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Nuclear Hydrogen Production Handbook Xing L. Yan, Ryutaro Hino

Water Electrolysis

Publication details https://www.routledgehandbooks.com/doi/10.1201/b10789-6 Seiji Kasahara Published online on: 28 Mar 2011

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The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The publisher shall not be liable for an loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Seiji Kasahara Water Electrolysis 3 n plmr lcrlt wtr lcrlss Te icsin s ae o rve o the of review on based is ­literature [3–6]. discussion The electrolysis. water electrolyte polymer and fossil-fuel reforming world ofsupplies the remainder the hydrogen now demand [2]. by produced hydrogen and contrast,economical made and developed been has gas, natural or methane In chiefly resources, high. remains electricity of cost the because mainly limited Norway.applicationsbeen has industrial in Its wideruse used is It oxygen.more often placesin whereand hydropowerhydrogen is abundantly produced,purity for example, high Iceland and of production the for preferred is method lyte designs. developed newly The date. ­electrolysis cells very include the high-pressure this designs and to state-of-the-art membrane continued electro have method the of performance cal developmenteconomi improve and the to[1]. research constructed were Industrial size 1920s century. the In 1930s, and of twentieth overthe in several plants 10 the beginning around operating were installations was Some 1890s. in electrolysis Waterpracticed energy. commercially already electric using molecules water of decomposition direct the by by-productoxygen, and hydrogen, producing of method a is water of Electrolysis 3.1 Nomenclature 3.4 3.3 3.2 3.1 C References © 2011 byTaylor and Francis Group, LLC ontents This chapter discusses electrolysis of liquid water, that is, alkaline water electrolysis water alkaline is, that water, liquid of electrolysis discusses chapter This ofwater Electrolysis percentagefewsupplies ofworlda only today.hydrogen used The

Introduction 3.4.3 3.4.2 3.4.1 Polymer Water Electrolyte Electrolysis 3.3.3 3.3.2 3.3.1 Water Electrolysis Alkaline Principle Introduction

...... Industrialization Development and Research Outline Industrialization Development and Research Outline ......

MWe 8 8 8 8 9 9 9 9 9 8 9 8 83 9 5 2 6 6 3 3 2 7 4 6 5 ­ - Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6

as the initial pressure. H pressure. initial the as requirement are fixed. In the case theofcase Infixed. water are requirement decomposition,therelation of heatand workis equation below. accordance the with in reaction of the balance entropy and enthalpy maintain to reaction a from taken workaddedand Heatto and are 3.2 84 G–T diagram of decomposition of water. of decomposition G–T diagram F below is temperature the when products obtain to needed workis input 3.1. Figure certain A in illustrated schematically

explained in Chapter 4 because the technology is different from electrolysis at ambient at electrolysis temperature. Here, applied methods electrolysis to water liquid is discussed. from are different is type technology This the because electrolysis. 4 Chapter steam in explained high-temperature called is 1000°C to hundred several demand Electricity electricity. as provided depends on temperature. The is is requirement atsmaller higher temperature. Electrolysis at requirement work the which of reaction a ofwork.as regarded be ofwater kind Electrolysis can certain a requires pressure initial the to gases these of pressure the Toloweratwaterdecompositiontemperature. increase by type. electrolyte different are tions © 2011 byTaylor and Francis Group, LLC i gure 3.1gure Alkaline electrolyte: Alkaline Theoretical voltage as Theoretical described of is electrolysis When reaction temperature (and pressure, to be accurate) are decided, heat and work and heat decided, are accurate) be to pressure, (and temperature reaction When Acid electrolyte: equa below.shown The as half-reactions two of combination a is water of Electrolysis

Principle Δ 2 H and O and , Δ Cathode: 2H Anode: 2OH Anode: H G 0 (Phase shiftisnotdescribedforsimplification) T Cathode: 2H 2 d of lower pressure are made by thermal equilibrium of equilibrium thermal by made are pressure lowerof . Note that the product gases of H of productgases the Notethat . Δ T Δ 2 Δ G H O Δ S (work) − 2

(heat)

O

G = → →

e Δ +

= 2H G H

+ 2e

nFE

T 2 + + O + −

2e T Δ + →

+ H Δ

− 0.5O

S

Nuclear Hydrogen Production Handbook Hydrogen Production Nuclear

0.5O H →

2

H + 2 T

2

+ Δ Δ 2

2OH d +

G H

2e

+ = 2e − T

− − T Δ

S 2 and O and 2 are the same same the are (3.5) (3.3) (3.6) (3.2) (3.4) (3.1) - Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Equation in Water Electrolysis Breakdown of cell voltage. of cell Breakdown F Equation components of 3.9. cell in as resistance ohmic and trodes Equation 3.10. lyte The and approximatearound electrodes. value of over by is described Tafelpotentials electro bulk between in compositiondifference the from made is rate.potential Over cal excess means voltage cell voltageto theoretical orderin to atcell reactions progress practi © 2011 byTaylor and Francis Group, LLC i gure 3.2 gure

