introduction to green chemistry mary kirchhoff associated colleges of the chicago area 16 september...
TRANSCRIPT
Introduction to Green Chemistry
Mary Kirchhoff
Associated Colleges of the Chicago Area
16 September 2003
Green Chemistry
Green Chemistry is the design of chemical products and processes that reduce or eliminate the use and/or generation of hazardous substances.
Historical Approach to Environmental Problems
Waste treatment, control, and disposal; pollutant monitoring; hazardous waste site cleanup.
Development of standards for emissions to air, releases to water, and disposal by land, as well as regulation of these standards.
“Command and Control”
Growth in Environmental Regulation
AMFAARPAA
AJAASBCAA
ESAA-AECAFFRAA
FEAPRAIRA
NWPAACODRA/NMSPAA
FCRPAMMPAA
120
110
100
90
80
70
60
50
40
30
20
10
01870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
EPACTFFCACERFACRAA
PPAPPVAIEREAANTPAGLCPAABACZARAWRDAEDPOPARECACAAAGCRAGLFWRAHMTUSANEEA
SDWAASARA
BLRAERDDAAEAWANOPPAPTSAUMTRCAESAAQGANCPA
TSCAFLPMARCRANFMACZMAA
NEPAEQIACAAEPAEEAOSHAFAWRAANPAA
FRRRPASOWADPA
WSRAEARCFHSA
AQA
NAWCA
WQA
NWPA
MPRSAAARPA
HMTA
FCMHSA
NHPA
WLDAFWCAA
FWAAEA
AEPA FIFRA PAA
FAWRAMBCANPSWA
IANBRA
AARHAYA
TAFWCA
BPA
NLRAWPA
AQAFOIA
WRPAAFCA
FHSANFMUA
BLBAFWPCAMPRSA
CZMANCA
FEPCAPWSAMMPA
ESATAPA
RCRAAWLDI
APASWDA
CERCLACZMIA
COWLDAFWLCA
MPRSAA
CAAACWA
SMCRASWRCASDWAA
Nu
mb
er
of
Law
s
Environmental Expenditures& Economic Sustainability
Source: R. R. Bezdek., MISI - 1999
0
50
100
150
200
250
1970 1980 1990 1998
Year
$ (
in B
illi
on
s)
Pollution Prevention Act of 1990
PollutionPrevention
SourceReduction
Recycling
Treatment
Disposal
Green Chemistry
Green Chemistry is the design of chemical products and processes that reduce or eliminate the use and/or generation of hazardous substances.
Characterization of Environmental Problems
Risk = f(hazard x exposure)
Traditionally, risk management has focused on exposure rather than hazard.
Circumstantial vs. IntrinsicRecognize hazard as a design flaw
Circumstantial Use Exposure Handling Treatment Protection Recycling Costly
Intrinsic Molecular design for
reduced toxicity Reduced ability to
manifest hazard Inherent safety from
accidents or terrorism Increased potential
profitability
Why Green Chemistry? “Business is going to get significantly more profitable
through the application of green technology. Proactive companies are finding the theme ‘good for business’ to be credible and real.”
Paul V. Tebo, Vice President for Safety, Health, and Environment, DuPont
We have found that voluntary environmental improvements - as encouraged by programs like EPA’s Green Chemistry Challenge ... - can return as much as 53% on capital, compared with a negative 16% when improvements are mandated by law.”
William S. Stavropoulos, President and Chief Executive Officer, The Dow Chemical Company
Presidential Green Chemistry Challenge
Goal: To promote pollution prevention and industrial ecology through a new EPA Design for the Environment partnership with the chemical industry.
Challenge: To find cleaner, cheaper, and smarter ways to manufacture the products that we depend on.
Presidential Green Chemistry Challenge Awards
Alternative synthetic pathwaysAlternative reaction conditionsDesigning safer chemicalsAcademicSmall business
Twelve Principles of Green Chemistry 1. Prevention 2. Atom Economy 3. Less Hazardous Chemical Syntheses 4. Designing Safer Chemicals 5. Safer Solvents and Auxiliaries 6. Design for Energy Efficiency 7. Use of Renewable Feedstocks 8. Reduce Derivatives 9. Catalysis 10. Design for Degradation 11. Real-time Analysis for Pollution Prevention 12. Inherently Safer Chemistry for Accident Prevention
Principle 1
It is better to prevent waste than to treat or clean up waste after it is formed.
