Electrochemically-Mediated Separations for CO Capture

Electrochemically-Mediated Separations

for CO2 Capture

Fritz Simeon, Mike Stern, Howard Herzog and T. Alan Hatton

Department of Chemical Engineering and the MIT Energy Initiative (MITei) Massachusetts Institute of Technology Cambridge, MA 02139, USA

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CarbonCarbon CCaptureapture aandnd MMitigationitigation

Coal to play a major role in world’s energy future: lowest-cost for base-load electricity generation coal resources distributed around the world. Adverse environmental effects accompany its mining, transport and utilizations. Carbon Capture and Storage (CCS mitigate contribution of carbon-based fuel emissions to climate change,

capture carbon dioxide (CO2) from point sources, e.g., power plants and other industrial facilities, and store it in deep subsurface geological formations for indefinite isolation from the atmosphere.

World Primary Energy Consumption, World Electricity Generation by Fuel, 2005-2025 2005-2030 Petawatt-hours (1015 watt-hours) Trillion Kilowatt-hours

Sources:Sources: 2002005:5: EneEnergyrgy Information Information AdAdministrationministration (EIA),(EIA) InternationalInternationalEner Energygy Annual Annual 2005 2005 (June-(June Sources: 2005: Energy Information Administration (EIA), International Energy Outlook 2005, website October 2007), website www.eia.doe.gov/iea. Projections: EIA, System for the Analysis of Global www.eia.doe.gov/iea. Energy Markets/Global Electricity Module (2006). http://www.tobacco-facts.net/2009/12/coal-will-be-harder-to-quit-than-tobacco

Page | 2 CoalCoal CCombustionombustion CCaptureapture TTechnologyechnology

Post-combustion Challenges:

Dilute CO2 concentration in flue gas. Pre-combustion Challenges: Other flue gas components. Low operational temperature of existing CO2 removal technology. N2, O2 High capital and operational costs. More economical to combust syngas before fully shift (reducing fraction of CO2 captured). CO2 Flue Gas COC 2 Capture Unit Air Post-Combustion PowerP & Heat CO2 Pre-Combustion

CO2 Reformer & H2 Compression/ CO Separator PowerP & Heat Sequestration 2 DehydrationDehydra Air PowerP r & Heat CO2 Coal O Oxy-Combustion 2 Oxy-combustion Challenges: AirA Separation N Expensive cryogenic air separation. Air 2 High operational temperature of pure oxy Unit combustion requires new materials for boiler.

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Gas Separation Technology for Post-Combustion CCS

Alkanolamines, Blended alkanolamines Zeolites Gas/liquid contractors Piperazine, Amino acids Carbon Permselective membranes Second generation amine Silica High-temperature polymeric Third generation sorbent, Alumina Potassium carbonate, Chilled ammonia Absorptionorp Membranee AdsorptionA

Flue Gas R&D Pathways

EExploratoryx Biologicalcal Reactivetive Solid Adsorption

Algae Metal Oxides Metal Organic Frameworks

(photosynthesis) Sodium Bicarbonate CO2 Hydrates Carbonic anhydrase Sodium Hydroxide Liquid crystals

(enzyme-catalyzed CO2 capture) Lithium Zirconate Ionic Liquids Lithium Silicate

Thermal-Swing Processes

Energy for Separation

Pressure-Swing ProcessesIsothermal Processes Electrochemical-Swing Processes

Page | 4 Gas Separation Technology for Post-Combustion CCS

Excellent CO2 selectivity over N2 Increase CO2 permeation rates Reduce capital & operational costs Increase CO2/N2 selectivity Lower energy consumed Increase selectivity Increase CO2 capacity Improve economies of scale Minimize oxidative degradation Minimize Sox & Nox degradations Absorptionorp Membranee AdsorptionA