Δ Actual cell voltage is greater than theoretical voltage because of over potential of elec of potential over of voltage because theoretical than greater voltage is cell Actual Breakdown of actual cell voltage cell Breakdown 3.2. ofFigure of actual Over in electrodes potential illustrated is G Equation 3.7. From Equations 3.6 and 3.7, theoretical voltage is described as in in as described is voltage theoretical 3.7, and 3.6 Equations From 3.7. Equation e depends on temperature, composition of electrolyte, and pressure of gas as as gas of pressure and electrolyte, of composition temperature, on depends

3.8.

E 0 Cell voltage, Ecell (V) ∆∆ EE GG Cu =+ E ee rre cell =+ nt 0

=

de

E    ns 0 E

+ RT ov.pot. ity nF

E , RT i ov.pot.A    (A

= ⋅ ⋅ /c ln

C ln m 1

       2

+        + )   

  

E C f p HO f ov.pot.C p 00 2 HO 22 ln ln 00 22 a    a    HO ⋅ HO 2 i ⋅    2

e Oh po An pote Ca    + f p

te th ode f p E mi oretical nt nt ode ov ohm c    ial, ial,    ov re 05 . 05

si er . E E        st        er ov ov vo

an .p .p

ltag ot ot ce, .C .A e, E

oh E m (3.10) (3.7) (3.8) (3.9) 85 - - - Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 This efficiency can be defined as ratio of thermoneutral voltage, thermoneutral of ratio as defined be can efficiency This no heat and heat as supply voltage. at requirement same the thermoneutral required is is loss Joule by 3.13.production Equationheat Theoretically, voltage in cell actual 3.12to OH should be supplied to operate the cell. This is the reason to use use to reason the is This cell. operatethe suppliedto be should ofwork only Not cell. the to supplied energy electric the to enthalpy for lower operation of required cell cost. are total optimization system and cell total the low. be can Designing cost cell and small made be However, can required. size is cell sity.power large, is density greater electric operation because higher costcurrent is When density.approximately toden current voltage cell total current large linear The in is high is resistance Ohmic electrodes. and circuit electric outer electrodes, between bubble gas 86 which are reduced more easily than H than easily more reduced are which cations contains electrolyte the When electricity. of agents transfer as worksolution lyte electro (AWE)the electrolysis in Ions alkaline-water cell. an of schematic a is 3.3 Figure 3.3.1 3.3 used. be to has methods those in definition same the methods, other with compared is electrolysis of waterefficiency When heat. thermochemical uses of splitting efficiency the work, electric uses 3.11 Equation in calculation ciency, water (see splitting Chapter, of that as such thermochemical 5.1). Section the While and direct contact of electrodes. Though asbestos was used first, alternative materials materials alternative first, used was asbestos Though electrodes. of contact direct and used together. times A porous diaphragm works for of preventing products mixture gases some are Pt as such easily more occurs reaction which on appliedcatalysts Electrode anode. for are metal series nickel or steel carbon low nickel-coated like materials resistant nickel or oxidation- mesh and Alkali- cells. Low-carbon-steel normal in cathode as electrodes. used is mesh for low-carbon-steel coated desired are bubbles product of ment detach good and electrolyte, with area contact large potential, over Low used. often is in chosen usually KOH order concentration is to High avoid solution of materials. of 25–30 corrosion cell electrolyte water.Alkaline only decompose to as so used is alkali © 2011 byTaylor and Francis Group, LLC Efficiency of a water electrolysis cell is defined in Equation 3.11 as the ratio of reaction reaction of ratio the Equation as 3.11 in defined is cell electrolysis water a of Efficiency components:of separator,electrolyte, resistance electric from made is resistance Ohmic It is noted that the efficiency of water electrolysis is a different concept from other effi other from concept different a is electrolysis water of efficiency the that noted is It

− , water decomposition reaction cannot progress. Therefore, a strong acid or strong strong or acid strong a Therefore, progress. cannot reaction decomposition water , Alkaline Water Electrolysis Alkaline

Outline η el . + E E == or anions which are oxidized more easily than than easily more oxidized are which anions or ce H ll ∆ W = H = ∆ nF nF W H E E

ce H Nuclear Hydrogen Production Handbook Hydrogen Production Nuclear ll

Δ H E H , not , defined by Equation by defined Δ G Δ but heat of heat but G as numerator. as