Redesign of the Sertraline Process
Sertraline: active ingredient in ZoloftCombined process
Doubled yieldEthanol replaced CH2Cl2, THF, toluene, and
hexaneEliminated use of 140 metric tons/year TiCl4Eliminated 150 metric tons/year 35% HCl
Pfizer
Redesign of the Sertraline Process
TiCl4/ MeNH2
Cl
Cl
NMe
Cl
Cl
NMe
Cl
Cl
NMeCl
Cl
O
Cl
Cl
NMe
MeNH2
EtOH
Cl
Cl
NMe
Cl
Cl
NMe
EtOAcHCl
EtOAcHCl
Cl
Cl
NMe
Cl
Cl
NMe
toluene/hexanesTHF
Pd/C, H2
+ TiO2
+ MeNH4Cl
(D)-mandelic acidEtOH
"imine"isolated
racemis mixture cis and trans isomers
Sertraline Mandelateisolated
Sertralineisolatedfinal product
"imine" not isolated
racemic mixture not isolated
PdC/CaCO3
H2/EtOH
MeOH rex
(D)-mandelic acidEtOH
Sertralineisolated final product
Sertraline Mandelateisolated
+ H2O
Principle 1: Waste prevention
Cytovene antiviral agent used in the treatment of
cytomegalovirus (CMV) retinitis infections AIDS and solid-tissue transplant patients
Improved synthesis reduced chemical processing steps from 6 to 2 reduced number of reagents and intermediates
from 22 to 11 eliminated 1.12 million kg/year liquid waste eliminated 25,300 kg/year solid waste increased overall yield by 25%
Principle 2
Synthetic methods should be designed to maximize
the incorporation of all materials used into the final
product.
Principle 2: Atom economy
Traditional synthesis of ibuprofen 6 stoichiometric steps <40% atom utilization
(CH3CO)2O AlCl3
O
ClCH2CO2C2H5
NaOC2H5
O CHCO2C2H5
H+
H2O
CHO
H2NOH
CH NOH
CN CO2H
Ibuprofen
Principle 2: Atom economy
Catalytic synthesis of ibuprofen 3 catalytic steps 80% atom utilization (99% with recovered acetic acid)
BHC
(CH3CO)2O HF
O
H2
catalyst
OH
CO, Pd
CO2H
Ibuprofen
Principle 3
Wherever practicable, synthetic methodologies
should be designed to use and generate substances that possess little or no
toxicity to human health and the environment.
Principle 3: Non-toxic substances
Disadvantages phosgene is toxic, corrosive requires large amount of CH2Cl2 polycarbonate contaminated with Cl impurities
Polycarbonate Synthesis: Phosgene Process
OH OHCl Cl
O
+NaOH
O O *
O
* n
Principle 3: Non-toxic substances
OH OH
+ O O *
O
* n
O O
O
Advantages diphenylcarbonate synthesized without phosgene eliminates use of CH2Cl2 higher-quality polycarbonates
Komiya et al., Asahi Chemical Industry Co.
Polycarbonate Synthesis: Solid-State Process
Alternative Synthetic PathwaysSodium iminodisuccinate
Biodegradable, environmentally friendly chelating agent
Synthesized in a waste-free processEliminates use of hydrogen cyanide
Bayer Corporation and Bayer AG
2001 Alternative Synthetic Pathways Award Winner
O
O
O
NaOH NH3 ONa
ONaNaO
NaON
H
O O
O O
Principle 4
Chemical products should be designed to preserve efficacy of function while
reducing toxicity.
Principle 4: Reduce Toxicity
Spinosad: a natural product for insect control produced by Saccharopolyspora spinosa isolated from Caribbean soil sample demonstrates high selectivity, low toxicity
Dow AgroSciences
OO
H
O
HH
HH
OMe
OMe
OMe
O
O
OO
R
Me2N
Spinosyn A: R = HSpinosyn D: R = CH3
Designing Safer Chemicals
Cationic electrodeposition coatings containing yttriumProvides corrosion resistance to
automobilesReplaces lead in electrocoat primersLess toxic than lead and twice as effective
on a weight basis
PPG Industries2001 Designing Safer Chemicals Award Winner
Small Business Award
PYROCOOL Technologies, Inc.PYROCOOL F.E.F. (Fire Extinguishing
Foam)0.4% aqueous mixture of highly
biodegradable nonionic surfactants, anionic surfactants, and amphoteric surfactants
replacement for halon gases and aqueous film forming foams (AFFFs)
ACQ Wood Preservatives Pressure-treated lumber
7 million board feet/yearchromated copper arsenate (CCA) preservative
40 million pounds of arsenic 64 million pounds of hexavalent chromium
Alkaline Copper Quaternary (ACQ) wood preservative
Bivalent copper complex plus quaternary ammonium compound dissolved in ethanolamine of ammonia
Virtually eliminates use of arsenic in USAvoids production, transportation, use, and disposal risks
associated with CCA Chemical
Specialties, Inc.
