-hydroxy-3,5-
dimethoxybenzoic acid (one of the studied compounds) is believed to form the 5-methoxy-1,3-didehydrophenoxide
anion following the loss of carbon dioxide and methanol. The fragmentation pathways and proposed fragmentation
mechanisms will be presented for this compound as well as many others studied. Future work will focus on the
integration of these fragmentation pathways into a searchable library for the identification of compounds in unknown
complex mixtures.
METHODS FOR THE IDENTIFICATION OF LEVOGLUCOSAN ISOMERS IN BIO OIL OBTAINED BY FAST PYROLYSIS OF CELLULOSE
James S. Riedeman, Linan Yang, Mckay Easton, John J. Nash, Vinod Kumar Venkatakrishnan,
and Hilkka I. Kenttämaa
Department of Chemistry, Purdue University 560 Oval Drive, West Lafayette, IN United States
School of Chemical Engineering, Purdue University
Forney Hall of Chemical Engineering, 1060 480 Stadium Mall Drive, West Lafayette, IN United States
Fast pyrolysis is widely perceived as a promising approach to convert biomass into fuels. Previous research results
demonstrated that the primary products formed in fast pyrolysis of cellulose are small molecules, mostly one
dehydrated glucose building block monomer. Levoglucosan has been proposed to be the major product yet definitive
evidence has yet to be obtained. Identification of the monomer structure(s) is of great importance in identification of
the best conditions for pyrolytic conversion of biomass into useful chemicals or hydrocarbon fuels. By performing
LC/MS on a Thermo Fisher Scientific LTQ affixed with a C-18 4 X 250 mm analytical column, we developed LC
methods that were successfully applied to preparatory HPLC for the isolation of a pure component of pyrolysis oil.
NMR characterization of this component and cross comparison with commercially available levoglucosan
(synthesized and isolated from pyrolysis of starch) showed a good match. However peak splitting was not adequate
for obtaining coupling constants and thus stereochemistry has not yet been determined. Computational results have
shown other isomers to be lower in energy than levoglucosan. Therefore, further characterization is imperative. XRD
crystallography is a potential method for obtaining the actual structure of the primary isomer. The other approach that
we used in the identification of the monomer structure(s) is to synthesize levoglucosan from glucose to keep the
stereochemistry of levoglucosan. This product will be compared to the structure(s) of bio oil monomer using high
resolution NMR to determine if they match.
LIGNIN-SOY PROTEIN INTERACTIONS: ELECTROSPUN NANOFIBERS BASED ON SOY PROTEINS AND LIGNIN
Carlos Salas1,*, Mariko Ago1, Orlando J. Rojas1,2
1Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695-8005, USA
2Faculty of Chemistry and Materials Sciences, Department of Forest Products Technology Aalto University P.O. Box 16300
FI-00076, Aalto, Finland
The applications of lignin different than power generation include those that take advantage of its chemical features
as well as its physical and thermal properties when combined with other (bio)polymers, for example in biocomposites.
Development of such materials requires a thorough understanding of surface and intermolecular interactions. This
work summarizes the results of our investigation on the interactions of lignin and soybean proteins (SPs) and the
development of electrospun nanofibers. The adsorption on lignin from aqueous solution of the two main proteins in
soybean, glycinin and beta conglycinin, was studied by quartz crystal microgravimetry and surface plasmon
resonance under different physicochemical environments (native conditions as well as in denatured forms).
Compared to results using cellulose and hydrophilic surfaces, a larger protein adsorption was observed on lignin
substrates. The water contact angle (WCA) revealed an increased hydrophilicity of the surface upon protein
adsorption, with typical reductions in WCA of ≈ 35°. This observation highlights the role of hydrophobic interactions
between lignins and proteins as driving mechanism for adsorption. To exploit further these interactions,
electrospinning technique was used to produce nanofibers from lignin and soy proteins. Scanning electron
microscope (SEM) imaging revealed that defect-free fibers (171±16 nm) were produced after addition of polyethylene
oxide as coadjutant. Overall, these two polymers are proposed as platforms for development of new materials taking
advantage of the fact that they are readily available, inexpensive and interact effectively in multicomponent systems.