(3.12) (3.13) (3.11) wt% wt% T Δ S - - - - -

Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Water Electrolysis sis cells sis as mentionedcells chapter the ofintroduction in were this based on AWE. on Research Basic oftechnology conventional AWE cell is very old. The early waterindustrial electroly 3.3.2 repair. sible. However, a disadvantage has stack should that entire ofbe stopped case type in this floor the pos productioncomponents ofis cell mass and because type of unipolar that used than smaller is commonly area is type This current. electric small of instead large is Total cells. voltage many of connection serial a toequivalent is electrolyzer total tors.The flow separa work 3.33.5.or also reaction Electrodes as in used are and unit, neighboring reaction by generated Electrons cathode.Equation 3.2 or the 3.4 sideat cathode other in a cell unit compartment to are transferred the the anode of the and anode, the is electrode at top. the top. the drums from separatedside are One in electrolyte the and gas The of an The electrolysis. in made heat electrolyte is fed of from the bottom the the electrolyte and and mixture product gas flows release out to cell the through circulates Electrolyte cell. large plant and necessary.is area 3.5 of Figure a schematic illustrates a bipolar electrolysis cells among space requires type This cell. bipolar with compared smaller usually is sity However, low and current. leakage advantageousden simple is structure in current type large plants.in This is large. serial each with other in Severalcurrent connect cells electric Instead, parallel. are electrodes all because electrodes of pair a as same the is electrolyzer one in voltageTotal diaphragms. porous through transfer can Electrolyte electrolyte. of of a unipolar cell is shown Figure 3.4in . Several pairs of anode and cathode are in one tank low-temperatureand [7]. of asbestos resistance issues health-related considering tried composites fluoroethylene their were (PTFE),and such as potassium titanide, polyantimonic acid, oxide-coated metallic materials, polytetra cell. electrolysis alkaline-water of an Schematic F © 2011 byTaylor and Francis Group, LLC i gure 3.3 gure AWE are cells grouped into and unipolar bipolar electrolysis cells. A schematic diagram r esearch and Development and esearch

( on thesurface El ca El ect ect taly ro ro st de de ) El so ec (K lu tr H OH ti ol 2 on yt ) e Ca th – od Po eA ro us di a phr ag m nod + e El so ec (K O lu tr OH 2 ti ol on yt ) e 87 - - - - ­ Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 tion alkaline electrolyte. Low-carbon steel could be used for construction material with with confidence onlymaterial below 80°C. There construction were fewalternativesfor besides materials PTFE-based for used be could steel Low-carbon electrolyte. alkaline tion concentra high and temperature high resisted that materials the was issue important An reduced. be can resistance electric causes that gas product the of bubbles ofvolume that in advantageous also is pressure High liquid. as electrolyte the keeping for temperature the increase to necessary is pressure temperature.High at high small expected are trodes not so large (see 3.1 Figure of). overand electrolyte resistance ohmic And of potential elec 88 Schematic diagram of a bipolar AWE of abipolar cell. diagram Schematic F T supplyingby decreases cell the to ofenergy theoretical water electrolysis operation the temperature of the ing high, electrolysis pressure. is temperature and When of increas overhalf all the 1980s by first world.the performance high The aimed at study “advanced water electrolysis” out alkaline had carried been offrom the latter half 1970s to AWE cell. of aunipolar diagram Schematic F © 2011 byTaylor and Francis Group, LLC i i gure 3.5 gure 3.4 gure

El Ca me – so ect Po (K t lu mb hode r OH ro ti ous on rane ly te H ) + 2 O H A 2 2 node di Por ap H ous hr Δ 2 S as heat because temperature dependence of dependence temperature because heat as S ag Δ m O G decreases G considering Equationdecreases 3.1. Work input O An 2 2 Ca ode t hode H 2 Nuclear Hydrogen Production Handbook Hydrogen Production Nuclear H Ca 2 t O hode 2 A node + El El solu (K El O ec ec ect 2 OH tr tr ti rolyte ol ol on) yt yt e, e,

