Reaction of Cerium Dioxide with Alkali Metal Alkoxides
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REACTIOREACTION N OOF F CERIUCERIUM M DIOXIDDIOXIDE E WITWITH H ALKALALKALI I METAMETAL L ALKOXIDESALKOXIDES. .
NOBUAKNOBU AKl I SATSATO O ANAND D TAKEOTAKEOFUJIN FUJ 刷 O Rcscarch ResearcRcscarch h InstitutIn stitutc e oof f MineraMinetal l DressinDrcssing g anand d Metallurgy,， ToftokTohoku u UniversityUniversily ,， KatahiraKa凶 nra ,， SendaScndai i 9809剖 ,'， JAPAJAPAN N Phone PhonPhone e 022-227-6200,， FAFAX X 022-261-0938022-261-093 8
ABSTRACAHSTRACT T tiotion n oof f Ce0Ce02 2 anand d metarnetal l calciucalcium m formforms s CaoO anand d CeCeO O at at 1273 1271273 3 Kll). K").
ThThc e gas-soligas-solid d reactiorcaction n procespmccss s usinusing g volatilvolatik e alkali alkali hIn 也thiis s paper,， wwe e studstudy y 也巴the reactioreaction n betweebetween n Ce0Ce o22 Jud md rnctal metarnctal l alkoxidealkoxidcs s hahas s manrnany y advantageadvantagcs s iin n producinprodu c.i ng g ththc e MOBuMOBu' 1 (M=Li(M= Li， , KK) ) fofor r ththe e formatioformation n oof f ，comple 'umplex x oxide oxide uranatcs(plutonatcs) uranatcs(plutonatcsuranatcs(plutonatcs) ) whicwhich h ararc e expectecxpectcd d tto o improvirnprovc e thc the undeunder r severasever 司l ∞conditionsnditions ,，∞ comparinmp 宿泊g witwith h 白thosose e obobtaine凶 ned d dissolution dissolutiodissolution n behaviobehavior r oof f ththc e fuefucl into l into nitrinitric c acidacid. . IIn n this this bby y aan n aqueouaqueous s memethod出od. .
work. workwork. , ththc e reactionrcactioss s oof f Ce0CcO? 2, whicwhich h wawas s useused d aas s a non-non radioactivc radioactivc stand-in of puO with MOBu' 1 (M= K) radioactive stand-in of Pubz2,， wit h MOBu (M=Li Li， , K) undcr undcr unde r scveral severa l conditions conditions wcrewere examined. examined. In In the the case case ofof 白thCe 2.EXPERI2.EXPERIMENTAL品位NTALS S
M!"I >~cvCeトデ1.>.0O 22_.，x synthc~~z~~synthesized byb y anan aqaqueoul! eo .u .s s .metho~method,， t~~the latiicc latiicc lattic e pararnctcr parameter waswa s slightly slightly increased increased with wit h increasing increasing M 2.1 2.1 SampleSampl e preparation preparation conccntration concentration,， y ，, upu p to to 0.20. 0.20. WhenWhe n the the Li LiOBuOBu' ' vaporvapor Li Lithiu thium m andand pot potassiu蹴 ium m t-butoxide t-butoxide werewer e synthesized synthesized byb y rcactcd rcactcd reacted with with CcOηaCcO „ a newne w fluoritc fluoritc phase phase having having a=5a=5.493.4 935 5 the the reaction reaction ofof each each metal metal withwith t-BuOH.t-BuOH. 百Thle e t-BuOHt-BuO H えX. γ=0.044.v=0.044. x=O.30x=0.30 waswa s forrncd formed over over 97397 3 K.K. A similar similar waswa s dehydrated dehydrated using using dried dried molecular molecular sieves sieves before before use use cocompounIn pound d (a=5 (a=5.479.4- 797 7 A， %,y=0.035 y=0.035， x=0.22) , x=0.22 )was wa sobscrved observedby by because because of of the the hygros hygroscopi∞picpropc c propertie凶 cs s ofof 也the metmeta aI l alkox- alkox thc thc th e rcaction reaction of of CeO ヲ, with with KOBu'.KOBu'. ides. ides. Special Special commercialcommercial grade grade ofof Ce02Ce0 2 and and t-BuOHt-BuO H KcywordsKeyword s : solid solid solution,， alkoxide ，, ccriurn ceriu m oxide ，, from from WakoWak o PuPur re e Chemicals Chemicals Co. Co. Lt Ltd d. . werewere used. used. 