RAPID CHARACTERIZATION AND DETERMINATION OF WOOD CHEMISTRY AND CRYSTALLINITY INDEX OF LOBLOLLY PINE
Kelvin Smith, Brian K. Via, Wei Jiang, Lori Eckhardt
Auburn University Biosystems Engineering and School of Forestry and Wildlife Sciences
520 Devall Drive Auburn, Alabama, United States
[email protected] (K. Smith) & [email protected] (B. Via)
Rapid characterization of wood chemistry and crystallinity index for 200 loblolly pine trees was performed with near
infrared spectroscopy (NIR) and Fourier transform infrared reflectance spectroscopy (FT-IR) spectroscopy,
respectively. Loblolly pine is the most common type of southern pine in the southeastern region of the United States
and was thus utilized for this study. NIR spectroscopy coupled with multivariate modeling was employed to measure
the percent chemical composition for each of the 200 samples’ for 14 families including lignin, cellulose, hemicellulose
and extractives. The distribution metrics such as the mean and standard deviation for lignin, cellulose, hemicellulose
and extractives was similar to that reported in the literature and all followed a normal distribution. The ratio of
absorbance for crystalline (1428 cm-1) and amorphous cellulose (898 cm-1) associated wavelengths was utilized to
infer the crystallinity index. For application, it is suggested that trees from families of low lignin, high cellulose, and
high crystallinity index could be partitioned for high value end products while higher lignin trees/families could be
utilized for bioenergy feedstock. Future work will consist of validating the NIR models by performing wet chemistry
on a subsample of the population in this study. Additionally, funds will be sought to validate the crystallinity index
with the more conventional x-ray diffraction method.
INTEGRATED PROCESS, FINANCIAL, AND RISK MODELING OF CELLULOSIC ETHANOL FROM WOODY AND NON-WOODY FEEDSTOCKS VIA DILUTE ACID
PRETREATMENT
Trevor Treasure, Ronalds Gonzalez, Hasan Jameel, Richard B. Phillips, Steve Kelley
North Carolina State University Department of Forest Biomaterials
2820 Faucette Dr. Raleigh, NC, USA
Dilute sulfuric acid pretreatment followed by enzymatic hydrolysis and fermentation is a technology widely studied as
a potential pathway for conversion of lignocellulosic biomass to ethanol. Six feedstocks, three woody and three non-
woody, were evaluated in process and financial simulations. The woody feedstocks include natural hardwood,
Eucalyptus, and loblolly pine while the non-woody feedstocks include corn stover, switchgrass, and sweet sorghum.
A complete process model was developed in WinGEMS which provided the material and energy balances necessary
for financial analysis. Based upon experimental and literature data, ethanol yields for the non-woody feedstocks
range from 321-330 liters per bone dry metric ton of biomass (L/BDt). Sweet sorghum that has been pressed and
washed to remove soluble sugars prior to dilute acid processing can have an ethanol yield of approximately 471
L/BDt but additional front end capital expenditure (CAPEX) is required to modify the traditional dilute acid process.
Natural hardwood and Eucalyptus produce ethanol yields of 342 and 317 L/BDt respectively. Loblolly pine is
especially recalcitrant and only yields 108 L/BDt, this feedstock produces excess electricity of approximately 440
kWh/BDt biomass processed.
When processing 700k bone dry metric tons per year, the non-woody feedstocks have lower minimum ethanol
revenues to achieve a 12% internal rate of return (MER@12%) than the woody feedstocks. The non-wood MER@12%
ranged from $0.69-$0.77/liter while the MER@12% for natural hardwood and Eucalyptus was $0.82/liter. The MER@12%
for loblolly pine is higher than reasonable limits at $2.25/liter due to the low ethanol yield. The risk analysis of this
technology and feedstocks indicates that financial success is generally driven by ethanol revenue, biomass cost, and
ethanol yield although loblolly pine is especially sensitive to electricity whole sale price. The impact of feedstock
composition variability on the net present value (NPV@12%) was estimated for corn stover, switchgrass, and loblolly
pine. One standard deviation in the sample carbohydrate content for corn stover, switchgrass, and loblolly pine will
impact the NPV@12% by approximately $40M, $60M, and $24M respectively. If recent historical cost and revenue
variability continues for the life of the project the most attractive feedstock is squeezed sweet sorghum where the
probability of achieving at least a 12% internal rate of return is 64%. The likelihood of attaining at least a 12% internal
rate of return for the other biomass types through this conversion pathway is low enough to discourage financial
investment under the current assumptions.
FLOWABILITY OF GROUND LOBLOLLY PINE
Jacob Wadkins, Anshu Shrestha, Oladiran Fasina
Auburn University, Department of Biosystems Engineering, Auburn, AL, 36849, U.S. 214 Tom Corley Building, Auburn, AL, 36849, U.S.
