FromMembraneBiofoulingControltoAquaporinChannels
IsabelC.Escobar,PhDProfessorFPAT763D
ResearchfocusMy research focuses on developing and/or improving polymeric membrane materials through membrane materials development and post-synthesis modifications. Among my current projects are (1) low-fouling membranes; (2) anti-biofouling polypropylene feed spacers; (3) biofouling mechanisms; (4) low-fouling membranes using temperature-sensitive polymers activated using superparamagnetic iron nanoparticles; (5) polybenzoimidizole forward osmosis membranes; and (6) biomimetic membranes.
I have written over 50 manuscripts, have 1 licensed patent, and have over 100 presentations made at national and international conferences on membrane separations.
PhD in environmental engineering: Membrane separations
Chaired 3 membrane conferences AIChE Kunesh Award 2011 Board of Directors of NAMS
I am Associate Editor of EP&SE
With Professor Andrea Schaefer
Modern Applications inMembrane Science and
Technology
ACS SYMPOSIUM SERIES 1078
EDITED BYIsabel Escobar
and Bart Van der Bruggen
With Professor Bart Van der Bruggen
PointsofPrideI am Editor of the IDA Journal of Desalination & Water Reuse
Feed Permeate
Concentrate
¥ Allowformorechoicesoffeedwaters
• Sea/BrackishWaterDesalinaGon,LowQualitySurfaceWater,Wastewater
¥ Higherpuritywatercanbeproducedtomeetincreasesinstringencyofwaterqualitystandards
¥ LessfootprintthantradiGonalwatertreatmentplants
WhyMembranes?
Membrane Process Application Guide .001 .01 .1 1.0 10 100 1,000
DissolvedOrganics
SandBacteria
Viruses
Salts Colloids
* MediaFiltraDon(sizeexclusion)
MicrofiltraDon(sizeexclusion)
UltrafiltraDon(sizeexclusion)
NanofiltraDon(sizeanddiffusion)
ReverseOsmosis(sizeanddiffusion)
* MediafiltraDon(notamembraneprocess)isshownforreferenceonly.
m m m m m m m
€
µ
*Electrodialysisremovesonlyionicspecies
€
µ
€
µ
€
µ
€
µ
€
µ
€
µ
WhatisBiofouling?Biofoulingistheundesireddevelopmentofmicrobiallayersonthemembranesurfaceandthefeedspacer.Inbiofilms,organismssecreteextracellularpolymericsubstances(EPS),whichaidsintheiraUachmenttoasurfaceandresultsintheformaGonofamatrixofmicrobialorigin. Membrane Surface
MicrobialAUachment
MicrobialColonizaGon
EPS&MicrobialGrowth
0
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FluxDeclin
e(%
)
Time(hr)
FluxDeclinevs.FiltraDonTime
HausmanR.,andI.C.Escobar(2013).JournalofAppliedPolymerScience,128(3):1706-1714.
Low-BiofoulingMembranesv Copper as Biocide:
v Disinfects water against microbial biofilms with effective dosages of a few tenths of 1 mg/L [1].
v Thought to be cytotoxic by causing changes in the plasma membrane permeability [2].
v Generates reactive hydroxyl radicals, which can cause cellular damage imparted via oxidative stress [2].
v It coordinates with proteins through thiol groups causing inhibition of the protein’s biological activity.
v Silver is known biocide: v Known to have strong
interactions with thiol groups, such as sulfydryl and –SH [3].
v Silver attacks cytoplasmic proteins and DNA causing inactivation of enzymes [4].
v Silver nanoparticles were chosen instead of chelating silver ions [5].
1. Kim et al (2002) Water Research, 36: 4433-4444. 2. Selvaraj, S. et al. (2009) Journal of Hazardous Materials, 166(2-3): p. 1403-1409. 3. Belly, R.T., Kydd, G.C., Silver resistance in microorganisms. Dev. Ind. Microbiol., 1982. 23: p. 567-577. 4. Pradeep, T. and Anshup (2009) Thin Solid Films, 517(24): p. 6441-6478. 5. Hausman R., and I.C. Escobar (2013). Journal of Applied Polymer Science, 128(3): 1706-1714.
Low-BiofoulingPolypropyleneFeedSpacersResults
sample of cells taken from modified
and copper charged PP sheets
after 48hrs
sample of cells taken from virgin PP sheets after
48hrs
Acknowledgements NSF SGER 0714539 & CBET 0754387 Patent US-2011-0120936-A1
Biofouling after 48 hours with
modified spacer
Initial biofouling
with traditional
spacer
Biofouling after 48 hours with virgin spacer
Waterpermeability
Low-BiofoulingMembranesAfter IDA and copper treatment the membranes changed from white to blue.