醐 gas-solid gas-solid gas-solid rcaction reaction,， MOXMO X fu fuel e/， , volat volatili! e process. process. 百Thle e CeCe0o22 solid soli d solution solution ωcontaininining g the the knownknow n amounl amount of of o f lithium lithium or or popotassiu泊ssium m waswa s obtained obtained byb y drying drying homoge-homoge
1. 1. 1. lNTRODUCTlONINTRODUCTIO N nized nized solution solution ofof Ce(NH4h(4)2(N0N0 33)6 )6 andan d 'Li LiOHHOH'H 220- 0 or or K 22Cz C2004 4 合'Ofromm WakoWak o Pure Chemicals Chemicals Co. Co. Lt Ltd.d. ，, followed followe d by by MixcdMixe d oxide oxid e forrnation formation with wit h rnetal alkali alkali metal 加from pluto- pluto- calcination calcination in in air air at at 11731173 K for for 10 10 hours. hours. niurn-uraniurn niurn-uraniurn nium-uranium dioxide dioxide fuel fuel is is expect expecter. d to t o result result in in great great cnhanccrncnt cnhanccrncnt enhancement of of thc th e dissolution dissolutio n rau:: rate of of spent spent into fuel fuel into 2.2 2.2 Reaction Reaction prωedureprocedur e v nitr;~nitr "~id."dd. For For producing producing such such uranatcs(plutonates) uranates(plutonates)，, the th e Ce02Ce0 2 and and MOBu'MOBu ' werewere placed placed 恒in a quartz quartz double doubl e cell cell ga ga ga I' rcactlon reaction proccss process using usin g volatile volatile compoundscompound s of of separately separately after after weighing weighing in in 相an argon argon utmospheric atmospheric glove glove I. aLI. Ictals ictals ，, is is advantageous advantageous comparing comparing with with 出the solid- solid- box. box. TheTh e doubledouble celi cell waswa s set set in in a twotw o stage stage heater heater as as solid solid soli d rcaction reaction in i n reaction reactio n efficiency efficiency andan d hornogencity homogeneity of of shownshow n in in FigureFigure 1 after after ssealin巴aling g underunde r vacuum.vacuum . TheTh e t thc thc the formcd formed mixcdmixe d uranium uranium oxides. oxides. OneOn e of of such suc h volatile volatile MOBu ' Wwa錨s heated heated for fo r vaporizing to to react react with with CeCe0oz2 ぽat
compoundscompound s is is metal metal alkoxides(M(OR) alkoxides(M(OR) ，). x). Mhig俳句h temperaturmp ぽ aωre e part. part. AAfte批 r 血there reaction，伺 ction. , 出直the identification identification Gcnerally Gcnerally Generally spcaking speaking ，, alkoxides alkoxide s have hav e increasing increasing volatili- volatili o.f f the the product product by by X-rayX-ra y djffracti diffractio∞n andand chemical chemica l analysis analysis ty ty ty with with incrcasing increasing side side chain chain of of alcohol alcohol，, while whil e they they are are wereconducted. were conducted. increasingly increasingly increasingly hygroscopic hygroscopic andan d thermally thermally unstable1l. unstable'). Buthoxides(MOBuButhoxides(MOBu') arc are knownknow n to to have have the th e highest highest vola- vola ' 2 tility tility tility amongamon g alkali alkali metal metal alkoxides(MOR alkoxides(MOR) )2 l. ). TtT.C. 監2記長。切断 ate 封切や ヲ CcOCe02 is is uscd used as as a a non-radioactive non-radioactive stand-in stand-in of of PuO?Pu0 2. Sincc Sincc U0 and alkali metals forrn many types of Since U022 and alkali metals form many types of com~com 33 3 pounds such as Li U0 >, M U,_ 0+x 3l ', similar reaction pou~ds such as ，u Z2U