Principle 5
The use of auxiliary substances (e.g. solvents,
separation agents, etc.) should be made
unnecessary wherever possible and, innocuous
when used.
Principle 5: Benign solvents
Carbon-carbon bond formation in water Diels-Alder, Barbier-Grignard, pericyclic
Indium-mediated cyclopentanoid formationLi, Tulane University
R2
O O Cl Cl
base
O
R2
O
Cl
R1
R1In/H2O
OH
R2
OR1
Research to Commercialization: Thomas Swan & Co Ltd
Multi-purpose plant using supercritical fluidsFirst full-scale facility for continuous, multi-purpose
synthesis, includingHydrogenationsFriedel-Crafts reactionsHydroformylationsEtherifications
Technology developed with the University of Nottingham
Reactions in Supercritical Fluids
Formation of cyclic ethersHydrogenation
Poliakoff, University of Nottingham
HO OH
acid catalyst
O+ H2O
NO2 NH2Pd or Pt catalyst
propane, 80 bar
150-250 0C
CO2 for Dry Cleaning
Dry Cleaningcurrent process uses perc
(perchloroethylene), a suspected carcinogen and groundwater contaminant
new process uses liquid carbon dioxide, a nonflammable, nontoxic, and renewable substance
Non-Fluorous CO2-Philic Materials
Replacement for expensive, persistent fluorous CO2-philes
New CO2-philes needed to expand commercial
applications of CO2
Poly(ether-carbonates)Lower miscibility pressures than perfluoropolyethersBiodegradable100 times less expensive
Beckman, University of Pittsburgh
Principle 6
Energy requirements should be recognized for their
environmental and economic impacts and should be
minimized. Synthetic methods should be conducted at ambient
temperature and pressure.
Principle 6: Minimize energy usage
Catalytic synthesis of ULTEM® thermoplastic resin 25% less energy required to produce each pound
of resin volume of organic waste stream for off-site
disposal decreased by 90% 50% less catalyst used
GE Plastics (General Electric Corporation)
Alternative products
Thermal Polyaspartic Acid (TPA)catalytic polymerization processbiodegradable polymersubstitute for non-biodegradable polyacrylic acid (PAC)
Donlar Corporation
OH
OHNH2
O
O
catalystheat N
O
O
n
hydrolysis
OHO
O
OH
H
NH
H
OO
NHn m
Principle 7
A raw material of feedstock should be renewable rather
than depleting wherever technically and
economically practicable.
Adipic Acid Synthesis
Contributes 2% anthropogenic N2O/year
Ni-Al2O3
370-800 psi Co / O2
120-140 psi
O
+OH
Cu / NH4VO3
HNO3 HO2CCO2H + N2O
Adipic Acid SynthesisRecycles nitrous oxide into adipic acid
synthesis new pathway to phenol
Solutia, Inc.
3 H2 O2
O
+OH
HNO3
HO2CCO2H + N2O
OH
2 H2
Adipic Acid SynthesisNo nitrous oxide generatedRenewable feedstock replaces petroleum-
based feedstockDraths and Frost, Michigan State
O
OH
OH
OH
OH
OH
E. coli
D-glucose
OH
OH
CO2H
O
3-dehydroshikimate
E. coli
HO2C
CO2H
cis, cis-muconic acid
Pt / H2
50 psi HO2CCO2H
Principle 7: Renewable feedstocks
Conversion of waste biomass to levulinic acid paper mill sludge, municipal solid waste,
unrecyclable waste paper, agricultural residuesBiofine,
Incorporated
OH
O
O
levulinic acid
OO
OO
OH
O
OH
O
O
NH2
OHOH
O
O
C CH2CH2CO2HCH3
OH
OH
-butyrolactone
methyltetrahydrofuran tetrahydrofuran
acrylic acid
-amino levulinic acid
diphenolic acid
succinic acid
Principle 7: Renewable feedstocks
CO2 feedstock in polycarbonate synthesis Improved Zn catalyst yields faster reaction,
uses milder reaction conditionsCoates et al., Cornell University
O
+ CO2
500 C, 100 psi CO2
catalyst
O*
O *
O
n
N NZn
OAc
iPr
iPr
Pri
Pri
catalyst =
Principle 8
Unnecessary derivatization (blocking group,
protection/deprotection, temporary modification of
physical/chemical processes) should be
avoided whenever possible.