[email protected] (J. Wadkins) and [email protected] (O. Fasina)
Biomass, such as wood chips, is a bulk material and therefore has the typical flow problems associated with bulk
materials. Different material properties of ground loblolly pine chips were tested to quantify their effect on the
flowability of the chips; the properties tested were feedstock type (clean, dirty, residue), particle size (ground through
1/8” and 1/16” screens), and moisture content (10% and 30% w.b.). All samples were run through a series of tests
including a flow test which calculated the hopper half angle and outlet diameter of a hopper required for mass flow of
the wood chips. These dimensions were used as parameters for comparing the effects of the material properties of
the chips on their flowability. Results obtained show that flowability generally improved for ground clean chips with an
increase in particle size. At the smaller particle size (i.e. samples ground through the 1/16” screen), the ground “dirty”
chips had the best flow properties of the three different types of samples. At the larger particle size (i.e. samples
ground through the 1/8” screen), the flowability of ground clean and dirty chips were similar while the residues’
flowability was the worst. Experimentation on the effect that moisture content has on flowability is currently ongoing
and the results will be discussed during the presentation.
GAS-PHASE HIGHER ALCOHOL SYNTHESIS AND FISCHER TROPSCH SYNTHESIS
Liana Wuchte a, Charlotte Stewartb, David Roeb, and Christopher Robertsb
aAuburn University, Department of Biosystems Engineering, Auburn, AL, 36849, U.S. bAuburn University, Department of Chemical Engineering,
210 Ross Hall, Auburn, AL, 36849, U.S
[email protected] (L. Wuchte); [email protected] (R. Roberts)
Studies of the Fischer Tropsch synthesis (FTS) reaction have gained popularity in recent years for its possible
application in biofuel technology and special chemical production from syngas produced by the gasification process.
This particular experiment set contained several major objectives in relation to the study of FTS: conducting a higher
alcohol synthesis reaction (a very comparable reaction to FTS) to study the effects of altering the syngas composition
to find an optimal ratio of H2 to CO for the synthesis of the desired higher alcohol product, preparing and promoting
catalyst for future FTS experiments using both the incipient wetness and wetness impregnation methods, energy
dispersive x-ray spectroscopy (EDS) testing the newly promoted catalyst to judge the effectiveness of the loadings,
and analyzing the product sample from a past FTS reaction performed two months earlier to test for aldehyde and
ketone content. Compositional testing showed incipient wetness was overall less effective (in this case) than wetness
impregnation. Analysis also hinted that the FTS sample tested contained a negligible amount of aldehydes and no
ketones, but further studies are necessary to confirm this conclusion. This presentation will discuss the results
obtained from the FTS reaction for higher alcohol synthesis and the lessons learned during the 10-week summer
internship as a SEED fellow.
ANALYSIS OF NOVEL LIGNIN EXTRACTED FROM “MELT COMPOUNDED” BIOMASS
Wei Zhang1,3, Charles E. Frazier1,3, Justin R. Barone2,3, and Scott Renneckar1,3
Departments of Sustainable Biomaterials1, Biological Systems Engineering2, and the Macromolecules and Interfaces Institute3
Virginia Tech
230 Cheatham Hall Blacksburg, VA
Lignin fractionation from biomass, in good yield and with little modification, is a key challenge to produce biobased
value-added components from lignocellulose. The purpose of this study was to investigate the novel characteristics of
extracted lignin from “melt compounded” wood. Pretreatment of sweet gum (Liquidambar styraciflua) using industrially
proven polymer-processing equipment with a non-toxic solvent enabled the disruption of the recalcitrant wood cell
wall, resulting in high-yield lignin extraction. Nine different pretreatment severities were used to explore the impact of
processing on the extracted lignin structure. Quantitative 31P and 1H nuclear magnetic resonance spectroscopies,
along with thioacidolysis were the main tools to illustrate the isolated lignin functionality and structure. Additionally,
size exclusion chromatography analysis was used to determine the molecular weight for the isolated lignin. Overall,
extracted lignin from the pretreated biomass exhibited a high molecular weight, a minimum amount of condensed
phenolic groups, and a minimum amount of carboxylic acid groups. Hence, the melt compounding pretreatment of
biomass offers a route to fractionate and recover lignin in good yields from biomass that has functionality and
structure with minimal modification compared to other pretreatment methods such as dilute acid and organosolv
pretreatment methods.