– H O 2 2 Δ H is is H - - - Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 though coal gasification was most economic in the case of ca. 100,000 ca. of case the in economic most was gasification coal though production capacity was operated under 120°C and 20 test cell (20–30 cell test 1975. since electrocatalysts and materials, bench-scaled A diaphragm,electrode structure, of small-scale commercial AWE systems as of August, 2009. It is noted that data is not is data that noted is It 2009. August, of as systems AWE commercial small-scale of were available. water pure of amounts large and generation hydroelectric low-cost where selected were Sites plants. hydrogen-production mass industrial of examples chapter.this shows3.1 Tableof introduction the in explained as old very is AWE large-scale of Industrialization 3.3.3 [5].at period the below in 100°C targets by improvementmain the became of electrodes ing of hydrocarbon was available. Reduction of cell voltage and of increase density current on advancedresearch AWE reduced the mid-1980sin since low price hydrogen by reform at operating cell test long-term a 150°C [14]. of construction for researched and materials catalyst electro and separator promising on studied laboratory 1979. The from worked Canada, [11]. the electrolyzer under 120°C and 20 and 120°C under electrolyzer the tories. Their theme was improvement of operating current density and energy efficiency of and Technology)Science Industrial of and severala consortium public and private labora Advanced of Institute NationalCenter, Kansai (now(ONRI) Institute Research National developmentthe of alternative studysources. The energy was atconducted Osaka mainly advanced AWE [8]. National Brookhaven objective. the for universities some with electrodes screening, foron (BNL),Laboratory mainly USA, conducted investigatedtrials Material were upon. evaluation focused cost were and separator design, electrode life long a and materials electrode alternative including catalyst/electrodestructure of improvement125°C, over since 1976 supported by U.S. of Department (DOE).Energy Operation at temperature high was adiaphragm investigated. and electrode an between distance small of designs cell and studied were materials New research. the of target a was diaphragm substituting materials diaphragm asbestos [2]. novel And reduction as ofby resistance electric improvement of proposed and electrodes porous were acid polyantimonic and ate use as gasket materials atand insulating temperatures higher 100°C.than Potassium titan Water Electrolysis density. Operating temperature was set mainly on 120–200°C though some researches researches some though were 120–200°Con around 90°C. Target on of density current was 1 mainly current set increase was to temperature and voltage Operating cell density. total lower to order in concept cell total and tions, condi operating electrolytes,of nature R&D components,materials, on the constituent in participated contractors Many Programmes. Framework 2nd 1stResearch and the within hydrogension oxygen into by operation mixing was aproblem [3]. high-pressure in among gas reforming and coal gasification in small plant of 15 of plant small in gasification coal and reforming gas among conducted based on the data from these cells. Electrolysis was estimated as most economic 3–10of (120°C) cells pilot © 2011 byTaylor and Francis Group, LLC Smaller size AWE systems were commercialized afterwards. Tableafterwards. examplesshows3.2 commercialized wereAWE systems size Smaller of Activity cost. productionhydrogen increased materials resistant alkali of cost High In In Japan, study on AWE began 1975in as a plan Project, ofwhich had atSunshine aimed AWEadvanced developmentof in involved been had USA,Systems, TeledyneEnergy European Community (EC)European Community had also R&D 1975–1979in programs [10] and 1979–1984 [11]

lcrct d Fac ad a d Fac as hd en netgtn mtras for materials investigating been had also France de Gaz and France de Electricité

Industrialization

kW) design was also carried out from 1978 outfrom [13]. carried Center,also was kW) Research design Noranda

kW scale were developed(e.g.,were was scale kW [12])analysis economic and

kg/cm 2 [9]. A pilot plant of 20 of plant pilot [9].A

A/cm

kg/cm 2 . Three . moderateThree temperature 2 by mid-1980s. Risk of explo

Nm 3

/h hydrogen at 1984at hydrogen /h Nm

Nm 3 /h of hydrogen of /h 3 /h hydrogen /h 89 ------Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Lurgi GmbH De Nora Demag Norsk Hydro Norsk Hydro Cominco Brown Boveri Norsk Hydro Lurgi GmbH De Nora Demag Cominco These plantsare notalwaysat workasof August 2009. Norsk Hydro Norsk Hydro Norsk Hydro Norsk Hydro Norsk Hydro Norsk Hydro Norsk Hydro d c b a Establishment ofthePlant) Manufacturer (Atthe Brown Boveri of thePlant) Establishment (At the Manufacturer Plants Hydrogen Production Electrolysis ofExample Large-Scale Table 3.1 © 2011 byTaylor and Francis Group, LLC

Began in 1927.Upgraded through 1965. Statoil andoil& gas divisionofNorskHydro merged intoStatoilHydro. At present, marketingandrealization ofnew installationandthemaintenance ofexistingsiteswastransferred from Lurgi. Brown Boveriand Asea AB merged into ASEA Brown Boveri. b b c c c c c c c c c c a a Italy Germany Canada Norway Norway Norway Norway Norway Germany Switzerland Manufacturer Nation of Reference Nangal Aswan Trail Rjukan Glomfjord Fredrikstad Reykjavik Kristiansand Cuzco Aswan [16] [15] [15] [15] [15] [15] [15] [16] [16] [16] Site India Egypt Canada Norway Norway Norway Iceland Norway Peru Egypt Nation of Site Operation athighpressure (30(kg/cm Type: Ref.[17],Objective: [1] Type: Ref.[17],Objective: [16] Type: Ref.[17],Objective: [18] Replacement oftheDemagplant Type: Ref.[17], Hydrogen production: Ref. [5],Objective:[1] Establishment year (timeofstartoperation):Ref.[1] Filter press Filter press Tank Filter press Filter press Type Establishment Note 1958 1960 1939 1927 1950 1958 1977 Year 2 )) d Production Hydrogen (Nm 26000 41000 17000 21600 27900 6800 5000 1800 2600 1050 3 /h) Ammonia synthesis Ammonia synthesis Manufacture offertilizer Ammonia synthesis Ammonia synthesis Ammonia synthesis Ammonia synthesis Nickel refining Ammonia synthesis