Flue Gas R&D Pathways

EExploratoryx Biologicalcal Reactivetive Solid Adsorption

Challenge in economies of scale Required highly porous materials Increase CO2 capacity Long term biological activity/stability Improve long term stability Improve CO2 selectivity Improve long term performance

Thermal-Swing Processes

Energy for Separation

Pressure-Swing Processes Isothermal Processes Electrochemical-Swing Processes

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ObjectiveObjective ofof CCSCCS RR&D&D ooff DDOEOE iinn TThehe UUnitednited ofof SStatestates

“Energy Cost + Retrofitting Cost”

Minimum CO2 capture = 90% Maximum increase in COE = 35% “Capital Cost + Operational Cost” + “Capital Cost

DOE/NETL-2009/1366 – Existing Plants, Emissions and Capture – Setting CO2 Program Goals CCS technology requires new approaches to achieve target of 35% maximum increase in COE.

Page | 6 TraditionalTraditional WWet-Scrubbinget-Scrubbing ProcessProcess

With extensive energy integration,

The theoretical minimum work is 0.11 MWh/ton CO2

Rochelle, G. T., Science 2009, 325:1652-1654

Developed over 70 years ago as non-selective acid gas removal processes Today, the only real option for deploying CCS technology Recent solvent R&D focuses on solvent degradation and equipment corrosion Need significant improvement to meet 35% maximum increase in COE

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PotentialPotential BenefitBenefit ofof EElectrochemical-Swinglectrochemical-Swing ProcessesProcesses

Significant decrease in total energy consumption for CCS Ease of integration with existing power plants Decrease in indirect cost of CCS Applicable to other large-scale carbon emitters with no possibility for energy integration for thermal swing processes Cement and chemical industries

Page | 8 ElectrochemicalElectrochemical SeparationSeparation ProcessesProcesses

Advantages of electrochemical processes in waste treatment industry: Versatile Energy efficient Lower temperature requirements Cell optimization to minimize power losses caused by overpotential and side reactions Cost effective

Electrochemical-Swing Gas Separation Technologies

Electrochemical Reaction Electrochemical Reaction of Target Molecules of Carrier Molecules Mode 1 Mode 2 Ox ne Red Red Ox ne Ox ne Reded RedRe Ox ne A Red A Red A-RedA - A Red

Oxx Red Ox A A-Red A influx outflux influx outflux

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Electrochemical Separation Processes

1970 – Electrochemical pumping of NO through thin films (Mode 2)

1974 – Molten carbonate electrochemical CO2 concentrator (Mode 1)

1979 – Aqueous carbonate electrochemical CO2 concentrator (Mode 2)

1981 – Flue gas desulfurization using an electrochemical SO2 concentrator (Mode 1)

1984 – Electrochemical removal and concentration of H2S from coal gas (Mode 1)

Electrochemical heterocyclic nitrogen compound separation – 1993 (Mode 2) Electrochemically-modulated complexation: CO concentrator – 1995 (Mode 2) Electrochemically-modulated complexation: ethylene/ethane separator – 1997 (Mode 2)

Electrochemically-modulated complexation: CO2 air capture – 2003 (Mode 2)

Separation of CO2 from flue gas using electrochemical cells – 2010 (Mode 2)

Page | 10 ElectrochemicalElectrochemical SwingSwing GasGas SeparationSeparation ProcessesProcesses

Electrochemical-Swing Gas Separation Technologies

Electrochemical Reaction Electrochemical Reaction of Target Molecules of Carrier Molecules Mode 1 Mode 2

Ox ne Reded RedRe Ox ne

Oxx Red Ox A A-Red A influx outflux influx outflux

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Electrochemical Gas Separation of CO2

Molten Carbonate Electrochemical Cell (1974) Winnick, J. et al., AIChE Journal 1982, 28(1):103-111

Considered for CO2 removal in a manned spacecraft Electrochemical reactions: 2- Cathodic reaction: CO2 + ½O2 + 2e = CO3 2- Anodic reaction: CO3 = CO2 + ½O2 + 2e High temperature operation ~ 700°C