Acknowledgements Department of Interior – USBR NSF OISE 1264103 USAID
AsapuS.,S.Pant,C.L.Gruden,andI.C.Escobar(2014),Desalina6on,338:17-25.AsapuS.,S.Pant,P.Majid,I.C.Escobar,andC.Gruden(inpress2015),JournalofWaterReuseandDesalina6on,doi:10.2166/wrd.2015.001
ResponsiveMembranes• SDmuli-responsive
polymers• Uniqueabilitytochangefroma
coiledtoglobularformaGoninthepresenceofasGmulus
• SimuluscanbepH,temperature,ionicstrength,electricalandmagneGcfields:
(a) NIPAAM hydrogel at room temperature (b) NIPAAM hydrogel at 34°C
(a) (b)
NIPAAMmembrane-coldcontactangle 47°
NIPAAMmembrane-hotcontactangle 56°Acknowledgements
NSF CBET 0610624 NSF GK-12 DGE-0742395
0.00#
1.00#
2.00#
3.00#
4.00#
5.00#
6.00#
7.00#
8.00#
0# 5# 10# 15# 20# 25# 30# 35# 40#
tempe
rature(adjus
ted(flu
x,(L/m
2hr(
time,(hr(
18%#CA+2%#NIPAAm#18%#CA#18%CA+2%NIPAAm4#average#flux##18%CA4#average#flux#
18%CA
18%CA+2%NIPAAm
SEMa=erfiltra6on
ChedeS.,andI.C.Escobar(2015).EnvironmentalProgress&SustainableEnergy,doi:10.1002/ep.12252.
ForAcDvaDon…• Attaching carboxylated PNIPAAm (PNIPAAm-COOH) to amine group-
attached iron oxide magnetic nanoparticles using carbodiimide (EDC) chemistry
S
NHO
n
OH
O
+EDS
NHS
PNIPAAm-COOH PNIPAAm-NP
NP NH2
S
NHO
n
N
O
H
NP
Membrane placed at the center of the coil for RF heating
Radio frequency (RF) heating was achieved by sending current through coil. In present studies, current of 250 A and frequency 173 kHz was carried through a copper coil:
BiomimeDc&Bio-inspiredMembranes
5/13/14
1
!"#$%&'()**+,%-#"./01"23%45%%
67"/#7/%+#(%8/7,#4*4$3% !&-68%
Emerging membrane materials: from self-assembled
to biomimetic membranes!
%&(.+#7/(%9/:'0+#/1%+#(%;404)1%9+2/0"+*1%</#2/0=%
</#2/0%540%>/1+*"#+?4#%+#(%@+2/0%A/)1/=%!&-68%%
Journal of Membrane Science 454(2014)359–381
5/13/14
3
Journal of Membrane Science 454(2014)359–381
Journal of Membrane Science 454(2014)359–381
5/13/14
5
9
Apr. 19, 2005 — CORVALLIS, Ore. - Researchers from the College of
Forestry at Oregon State University have developed a new group of
adhesives that may revolutionize a large portion of the wood products
industry, and have important environmental and economic benefits.
Li observed mussels being pounded by ocean waves, and wondered
how they could cling so tenaciously to rocks by their thread-like
tentacles.
"I was amazed at the ability of these small mollusks to attach
themselves so strongly to rocks," said Li, who is an expert in wood
chemistry and adhesives in the OSU Department of Wood Science
and Engineering. "Thinking about it, I didn't know of any other type
of adhesive that could work this well in water and withstand so much
force."
Mussel-Inspired Surface Chemistry for
Multifunctional Coatings Haeshin Lee, Shara M. Dellatore, William M. Miller, Phillip B. Messersmith
Science 2007, 318, 426-430
Source:Klaus-V.Peinemann,KAUST
MembraneswithAquaporinChannels
How Nature does membranes … and far exceeds man-made performance
General cell wall structureSodium specific pump
Proton pumpsAquaporin water purifier
Nature is:• Incredibly diverse• Precisely selective• Very fast. Protein channels ~ 10^7
molec/s compared to transporters 10^2 molec/s.
• Aquaporin is 10,000 times faster than Haggen-Poiseuille flow prediction.
Protein Channels Basics
T.M. Devlin ‘Textbook of Biochemistry 6th ed’
Schematic representations explaining the mechanisms for blocking proton permeation in aquaporin.