OnO n thc the othcr other hand hand， , the th e nonstoichiornetry nonstoichiometry of of Ce02Ce0 2 has has long long bccn bccn been studied studied in in connection connection with with thermodynamksthermodynamirs44--66)，, Quartz tube 7 8 9 mW$ß.] ~mω臨凶@ structurcstructure7•S' )' and an d elcctrical electrical cconduction唖nduction 9). ). TheTh e subphase subphase 10 digaram digaram waswa s gh'cn given by by BevanB e van et e al t allO )). . showing showing manyman y Fi Figur伊 re e 1 1 Experimental Experimental app apparatus祖国.. ox oxyge'y gcn n difficient diffident oxides oxides，, CeOz_ Ce0 2.x5 (O.Ol 163-163 In In thc casc of Li .Cc O _. ， thc !atticc paramcter was 2.3 2.2.3 3 X-raX-ra¥' y MeasuremenMcasurcmcnt t In the case of LiyCe^.O,-,1 市 2 , the lattice parameter was X-raX -ray y diffractiodiffr3ction n experimentcxpcrirncn~s、 werwcrce carriecarricd d ouout t witwith h a slightlsli giJ tly y increaseincre ぉcd d witwitli h increasinincreasing g lithiulithium m concentration∞nc 四国tion ,， yy Rigak Rigaku u RAD-1RAD-I BB diffractomclediffractornctcr r syste system m usinusing g CuKαCuK a uuω0.19p to 0.19 a凶s showshown n iin n FigurFigu 問e 22. . Th ec relatiorclation n betweebetwccn n ththe e radiation. radiationradiation. . Th ec slislit t systesystcm m useuscd d wawas s 1.0-0.3mm-1.0l. O-O .3 mm- l. O. . Thec valuev1ilues s oofx f x an組 ddy y alsalso o iis s showshown n aas s a straighstraight t linlinc e acrossinaα -o ss 泊g diffraction diffractiodiffraction n anglanglc e wawas s correctecorrccted d usinusing g a silicosilicon n standarstandard d zerzero o poinpO int t aas s seesccn n iin n FigurFi l?ll rc e 22. . samplc. samplesamplc. . ThThc e latticlatticc e parameterparamctcr ,、 a,， wawas s determinedctcrmined d bby y ththc e ThTIi ec latticlatticc e parametepru 百metcr r anand d x-valuX-¥' ・alue e o of f KyCe^O^K."Ce I_.0 2_,克明町 were NcJson-Rile Nclson-Rilcy v extrapolatiocxtrapohition n methorncthod d fofor r ththc e highigh h anglanglc e increaseincrcased d linearl:lim1r ly y witwith h increasinincreasing g potassiupotassium m 凶concentranccn 回目 0 0 pcaks peakpcaks s (60 (60°<28<135°)<26 <135 ). . tiotion n uup p to10 0.20.20 0 aas s showshown n iin n FigurFigure e 33. . 5 14 ，0 .5 .4 2.2.4 4 ChemicaChcmical l analysianalysis s oof f oxygeoxygcn n anand d alkalalkali i metamctal l ‘ ThηJC e oxygeoxygcn n contenconlcnt t iin n ththe e productproducts s wawas s determinedetermined d bby y inerinc Tl t gagas s fusiofusion n analysisanalysis.ηJC . Th e alkalalkali i metamctal l conccntration concentration 5.' ・13 1M in iin n ththc e producproduct t wawas s determinedctcrmincd d bby y atomiatomic c absorption absorption << analysis analysis aftcr 山 solving the product in H S0 -HF( 1O :1) 5.412 。" analysis after dissolving the product in H22SO44-HF(10:l) 《 0.3 ~ solution叩 lution. . ・4 " ~5 u -h 圃 3. 