Objective

Nuclear Hydrogen Production Handbook Production Hydrogen Nuclear 90 Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Water Electrolysis Industrie Haute Company Teledyne Energy Industrie Haute Hydrogenics Hydrogenics Avalence r q p o n m l k j i h g f e d c b a StatoilHydro Industrie Haute Company Water(AWE)Electrolysis Alkaline Cells Commercial Scale of Small ofExample Specification Table 3.2 Teledyne Energy Teledyne Energy Teledyne Energy StatoilHydro Industrie Haute Hydrogenics Hydrogenics Avalence © 2011 byTaylor and Francis Group, LLC

Technologie Systems Technologie Technologie Systems Systems Systems Technologie

Estimation bythe descriptionofRef.[16]. At 0°C,1013 At 20°C,1013 Electrolysis only. Of Hydrofiller 175. Of Hydrofiller 50. Of Hydrofiller 15. Including rectifier andauxiliaries. 25 Cell isatatmosphericpressure andproduct gasispressurized atdelivery. At 5150 At 4000 Estimation bythedescriptionofRef.[3]. Ref. [24]. Statoil andoil&gasdivisionofNorskHydro merged intoStatoilHydro. from Lurgi, whichhadsoldBamagcell. transferred was sites existing of maintenance the and istallation new of realization and marketing present, At from Lurgi. transferred was sites existing of maintenance the and istallation new of realization and marketing present, At Though IMETwasdealtbyStuartEnergy, Hydrogenics hasacquired StuartEnergy.

atm isavailableonlyupto30

Amp DC. Amp DC. a a a a d d c b c b

mbar, day.

mbar, wet.

Pressure (atm) 650 Atmospheric Atmospheric 32 10 25 4.2–8.1 10 USA Norway Switzerland USA Switzerland Canada Canada Maximum i i, j i Nation

psi i i

Nm 3 /h andpowerconsumptionof4.9 TITAN EC TITAN HM IMET 1000 IMET 300 Hydrofiller Purity (%) Hydrogen 99.9 99.8–99.9 99.8–99.9 99.9998 99.9998 99.9 99.9 99.7 Model

e ±

0.1 Bipolar Bipolar Bipolar Bipolar Bipolar Bipolar Bipolar Unipolar Type Electricity Consumption 4.1 3.90–4.22 4.3–4.6 5.6 5.6–6.4 4.2 4.2 5.1

r o o e, k,l ± , 4.8 , 4.9 e e e e f f

(kWh/ 0.1 e , 5.3 r k k g

kWh/Nm , 4.3 p , 4.20–4.54 e, k,m ­Nm

± , 5.4

3 0.1 ) Production Hydrogen 110–760 (Nm h 2.8–11.2 0.4–4.6 e, k,n 10–485 10–377 28–56 3 h. 3–330 4–60 1–3 q 3 /h) h g , Temperature Maximum Reference (°C) [21] [23] [23] [22] [21] [20] [20] [19] 90 80 80 f f 91 Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 used because of its excellent thermal resistance and oxidation and 3.7 Figure of because resistance itsresistance. used excellentshows thermal has already reached the limit. For example, the efficiency of the cell alone defined in defined alone cell the of efficiency the example, For limit. the reached already has are commonly used now [25]. Technology of conventional AWE has and matured property and bipolar werecells 1970s,in used unipolar the latter both operating at temperatures lower Though 100°C than cell. pressurized large-scale commercial only the is system Lurgi for storage of hydrogen is preferable to electrolyzer pressurized for and safety economycompressor a [3]. and cell electrolysis pressure atmospheric an of However, combination the at overoperating 3.0 in shown Section 3.3.2 as . Lurgi advantageousUmwelt is GmbH, und Chemotechnik Germany,electrolysis a manufactured module Pressurized standard. uniform on ­necessarily 92 Schematic diagram of a PEWE cell. of aPEWE diagram Schematic F Perfluorosulfonic acid polymer membranes, suchas Nafion hydrogen is generated at the cathode. The PEM worksalso as a separator of product gases. side, and cathode to PEM the through transported are protons The electrode. plateto lar allow toelectrons transfer from electrode to outer circuit and allow reactant that gas conductors from bipoporous are collectors Current protons. make to reacts and collector, rent side only of the bipolar plate. The water flowsfromthe plate thetheanodetocur through brane shownEquations are 3.2in and 3.3.mem Reactant ofwater anode the cation-exchange fed is into channels a using reactions The cell. a of schematic a shows 3.6 Figure too. electrolysis, water (PEM) membrane exchange proton or membrane electrolyte polymer medium of ofioninstead solutiontransfer AWE.electrolyte in is method often called This a as membrane electrolyte polymer a uses (PEWE) electrolysis water Polymerelectrolyte 3.4.1 3.4 Hydrogenics IMET in 73% is auxiliaries and rectifier including system total of that 3.11and 83%Equation is © 2011 byTaylor and Francis Group, LLC i gure 3.6 gure

Polymer Water Electrolyte Electrolysis

Outline ® 1000 [24].