60% CO2 removal efficiency

CO2 removal efficiency increases with increasing current density Current efficiency decreases with increasing applied current density (still remaining challenge)

H2 H H2O 2 CO2 + H2 CO + H2O CO2-AIR CO2-AIR 2- CO 2- CO3 CO2 + ½O2 + 2e CO2 + ½O2 + 2e CO3 CO2 Porous Porous Electrodes Electrodes 2- 2- CO2 + ½O2 + 2e CO3 CO3 CO2 + ½O2 + 2e N2 CO2-AIR CO2-AIR N2 CO2

Molten Carbonate Fuel Cell Molten Carbonate CO2 Separation Cell (Hydrogen Mode) (Driven/Nitrogen Mode)

Page | 12 Electrochemical Gas Separation

FGD using electrochemical SO2 concentrator (1981) Townley, D. and Winnick, J. Ind. Eng. Chem. Process. Des. Dev. 1981, 20(3):435-440 Electrochemical reactions: “Driven” mode: 2- Cathode: SO2 + O2 + 2e = SO4 2- Anode: SO4 = SO3 + ½O2 + 2e “Reducing-gas” mode: 2- Cathode: SO2 + O2 + 2e = SO4 2- Anode: SO4 + 5H2 = 4H2O + H2S+ 2e

Cell configuration for electrochemical SO2 concentrator

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Electrochemical Gas Separation

Concentrate SO2 from 0.03% at the cathode to 10% at the anode at 600°C. Operational energy costs: For a 500 MWe plant burning 3.5% sulfur coal of 9000 Btu lb heating value, the total electrical energy required is about 2% of the plant power, comparing to other FGD processes requiring up to 6% of plant power. Operating costs: ~ 0.05 cents/kWh in the driven mode and ~ 0.15 cents/kWh in the reducing-gas mode (wet scrubbing processes cost 0.14 to 0.20 cents/kWh). Experimental result:

Nearly all SO2 was scrubbed from the flue gas, with less than 5 ppm remained.

Page | 14 Electrochemical Gas Separation

Electrochemical removal of H2S from coal gas (1984) Electrochemical reactions: Current Sources 2– Cathode: H2S + 2e = H2 + S Sweep N2 H2S 2– S Vapor Anode: S = ½ S2 + 2e Contaminate 2 d Fuel Gas

Feasible H S removal at high temperature S2 2 H2 S 98% removal efficiency of H2S with Polished Fuel Gas H Sweep reasonable levels of polarization 2 N2 Favorable capital and operational costs Porous Electrolyte Porous for the H2S concentrator Cathode Membrane Anode Current Efficiency Removal Efficiency

Current Density (mA/cm2) Current Density (mA/cm2) Removal efficiency as a function of current density Current efficiency as a function of current density at 840°C

Lim, H. S. and Winnick, J. J. Electrochem. Soc. 1984, 131(3):562-568 and 65% H2S cathode inlet

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ElectrochemicalElectrochemical SwingSwing GasGas SeparationSeparation ProcessesProcesses

Electrochemical-Swing Gas Separation Technologies

Electrochemical Reaction Electrochemical Reaction of Target Molecules of Carrier Molecules

Electrochemical Facilitated Transport Processes Equilibrium Stage Processes

Receiving Carrier Stream Regenerationn Step 4: Electrochemical Solute ElectrodeEl t d Activation Target Stripping Recovery Target Step 1: Capture Increase Carrier Step 3: Electrochemical Affinity Decrease Deactivation Carrier Affinity Electroded

Step 2: Electrode Electrode Solute Feed Feed Receiving Extraction Stream Stream Stream

Page | 16 Electrochemical Gas Separation

Electrically Induced Carrier Transport (1970) Ward, W. J. Nature 1970, 227:162-163 (Electrochemical Facilitated Transport Processes) Redox carrier, ferrous chloride, facilitates electrochemical pumping of nitric oxide (NO) through thin films creating a pressure difference in the NO