33. . RESULTRESULTS S ANDANO D1DISCUSSIONSCUSSIONS S 0.2 凶 5.4 日1 .e .1 3.3.1 1 RelatioRclation n oof f latticlatticc e parameteoardmctcr r witwith h x anand d yv oof f 0.1 0.1 H MyCCj.-.O,.,M ，CC H 0 2_x, (M=Li,K(M= Li， K) ) obtaine01 ヲtaincd d b by y aqueouaquco 凶s methorncthod d Fluorite FliioritFluorite c typtypc e solisolid d solutionsolutions s o of f M，y.Cc1_y02 Ce,./)2_寸x wcrcwere formcd formeformcd d from from ththc e aqueouaQUCOUs s solutiosoIution n oof f LiLF* an and d fceC c4+ 4* aas s welwe l1 l as aas s thathat t oof f KK+ * anand d Ce^Ce 4+. . ResultR 回 ults s o of f latticIattice e parameterspa IaIs etcrs ,， x-x - 0.00.05 5 0.0.1 1 0.10.15 S 。0..2 2 and anand d y-valucy-¥'a1:.:ω(}f s of Mj.Cc,_M.CC _ 0v0 2__. , arare e givegivcn n iin n TableTablcs s 1 anand d 2. 2. 1 v 2 y iID n K)'Cel_ K,Ce,.，. yOj.OZ_. » Tablc TablTablc e 1 y-,， x-valuex-valucs s anand d latticlattice e parameteparamcter r oof f FigurFigure e 3 RelatioRelation n betweebetween n latticlatticc e parameterpru 迦 netcr ,， x anand d y-y- Li CC _ 02 寸 prcpared by aqucous method. LJj,Cei.j,0y Iy 2., prepared by aqueous method. valuevalues s oof f KyCe^yO^K."Ce)-y 02_. , prepareP民pared d bby y aqucous aqueouaqucous s method:method. ' ® ® CD © t 3.2 3.3.2 2 ReactioRcaction n of Ce0Cc02 2 witwilh h MOBu' (M=Li(M=Li,K，K) ) WheWhen n ththe e gaseougaseous s LiOBuLi OBu' 1 wawas s reactercacted d witwith h Ce0Ce02 iin n a y 0.023 0.055 0. 105 0.188 2 scalcd scalescalcd d tubetubc ,， a blacblack k compouncompound d wawas s producedproduced. . ResultResults s oof f X 0.020 0.067 0.170 0.348 X-raX-ray y diffractiodi 佑 action n analysianalysis s fofor r 白thiis s compouncompvund d aal t c1 elevate evaled d a(A) 5.4115 5.4117 5.4122 5.4138 temperatureIcmperalures s ararc e showshown n iin n FigurFi gurc e 44. . 百Thle e reactioreaction n timc time Tablc TablTablc e 2 J-y-,， x-valuex-valucs s anand d latticlatticc e parametepruameter r oof f CC _ 0 preparcd by aqucous metbod. Ky KyCc^yO,.1 y 2 鬼, prepared by aqueous method. LiOBu'-tCe0Li08u ・...CeOl 2 1173K II73K,， u. 12kr .rs s ® © ® © y 0.020 0.050 0.102 0.200 X 0.028 0.066 l_A K—Kt— 0.128 0.267 《-a a (A) 5.4112 5.4115 5.4118 5.4124 ・・ vh Li LiOBa'*Cc0OB.'. CeO l2 l073K 1073K,， 12~rs12kr s 5.415 5.415 LO.S “=・圃・ 5.414 5.414 O. ・ u' 冒岡 制" 5.413 0 _M IW NL-J^ l*A_AA_ 【 .均 0.3 0.3 ~ ・v4 Ol Ol u 5.412 5.412 J-、 0.2 凶 5.' 11 関 ・ 崎 5.41 5.41 10.1 健 JL JLl) ,-IU z。 -80 100 0.05 0.05 0.1 0.15 0.2 60 0.05 0.1 0.15 20 y i5D n LI UrCCLrO,.，. Cel_ ，. O:__ , Figure Figure X-ray diffraction pa 悦 ms for Li yCel_y02_x Figurc Figurc Figure 2 Relation Relation bctween between lauice lattice par parameter溜 neler ,， x andand y Figure 4 X-ray diffraction patterns for LLCe, O^, values values values ofof Li LiyCe,.,.^., yCC1_y02_x , preparcd prepared by by aqueous aqueous al_ at ele~aledelevated tempeiaturc temperature preparcd prepared byby -tiI th e ieaclion reaction mcthod. mcthod. method. of ofCeOjwithLiOBu'Ce02 with L1 0Bu'. . 