Boric Acid-Mediated Amidation
Direct amidation of carboxylic acids with amines Boric acid: nontoxic, safe, inexpensive Eliminates use of SOCl2, PCl3, phosgene Widely applicable Emisphere Technologies, Inc
R OH
O
H N
R'
R''R N
O
R'
R''
H2O+cat B(OH)3toluenereflux
+
Principle 8: Derivatization
Enzymatic synthesis of cephalexin eliminates protection/deprotection of functional
groups
H N
O
ONaO
OMe
Me2NCH2C6H5
DMF -40 0C CH3CO2Cl
S
N
COOR
NH2
O
HH
Et3N-40 0C
Zn/HCl Et3Nsemicarbazide-HCl
O
N
N
S
COOH
H
O
HNH2H H
Cephalexin
S
N
NH2
O
HH
COOH
+O
OMe
NH2H
Penicillin Acylase pH 6.5
Altus Biologics
Principle 9
Catalytic reagents (as selective as possible) are superior to stoichiometric
reagents.
Principle 9: Catalysis
Improved synthesis of a central nervous system compound interdisciplinary approach, combining
chemistry, microbiology, and engineeringFor every 100 kg product,
300 kg chromium waste eliminated34,000 liters solvent eliminated
Eli Lilly and Company
Principle 9: Catalysis
O
O
CH3
O
Z. rouxii, XAD-7 resin O
O
CH3
OH
p-NO2PhCHO HCl
O
OO
CH3
NO2
air, NaOH, DMSO
O
OO
CH3
NO2
OH
O
O
CH3
O2N
NNH CH3
OOH
H2NNHAc
MsCl, Et3N
O
O
CH3
O2N
NNH CH3
OOMs 1. NaOH, EtOH2. KO2CH, Pd/C
N
NO
O CH3
O
NH2
CH3H
Principle 9: Catalysis
Synthesis of disodium iminodiacetate (DSIDA) filter catalyst from waste stream, no additional
purification requiredReplacement for the Strecker process
utilized NH3, CH2O, HCN, HClMonsanto
Company
NOH OH
H
Cu catalyst NNaO ONa
O OH
DSIDA
+ 2 NaOHH2O /
+ 4 H2
Principle 10
Chemical products should be designed so that at the
end of their function they do not persist in the
environment and break down into innocuous degradation products.
Polylactic Acid
Manufactured from renewable resourcesCorn or wheat; agricultural waste in future
Uses 20-50% fewer fossil fuels than conventional plastics
PLA products can be recycled or composted
Cargill Dow
Alternative solvents
Solvent-free synthesis of polylactic acid polymers (PLA) lactic acid obtained from corn and sugar beets condensation of aqueous lactic acid yields PLA
pre-polymer pre-polymer thermally depolymerized into L- and
meso-lactide diastereomers tin-catalyzed ring opening polymerization of lactide
produces PLA high polymerCargill Dow Polymers LLC
Alternative products
Eastman Biodegradable Copolyester 14766 copolyester of adipic acid, terephthalic acid, and
1,4-butanediol totally biodegrades to H2O, CO2, biomass reduces waste sent to landfills and incinerators
Eastman Chemical Company
Principle 11
Analytical methodologies need to be further
developed to allow for real-time, in-process monitoring
and control prior to the formation of hazardous
substances.
Principle 11: Real Time Analysis
1999: 10 million environmental samples analyzed
Analysis in support of state and federal regulatory programs used more than 2 million gallons of solvent
Spent waste solvent disposal cost is about $51 million
Principle 11: Real Time Analysis
Ion Fingerprint Detection (IFD) softwareMS peak deconvolution algorithmsRapidly identifies and quantifies EPA
targeted compounds by GC/MSSample cleanup not required in the
presence of other targets and contamination
90% solvent reduction for GC/MS analysis
50% solvent elimination for LC/MS analysis
10-fold productivity gains Robbat, Jr.
Principle 12
Substances and the form of a substance used in a chemical process should be chosen so
as to minimize the potential for chemical accidents, including
releases, explosions, and fires.