Cathodic reaction: 3 2 Fe e Fe Anodic reaction: NO Fe2 FeNO2 FeNO 2 NO Fe3 e Liquid Film

Concentration profile Concentration profiles which are established in a liquid film across due to passage of current through the film NO NO FeNO2+ influx outflux

Induced transport of nitric oxide as a function of current density

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Electrochemical Gas Separation of CO2

Electrochemically-Regenerable CO2 Absorber (1979) (Electrochemical Facilitated Transport Processes) Life System, Inc. 1973, Electrochemical CO2 Concentrator 2– – Overall reactions: CO3 + H2O + Electrical Energy = 2OH + CO2 + Heat External Gas Manifold

Cathode Anode

H2 2H2O 2– H2 CO3

– 2OH CO2 H2O 2– + CO3 Process Process Gas Inlet CO2 Gas Outlet

2 2H2O 2e 2OH H2 CO3 H2 H2O CO2 2e

Separation of CO2 from flue gas using electrochemical cells (2010) Electrochemical reactions: Pennline, H.W. et al Fuel 2010, 89:1307-1314 – Cathode reaction: O2 + 2H2O + 4e = 4OH – Anode reaction: 4OH = O2 + 2H2O + 4e

Page | 18 Equilibrium Staged Electrochemical Separations

Requirements for redox active carriers: Carrier soluble only in contacting phase Carrier with target binding site and ability to undergo chemically reversible redox cycle in presence and absence of target molecule Considerable differences in the affinity of carrier for target molecule in different oxidation states Rapid kinetics of complexation reaction Applications:

Heterocyclic nitrogen compound separation (1993)Jemaa, N. et al. AIChE Journal 1993, 39(5):867-875 Fe(II) and Fe(III) electrochemical cycling Continuous electrochemically-modulated complexation separation process

Carbon monoxide separation (1995) Terry, P. A. et al. AIChE Journal 1995, 41(12):2556- 2564 Cu(I) and Cu(II) electrochemical cycling

Terry, P.A. et al. AIChE Journal 1997, 43(7):1709- Ethylene/Ethane separation (1997) 1716 Cu(I) and Cu(II) electrochemical cycling

Scovazzo, P. et al. J. Electrochem. Soc. 2003, 150(5):D91- Air capture of carbon dioxide (2003) D98 2,6-di-tert-butyl-1,4-benzoquinone electrochemical cycling

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ElectrochemicalElectrochemical SeparationSeparation ProcessesProcesses

Potential-swing induces dramatic change in effective binding constant of carrier (C) toward target molecule (L)

Ability to control binding constant (Kbinding) Can approach thermodynamically-reversible separation with potential- swing processes

10000

* 1000 C ne C 100 C* L C*L 10 E E o

o 1 Kbinding E E Kbinding E -0.30 -0.20 -0.10 0.00 0.10 0.20 0.30 nF 0.1 E exp E o E RTR 0.01

0.001 [C L] 1 K Eo 0.1 to 100 M binding [ ][ ] 0.0001 C L

Page | 20 Ideal Work for Electrochemical Separation

Cleaned Flue Gas

CO2 Rich Flue gas Separation Unit Carbon Dioxide

Electrical Work Reaction during absorption process: C e C * C * CO C * CO 2 2 Reaction during desorption process:

C * COCO2 CCOC CO2 e

CCOC CO2 C CO2

Electrical energy required per mole of CO2 separated:

Welectrical F E

E E E cathode anode

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Minimum Work of Electrochemical Separation

RT redre RT C * Nernst Equation: E Eo ln Eo ln nF oxo F C

C * CCO2 Equilibrium of C* with CO2: Kbinding C * COC 2

nCO2 ,o nCO2 ,t Extent of reaction with respect to CO2: nCO2 ,o

Electrical energy required per mole of CO2 separated:

* * Cred C C COC 2

C T C Cred RT C E E o ln redre F 1 C T Cred Kbinding COC 2 1

Ecathode Ecaptured 0 1

Eanode Eregenerationd 0

Page | 22 Minimum Work of Electrochemical Separation

EquilibriumEquilibrium StageStage ProcessesProcesses ElectrochemicalElectrochemical FFaciacililitatedtated TransportTransport PrProcessesocesses (FOUR-STAGE(FOUR-STAGE PRPROCESSES)OCESSES) (TWO-STAGE(TWO-STAGE PROCESSES)PROCESSES)

ReceivingReceiving StreamStream CarrierCarrier RegenerationRegeneration StepStep 44:: SoluteSolute ElectrochemicalElelectrochemiccaala ElectrodeElecttdrode StrippingStripping ActivationActivation TargetTarget RegenerationRegeneration Step 1: TargetTararget IncreaseIncrease CaptureCapture CCarrierarrier Step 3: AffinityAffinity DecreaseDecD rease ElectrochemicalElelectrochemiccaala CCarrierarrier DeactivationDeactivatiooon AffinityAffinity Electroded

Step 2: ElectrodeElectrode El Electrodeectrode SoluteSolute FeedFeed FeedFeed Receivingeceivin ExtractionExtraction StreamStream StrStreameam StrStreameam

P , Four-Stage Processes: ln CO2 regeneration Welectrical RT Kbinding (Electrochemical Separation) Vm HCO2

1 xo Two-Stage Processes: W RT lnl xo CO2 ln1 xo electrical CO2 xo CO2 (Electrochemical Separation) CO2

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Minimum Work for Electrochemical Separation

LOG(Kbinding) )

2 3 8 13 18

100000 Four Stage Process P , ln CO2 regeneration Welectrical RT Kbinding Vm HCO2

Final CO Partial Pressure = 1 atm 10000 2 CO2 solubility = 0.129 mol/L atm eparation (J per mole of CO

1000 1 xo W RT lln xo CO2 ln 1 xo electrical CO2 o CO2 Two Stage Process xCO2

Welectrical WCO separation 100 2 Minimum work Minimum work for s 0.1 0.3 0.5 0.7 0.9

CO2 partial pressure at the inlet stream (atm)

Page | 24 Minimum Work for Electrochemical Separation

LOG(Kbinding) )

2 3 8 13 18

100000 Four Stage Process P , ln CO2 regeneration Welectrical RT Kbinding Vm HCO2 Final CO Partial Pressure = 1 atm 2 o CO solubility = 0.129 1mol/Lx atm 10000 2 lln o CO2 ln 1 o Welectrical RT xCO2 o xCO2 xCO2

Welectrical WCO2 separation eparation (J per mole of CO

1000

Two Stage Process

100 Minimum work Minimum work for s 0.1 0.3 0.5 0.7 0.9

CO2 partial pressure at the inlet stream (atm)

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Two Stage Electrochemical Separation Process

Cleaned Stack Gas

Electrode Electrode Gas Phase Sorbent Phase Sorbent Phase Gas Phase C C Carrier Regeneration Electrochemical Activation CO2 C* Regeneration CO2 Capture C

Electrochemical Deactivation

C* C*

Absorption Process Desorption Process

CO2 Rich Flue Gas Pure CO2 Stream

CO2 capture and regeneration processes mediated by simultaneous activation and deactivation of redox carriers through electrochemical processes.