MPa(now Haute available Industrie Technologie, from Switzerland). co Cu pl Bi ll rr ec at pol H en e to 2 ar t

r (H 2 O) Ca (H – H th 2 O) 2 od me Po e ly mb me (H ra r H ne 2 el + O) ect (P EM rolyte An Nuclear Hydrogen Production Handbook Hydrogen Production Nuclear ) ode O H + 2 2 O H 2 O O ® 2 , of DuPont, USA, are typically H 2 pl Bi O at po e la r - - - Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Chemical structure of Nafion. structure Chemical F Water Electrolysis groups ( of Nafion. Thestructure the chemical membrane worksas strong acid due theto sulfonate with GE began in 1975 and resulted in the operation of a 200 a of operation the in resulted 1975 and in began GE with effort DOE The program. space Gemini the in cell fuel electrolyte polymer of technology the using 1966 in (GE), USA, Electric General by out carried was PEWE of trial first The 3.4.2 cathode as [26]. stability. used commonly Pt is Metallic structural componentsfor inert with mixed often material. are materials of These used. selection are Ru and Ir ofby Oxides influenced is it and potential over cell total the of source main the is potential Platinum over Cathode electrodes. electrodes. for used AWE are Pt for of oxide and alloy requirements metal, group the to addition in electrodes for required is PEM the of acidity strong to resistance Corrosion resistance. electric avoidinterface to cell sealing, water purity, and cell impedance. The costly PEM, electrodes and current current and electrodes PEM, costly The impedance. cell and purity, water sealing, cell were problems technological major The developed.were resistance collector current the lowering technology manufacturing and PEMs thinner of Application cells. electrolysis © 2011 byTaylor and Francis Group, LLC i gure 3.7 gure Disadvantages: Advantages: AWEAdvantages compared with method follows disadvantages as and of are this [3]. 2. 2. 4. 4. 3. 3. 1. 1.

r Cost of the PEM, electrodes and current collectors is high. is collectors Cost current PEM, of and the electrodes (around 0–5%). PEM the within gas of permeation backward from resulting loss current Electric resistance. electric Uniform contact between the PEM and the electrodes should be achieved to reduce dueshould corrosion be PEM. resistant of acidity to strong the collectors) (electrodes,current PEM the with contact in come which Components good and electrolyte product separation PEM. gas by the solution of droplets no with high is gas product of Purity made. be can by bubbles electrodes gas resistance between No electric side cathodeand side allowed. is anode between difference pressure because easy is facility of Construction to maintain. wide easy is and selection Corrosive liquid electrolyte is not Therefore,required. range material of structural esearch and Development and esearch − SO 3 H) at the end of side Electrodes come chains. in contact with directly the PEM

CF 2 –CF 2 n O CF – CF –CF 2 –CF 2

CF x 3

m O – CF 2 –CF 2 –SO

kW system consisting of 60 of consisting kWsystem 3 H 93 Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Proton Energy energy conversion efficiency was attained at 120°C,at 0.5 attained conversionwas efficiency energy 0.5 25,000 for performed was test electrolysis scale laboratory- A developed. was composite (EME) electrode–membrane–electrode efficient were cell operated 1990s in [29]. type this demonstration plants using hydrogen-production capacity operated for more than 6000 trode trode area of 50 elec of cell a of schedule).Operation original the in 2003 from up moved was year (end 2002 1993to(NEDO), Japan,from Development TechnologyOrganization Industrial and project Sunshine of successor (1973–1991) a was and New project which Sunshine (1992–2000), project, (WE-NET) had been Networkbyadministrated New Energy Energy World Kobelco Proton Energy civd y pca paig ehd [] Fo 17 t 18 Bon oei Switzerland Boveri,3 pilot A plant with cell. commercial a on (now BrownBrownBoveri) researched Asea also 1989 to 1976 From [9]. methods plating special by achieved was catalysts electrode Sunshine for loading in metal noble ONRI of 3.3.2).Reduction by Chapter (see conducted Project was research a Japan, In [8]. interface electrocatalyst PEM/ on works conducted1981. BNL in stopped DOE the from GE to support funding prevented­collectors cost goal to achievedbe the for hydrogen production The at time. the 94 A cell stack test equipment with electrode area of 2500 of area electrode with equipment test stack cell A f e d c b a Company (PEWE) Cells Electrolyte WaterPolymer Electrolytes of Commercial ofExample Specification Table 3.3 cient PEWE in the scale of severalm of scale European the in PEWEcient of develop effi to Programme was program the of Research objective main Framework The 2008. to 6th 2005 from Commission the of project a as conducted was program (GenHyPEM) l’eauPEM de électrolyse par d’Hydrogène Générateur Recently, at and improvementPt electrode [33]. of durability [31,32]. at reduction WE-NET of project,of After aiming mass NEDO continued a research sity and 50 and sity catalysts [34]. Russian Research Center Kurchatov Institute has studied PEWE for PEWE over 20studied has Institute Center Kurchatov [34].catalysts Research Russian the PEM and non-noble weremetal electrocatalysts investigated in order to reduce cost of h-tec © 2011 byTaylor and Francis Group, LLC