Acknowledgements NSF 1308095
• Combinetheultra-efficientfuncGoningofbiologicalmoleculeswiththeproducGvityofsyntheGcmembranes.
• Aquaporins–Waterchannelproteins
presentincellmembranestoregulatetheflowofwaterinandoutofthecellwhileprevenGngthepassageofionsandothersolutes.
• AddiGonofAqpZ;atypeofAquaporinsexpressedfromE.Coli,totheflatsheetpolymermembranestoimprovewaterfluxandrejecGonforwaterreuseanddesalinaGon.
MembraneswithAquaporinChannels• PureWaterPermeability:
PBImembranefluxanalysis:Recoveryof61% PVA-alkyl-AqpZfluxanalysis:Recovery88%
0"
2"
4"
6"
8"
10"
0" 20" 40" 60" 80" 100" 120" 140"
Flux,"LM
H"
Time,"hrs"
Precompac<on"BSA"Lipase"NaCl"3.4"mM"NaCl"10"mM"NaCl"20"mM"NaCl"35"mM"NaCl"100"mM"CaCl2"3.4"mM"
0"
2"
4"
6"
8"
10"
0" 50" 100"
Flux,"LM
H""
Time,"hrs"
Precompac=on"BSA"Lipase"NaCl"3.4"mM"NaCl"10"mM"NaCl"20"mM"NaCl"35"mM"NaCl"100"mM"
• SaltPermeability:
0"
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50"
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80"
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100"
0" 20" 40" 60" 80" 100" 120"
%"Rejec1o
n"
Feed"concentra1on"(mM)"
NaCl%filtra)on%rejec)on%Aqp"modified"membranes"unmodified"membranes"
0"
10"
20"
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50"
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0" 20" 40" 60" 80" 100" 120"
%"Rejec1o
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Feed"concentra1on"(mM)"
CaCl2%filtra)on%rejec)on%
Aqp"modified"membranes"Unmodifed"membranes"
Wagh,P.,G.Parungao,R.E.ViolaandI.C.Escobar(2015).Separa6onandPurifica6onTechnology,156(2):754-765.
Scaled Processing • Slot die extrusion - premetered casting • Producing films typically above 15 µm from
solution and 20 nm from a suspension
a.
b. Picture of two slot die halves bottom) is a top view of the internal cavity.
Roll-to-roll Processing System
Heating control panel
Heated tank
Brake power supply
Roll-feed computer
LabVIEW monitoring station
Motor Brake Web speed control
Inspection system Inspection computer
with MATLAB
Inspection monitor
Power and thermocouple connections
Heated slot die
Heated platen
Scale up studies
0
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perm
eabi
lity
time, hr
precompaction (lab scale) BSA filtration (lab scale)
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perm
eabi
lity
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precompaction (scale up)
lipase filtration (scale up)
BSA filtration
lipase filtration
BSA filtration
Lipase filtration
Lab scale 76.42% 68.06% Scale up 75.53% 78%
flux recovery after backwash
after BSA protein filtration followed by backwash
after lipase protein filtration followed by backwash
Lab scale Scale up
Acknowledgements NSF OISE 1264103 USAID
UsedforDifficultSeparaDons
HAB GROWTH
NUTRIENTS
GRAZING
WIND SPEED
WATER TEMPERATURE
LIGHT MICROCYSTIN PRODUCTION
Drinkingwater(provisional):1µg/LmicrocysGn-LR(WHO) 3µg/Lanatoxin-a(Australia)
TolerableDailyIntake(provisional):0.04µg/kg/day(WHO)
§ Highlywatersolubility§ StableinextremetemperaturesandpH§ NodegradaGonoftoxinaper15minutesofboiling
Drinking water treatment system
Flocculation
ParDculate(cell)removalParDculate(cell)removal
Dissolved(toxin)removal:NotcompletelyeffecDve
Dissolved(toxin)removal:HelpfulbutmaynotbeeffecDveenough
To distribution system and
consumer tap
Source water with cyanoHAB
Toledo plant intake 3 miles offshore
Finished water
water
Flocculation
Treatment Process Concentration of MC-LR (ppb)
Ozonation 0.00
Biofiltration >5.00
Ozonation and Biofiltration 0.00
Ozonation, Biofiltration and Ultrafiltration 0.083
Biofiltration and Ultrafiltration 0.917
Nanofiltration 0.421
Ultrafiltration 2.552
Results
1
Evenasmembranetechnologiesmature,newinnovaGonsarebeingintroduced.Althoughmostofthesechangesareincremental,theyconGnuetoimprovereliability,reducecost,andmiGgateenvironmentalimpacts.
Conclusions