Principle 12: Minimize hazard
Simmons, in Green Chemistry: Designing Chemistry for the Environment
nitrilhydratase
N
OCN
CN1. H2SO4
2. NH3
NH2
O
+ (NH4+)2SO4
2-+ H2O
Biocatalysis: Synthesis of Acrylamide
Conventional Synthesis: Utilizes Corrosive Acid and Ammonia
Principle 12: Minimize hazard
Catalytically synthesize methylisocyanate to reduce risk of exposure eliminates use of phosgene
Manzer, DuPont
Old Synthesis of Methylisocyanate
New Synthesis of Methylisocyanate
CH3NH2 + COCl2 CH3NCO + HCl
CH3NH2 + CO CH3NHCHOcatalyst
CH3NHCHO + O2catalyst
CH3NCO
Green Chemistry
Not a solution to all environmental problems.
The most fundamental approach to preventing pollution.
Recognizes the importance of incremental improvements.
2004 Green Chemistry Events
227th ACS Meeting, March 2004, AnaheimJoe Breen Student Poster SessionInnovations in Green Chemistry Education
8th Annual Green Chemistry and Engineering ConferenceJune 29 – July 1, Washington, DC
Gordon Research Conference on Green ChemistryJuly 4-9, Bristol, RI
PRF Summer School on Green Chemistry
Student Affiliates
Host a green chemistry speakerDevelop a green chemistry activity with a local
schoolOrganize a green chemistry poster session on
campusWork with a local company on a green
chemistry projectMake a current lab experiment greenerDesign a green chemistry web page
Student Affiliates
BenefitsRecognition at the Student Affiliates
Chapter awards ceremony at the spring ACS meeting
Information on green chemistry internships and research opportunities
Copies of green chemistry materialsConnections to faculty engaged in green
chemistry research
Green Chemistry InstituteWorking Today to Prevent Pollution
Tomorrow Through Information DisseminationChemical EducationAwards and RecognitionConferences and SymposiaResearch and FellowshipsInternational Outreach
The Major Challenges to Sustainability
Population Energy Global Change Resource Depletion Food Supply Toxics in the Environment
Population Energy Global Change Resource Depletion Food Supply Toxics in the Environment
Population
Empirical data shows that increased quality of life correlates with sustainable population control.
Increased quality of life, however, has historically resulted in increased damage to the biosphere and the earth’s ability to sustain life.
Population
The challenge: How to increase quality of life while minimizing detrimental effects to human health, the environment and the biosphere.
The solution: Green chemistry provides a mechanism to addressing this challenge in very real terms.
Energy
The vast majority of the energy generated in the world today is from non-renewable sources that damage the environment.Carbon dioxide Depletion Effects of mining, drilling, etc Toxics
Energy
Green Chemistry will be essential in developing the alternatives for energy
generation (photovoltaics, hydrogen, fuel cells, biobased fuels, etc.) as well as
continuing the path toward energy efficiency with catalysis and product design at the forefront.
Global Change
Concerns for climate change, oceanic temperature, stratospheric chemistry and global distillation can be addressed through the development and implementation of green chemistry technologies.
Alternative Solvents/Reaction Conditions Award
CO2 blowing agent for manufacture of polystyrene foam sheet packagingeliminates 3.5 million pounds/year of
chlorofluorocarbon blowing agentscarbon dioxide obtained from existing by-
product commercial and natural sources, no net increase in global CO2
The Dow Chemical Company
Resource Depletion
Due to the over utilization of non-renewable resources, natural resources are being depleted at an unsustainable rate.
Fossil fuels are a central issue.
Resource DepletionRenewable resources can be made
increasingly viable technologically and economically through green chemistry. Biomass Nanoscience & technology Solar Carbon dioxide Chitin Waste utilization
Food Supply
While current food levels are sufficient, distribution is inadequate
Agricultural methods are unsustainable Future food production intensity is
needed. Green chemistry can address many
food supply issues
Food Supply
Green chemistry is developing: Pesticides which only affect target
organisms and degrade to innocuous by-products.
Fertilizers and fertilizer adjuvants that are designed to minimize usage while maximizing effectiveness.
Methods of using agricultural wastes for beneficial and profitable uses.
Toxics in the environment
Substances that are toxic to humans, the biosphere and all that sustains it, are currently still being released at a cost of life, health and sustainability.
One of green chemistry’s greatest strengths is the ability to design for reduced hazard.