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Reaction Gibbs energy ( Reaction Gibbs energy Reaction entropy (kJ/K) Reaction enthalpy (kJ) ofGibbs (kJ/mol) electrolysis energy Standard pressure ( pressure Standard Standard state (298Standard 10 Kand Cathode Anode Efficiency of water electrolysis (dimensionless) Over potential resistance Ohmic Electric energy consumption (kJ) consumption energy Electric of temperature Δ The Reaction temperature (K)Reaction temperature Activity of component liquid Activity (dimensionless) Thermoneutral voltageThermoneutral (V) voltageTheoretical (V) on temperature, state, surface depending material Constants electrode and Molar ratio of transferred electron to decomposed water electron ( Molar ratio of transferred Standard theoretical voltage theoretical Standard ( Cell voltageCell (V) Current density (A/cmCurrent density Faraday ( constant ronment) (Pa) Fugacity of gas component (canatpressure as be lowpartial taken envi pressure

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© 2011 byTaylor and Francis Group, LLC 10. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 11.

1. 2. 3. 4. 5. 6. 7. 8. 9.

21–43, Toronto, Canada,July15–20,1984. d’hydrogene. production de siecles Deux R., Aureille, 1983. LeRoy, R. L., Industrial water electrolysis: Present and future. Tokyo, NTS. Abe, I., Arukari mizu denkaihou. In denkaihou. mizu Arukari I., Abe, T. In denkaihou. mizu koubunsigata Kotai K., Takenaka, Japan, 371–380,2000,Tokyo, Maruzen. In denkai. Mizu K., Takenaka, 344–355, 2007,Tokyo, NTS. In gijyutu. seizou suiso yoru ni denkai Takenaka,Mizu K., Hydrogen Energy , 7,155–166,1982. electrolysers. water alkaline in use for materials LeRoy,Separator L. R. and R. Renaud, 275, 1984. abroad. and States United the in production hydrogen trolytic Bonner,T.M., McBreen,F. J. Mezzina, Botts, A. C. Yang, and elec- Salzano, advanced of Status Ohta, T. and M. V. C. Sastri, Hydrogen energy research programs in Japan. Energy, 4,489–498,1979. in programs research energy Hydrogen Sastri, V.C. M. and T. Ohta, of theEuropean Communities. Int.J.Hydrogen Energy, 6,153–158,1981. programme hydrogen first the of conclusion the at electrolysis water in Progress G., Imarisio, J. Appl.Electrochem., 18,1–14,1988. trolysis. A review of the research programme of the Commission of elec- the water Europeanadvanced on Communities. development and research of years Nine Imarisio, G. Wendt,and H. 277–284, 1984. electrolysis. water alkaline advanced on Belgium in work R&D sive inten- year five van Asbroeck,of APh. survey and Nackaerts, H. Vandenborre,Leysen, R. H., chemical engineeringfrom 1975to1982.Int.J.Hydrogen Energy, 8,529–538,1983. electro- in activity water-EGF of electrolysis Alkaline Montet, A. and Damien, A. C., Bailleux, in advancedalkalinewaterelectrolysis. Int.J.Hydrogen Energy, 9,59–66,1984. Bowen, C. T., H. J. Davis, B. F. Henshaw, R. Lachance, R. L. LeRoy, and R. Renaud, Developments Vol. 1,eds.Cox,K.E.,andD.Williamson, 3–41,1977,Cleveland, CRCPress. Fickett, A. P. and F. R. Kalhammer, Water electrolysis. In Lyon, France,June13–16,2006. Bello, B. and M. Junker., Large scale electrolysers. Hydrogen Energy. to Hydrogen Energy, ed., T. N. Veziroglu, 19–49, 1975, Coral Gables, International Association for Funk, J. E., Thermochemical and electrolytic production of hydrogen from water. In Proc. 1stWorld Hydrogen Energy Conf.6B-3–6B19,MiamiBeach,U.S.,March 1–3,1976. Laskin, J. B. and R. D. Feldwick, Recent development of large electrolytic hydrogen generators. Avalence. http://www.avalence.com/ (accessed August 20,2009). Hydrogenics. http://www.hydrogenics.com/default.asp (accessed August 20,2009). http://www.iht.ch/technologie/electrolysis/industry/ Technologie. Haute tailormade-installations.html (accessed August 20,2009). Industrie StatoilHydro. http://www.electrolysers.com/ (accessed August 20,2009). (cesd uut 20, August (accessed http://www.teledynees.com/index.asp2009). Systems. Energy Teledyne v, . Smay f lcrltc yrgn rdcin ietn cmlto report. completion milestone MP-560-36734, 2004. production hydrogen electrolytic of Summary J., Ivy,