Page | 26 RedoxRedox CCarrierarrier fforor COCO2 CaptureCapture

Metal Organic Carrier CO2 2e–

regenerationon reductionred

Cu(II) complexes1 Ni(II) complexes2

Organic Carriers QUINONE

2,6-di-tert-butyl-1,4-benzoquinone3

Acid-base reaction of dianionic quinones with CO2 - electron rich oxygens donate and share electron pairs with electrophilic – 2e oxidation capture CO2 carbon of CO2 molecules to form stable carbonates

1Appel, A.M. .et al. Inorganic Chemistry 2005, 44(9):3046-3056 High Electron Density Low Electron Density 2Newell, R. et al. Inorganic Chemistry 2005, 44(2):365-373 3Scovazzo, P. et al. J. Electrochem. Soc. 2003, 150(5):D91-D98

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ElectrochemistryElectrochemistry – CyclicCyclic VoltammetryVoltammetry TechniqueTechnique

Study electrochemistry of carrier by monitoring electron flowing 10 Oxidation 0.8 from the electrode (reduction) and to the electrode (oxidation). 8 0.7

Electrode Reduction 6 0.6 e Fermi Level 4 0.5 Lowest Unoccupied Molecular Orbital A) ( 2 0.4

0 0.3 Current ( Potential (V) Potential Oxidized Carrier -1 4 9 14 Molecular Orbital -2 Time (s) 0.2

-4 0.1

Electrode Oxidation -6 Reduction 0

e Highest Occupied Molecular Orbital 10 Fermi Level Oxidation 8 6 Reduced Carrier 4 Molecular Orbital A) ( 2 Potential (V) 0

Current ( -2 0 0.2 0.4 0.6 0.8 -4 -6 Reduction

Page | 28 ElectrochemistryElectrochemistry ooff 22,6-dichloro-quinone,6-dichloro-quinone ((BQ-Cl2)BQ-Cl2)

Potential (V) Potential (V)

0 -0.5 -1 -1.5 -2 -2.5 0 -0.5 -1 -1.5 -2 -2.5 10 10

under Nitrogen under Carbon Dioxide

0 0

-10 -10

BQ-Cl2 A) -20-2 A) --20 ( ( Current ( -30 Current ( -30

-40 -40 -0.85 V st -0.85 V 1 electron transfer 1st electron transfer -50 -1.66 V -50 -1.44 V 2nd electron transfer 2nd electron transfer

CO2 stabilizes the dianion quinone -60 -60

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ElectrochemistryElectrochemistry ooff 22,6-dichloro-quinone,6-dichloro-quinone ((BQ-Cl2)BQ-Cl2)

Potential (V) Potential (V)

0 -0.5 -1 -1.5 -2 -2.5 0 -0.5 -1 -1.5 -2 -2.5 10 10

under Nitrogen under Carbon Dioxide

0 0

-10 -10

BQ-Cl2 A) -20-2 A) --20 ( ( Current ( -30 Current ( -30

-40 -40 -0.85 V st -0.85 V 1 electron transfer 1st electron transfer -50 -1.66 V -50 -1.44 V 2nd electron transfer 2nd electron transfer

CO2 stabilizes the dianion quinone -60 -60

Page | 30 ElectrochemistryElectrochemistry ooff 22,6-ditert-butyl-quinone,6-ditert-butyl-quinone ((BQ-TB)BQ-TB)

Potential (V) Potential (V) 0 -0.5 -1 -1.5 -2 -2.5 0 -0.5 -1 -1.5 -2 -2.5 10 10

under Nitrogen under Carbon Dioxide

0 0

-10 -10

BQ-TB A)

A) -20-

--202 ( ( Current (

Current ( -30 -30 -1.19 V 1st electron transfer -2.08 V -40 -40 2nd electron transfer

-50 -50 -1.12 V

Two single electron transfer of BQ-TB under N2 One double electron transfer of BQ-TB under CO2 -60 -60

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ElectrochemicalElectrochemical ReactionReaction wwithith StackStack GasGas ComponentsComponents

From The Future of Coal, MIT, 2007, page 115

Page | 32 ElectrochemicalElectrochemical ReactionReaction wwithith StackStack GasGas ComponentsComponents

Potential (V) -2 -1.5 -1 -0.5 0 40 Chemical reaction between •– Oxidation superoxide anion radical (O2 ) and 1 CO2. Reversible 20 electrochemistry – 2– O2 + 2CO2 + 2e → C2O6

0 indicated by disappearance of oxidation peak of superoxide anion •– radical (O2 ) in the presence of -20 CO2. Current (mA) -40 -1.3 V is the maximum cathodic potential limit for ideal redox carrier Reduction o E oxygen = -1.3V -60

Oxygen Oxygen and Carbon Dioxide -80

1Wadhawan J.D. et al. J. Phys. Chem. B 2001, 105, 10659-10668

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InductiveInductive EffectEffect ofof SideSide FFunctionalunctional GGroupsroups

Inductive effect - transmission of charge through a chain of atoms by electrostatic induction.

NO2 > F > COOH > Cl > Br > I > OH > OR > C6H5 > H > Me3C- > Me2CH- > MeCH2-> CH3

Electron-withdrawing Electron-donating

BQ BQ-TB BQ BQ-TB BQ-Cl4 BQ-Cl2

BQ-Cl4 NQ BQ-Cl2NQ NQ-Cl2 NQ-Cl2 AQ PQ under nitrogen Reduction of O2 under carbon dioxide AQ PQ

Page | 34 CyclicCyclic VoltammogramsVoltammograms ofof QuinoidalQuinoidal RedoxRedox CarriersCarriers

10 Internal Standard Oxidation BQ 5 Irreversible electrochemistry A) 0 Cathodic potential > -1.3V ( -2.2 -1.4 -0.6 0.2 -5 (NOT IDEAL CARRIER)

Current ( -10

-15 Reduction -20 Potential (V) -25

Oxidation 10

Reversible electrochemistry 5 Internal Standard AQ

A) Cathodic potential < -1.3V ( 0 (NOT IDEAL CARRIER) -2.2 -1.4 -0.6 0.2 -5 Current (

-10 Reduction Ideal redox carrier must have -15 Potential (V) “Nernstian” reversible electrochemistry -20 in the presence and absence of CO2

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Molecularly-OptimizedMolecularly-Optimized RedoxRedox CarrierCarrier forfor COCO2 CaptureCapture

o 15 E oxygen = -1.3V 0.00 CO2 0.10 CO2 oxidation 0.20 CO2 10 0.40 CO2 0.60 CO2 Internal standard 5 0.80 CO2 1.00 CO2 A)

( Reversible electrochemistry 0 Cathodic potential > -1.3V -2.2 -1.7 -1.2 -0.7 -0.2 0.3 (IDEAL CARRIER)

Current ( -5

Under N2 -10 (0.00 CO2) Increase CO2 partial pressure -15 reduction

Potential (V) -20

Page | 36 ConcludingConcluding RRemarksemarks

Electrochemical separations have a potential for long-term CO2 scrubbing applications Two-stage electrochemical separator is ideal system for energy efficient

CO2 capture processes

Future electrochemical CO2 separations: Molecular-engineered redox carrier molecule Understanding of electrochemical separation Advanced infrastructure materials

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COECOE ofof ECMSECMS ProcessesProcesses

“Energy Cost + Retrofitting Cost” 60 50% desorption efficiency 55 70% compression efficiency “Zero” Cost of Retrofitting to Existing Plant

50 Operational Cost” + “Capital Cost 45 Minimum lost 40 work due to CCS 35 Phase I

30 Process Development

25 New Existing ECMS PCP PPlantlant PCP Plant 20 Amine-Scrubbing Process Direct Costs of CCS 15 Phase II Phase Infeasible Material Development 10 Region Process Optimization 5

051015 20 25 30 35 40 45 50 55 60 Indirect Costs of CCS

Page | 38 AcknowledgementsAcknowledgements

Funding

Siemens Corporation As of today (assuming the contract will been signed), ARPA-E

Doing the Work

Fritz Simeon, Mike Stern and Howard Herzog

Page | 39