Ohta, 74–84,1995,Tokyo, NTS. 5h dto, lcrceia Scey of Society Electrochemical edition, 5th Binran, Kagaku Denki , ed. T. Ohta, 37–58, 1995, 37–58, T.Ohta, ed. Gijyutu, Saisentan Enerugi Suiso Proc. 16th World Hydrogen Energy Conf. II-215, Nuclear Hydrogen Production Handbook Hydrogen Production Nuclear Hydrogen: Its Technology and Implications, Proc. 5th World Hydrogen Energy Conf., Energy Hydrogen World 5th Proc. ed. Gijyutu, Saisentan Enerugi Suiso , Vol.Syuusei, Gijyutu 3, Riyou Suiso Int. J. Hydrogen Energy, 8, 401–417, , 9, 269– 9, Energy , Hydrogen J. Int. , 9, Energy, Hydrogen J. Int. Int. J. Hydrogen J. Int. Introduction NREL/ Int. J. Int. ­ Downloaded By: 10.3.98.104 At: 11:18 28 Sep 2021; For: 9781439810842, chapter3, 10.1201/b10789-6 Water Electrolysis

© 2011 byTaylor and Francis Group, LLC 25. 29. 26. 30. 27. 31. 28. 32. 33. 34. 35. 36. 37. 38. 39.

World Hydrogen Energy Conf.333–340,Vienna, Austria, July20–24,1986. Thesis, Technical Univ. Eindhoven,2006. Master 1970s, the since technologies production hydrogen of Expectations S., J. Welboren,D. membrane failure in100 for Fischer,Scherer,Evidence electrolysers:E. G. water and G. PEM Schlagowski, S., S. Stucki, electrolyte. Electrochim., 48,3945–3952,2003. Acta polymer solid with electrolysis water Tunold,in ElectrocatalysisR. and Hagen, G. E., Rasten, water electrolyzer. Int.J.Hydrogen Energy, 21,87–93,1996. Millet, P., F. Andolfatto, and R. Durand, Design and performance of a solid polymer electrolyte Proc. 3rdWorld Hydrogen Energy Conf.1799–1808,Tokyo, Japan,June23–26,1980. Stucki, S. and R. Müller, Evaluation of materials for a water electrolyzer of the membrane type. energy (WE-NET).Int.J.Hydrogen Energy , 27,115–129, 2002. hydrogenusing T.,energynetwork Hijikata, clean international of development Researchand Oberlin, R. and M. Fischer, Status of the MEMBREL the of Status Fischer, M. and R. Oberlin, 2003. Organization, Development Technology Industrial and Energy New e Eeg ad nutil ehooy eeomn Organization, 2008. Development Technology Industrial and Energy New 34, Commission. European the by supported electrolysis water PEM on P.,Millet, Grigoriev,S. Dragoe, D. V. Fateev, GenHyPEM: Etievant, AC. and research program sis forhydrogen energy. Int.J.Hydrogen Energy , 31,171–175,2006. Grigoriev. S. A., V. I. Porembsky, and V. N. Fateev, Pure hydrogen production by PEM electroly- 2009). 20, August (accessed h-tec. http://www.h-tec.com/html/web/industrial/english/index.asp http://www.kobelco-eco.co.jp/product/suisohassei/hhog_seihin. html (accessed August 20,2009). Eco-Solutions. Kobelco Proton Energy Systems.http://www.protonenergy.com/ (accessed August 20,2009). 2003. Organization, Development Technology Industrial and Energy New

4974–4982, 2009.

kW demonstrationplants.J.Appl.Electrochem., 28,1041–1049,1998. ® process for water electrolysis. water for process Int. J. Hydrogen Energy, Hydrogen J. Int. EO WE-NET-0208, NEDO EO WE-NET-0201, NEDO EO 06990091-0-1, NEDO Proc. 6th Proc. 97