164 waswa s fixcd fixed for for 12 12 hours. hours. Th e X-rayX-ra y diffraction diffraction pattems patterns ofof over over 12731273 K as as 田seeen n 泊in Figure Figure 5. 5. 百Thle e composition composition ofof 也the e as thc thc the ncwne w phascphase waswa s obscrvcdobserved for for thc the sampJcsampl e heatcd heated at at products products waswa s Ko Ko.o35^.oJsCe oo.9^^i.陥 0 1..7171 as given given in in Table Table3 3 from from about about about 973973K K. . Jt It waswa s sccn seen 出thaat t the th e intcnsity intensity ofof the the peaks peaks for for the the resu result1t s ofof chelllical chemical 3Il analyses alys i:s: . thc thc the ncwne w phasephase incrcased increased withwith incrcasing increasing temperature. temperature. Finally ,， tthl1 ce Ce02Ce0 2 phasc phase disappeared disappeared andand thc the ncwne w fluontc fluorite 3.3 3.3 Evaluation Evaluation of of oxygenoxygen 祖analysialys おs When a part of the oxygen of Ce0 is 田 moved forming phasc phasc phase waswa s in in a singlc single phasc phase abovcabove 11731173 K. K. Th e newne w phase phase When a part of the oxygen of Ce022 is removed forming Il waswa s formeformcd d within within aan n houhour r anand d !hc the Ce0 22 phasphase e disap- disap Ce0 2_x„' 也th.e e weight weight dαreasedecreas e ofof Ce0 22 duri during the the pr proces∞ ess s pcarcd pcarcd peared complctcly completely aafte白cr r 5 hour hours百.. is is 00.76wt.1 6Wt% % for for x=O.1 x=0.1 組and 0.07wt%0.07wt % for for x=Ox=0.01訓.百. Thelen n 曲thEe ThcTh e lattice lattice parameterparamctcrs of s of t"c the solid solid solutions，, analyti analytica叫叩l erroor r in i n determination determination ofof oxygenoxyge n content content seemsseems to be critical for the analysis of M Ce _..0 _ , the evalua fv!Mj.Cej.j.O,.):~~l づ O 2 -，, aar午前e givecn n in in Tablc Table 3. 3. TheTh e latticc lattice paramctcr parameter to be criti caJお E 曲E 組 alysis of MVCel_V02_x' y 1 2 I the evalua- onithiuIn onithiuIn of lithium cantaining containing ncwne w phase phase is is 55.493.4 937 7 X which which is is1. 1.55% % tion tion ofof oxygenoxyge n analysis analysis waswa s conducteo. conducted. TheTh e oxgenoxge n con-con 12 than than .4 百 伊 出E tents tents 泊K，.in Kj.CeCe j 02_x 02_x werewer e estinlated estimated byb y using using 也the di differ低 r- larger larger larger than that that ofof CcOCe02z(5.411(5 110 0 X)12). X) >. Thlcex e expansionsion n of of the 1叶 latlicc latlicc lattice parameter parameter secmsseems to to bebe causcd caused byby 由thec formation formation ofof enceence betweenbetwee n the the -calculated calculated value value andan d observed observed oneon e of of the mixture of potassium peroxide, K0 , and Cc0 . The solid solid solid solu.tio~~solution, LiyCc^yOj..,,~y~C_tc yÛ2~x ・. NoN o diffraction diffraction lines lines for for thc the the mixture of potassium peroxide ，K0 2 ，and Ce02 2・The f3 13 14 results of Tables 1 and 2 were corrected in Tables 4 and 5 compounds ,， Li sCe0 6 'f arid. and Li LiCeOj Ce0214) ) wewer聡e formed. formed. 百ThEe results of Tables 1 and 2 were ∞ rrected ln Tables 4 and 5 B 6 for LiyCe^yOj,, and KyCej^.O^,, respectively. composition composition composition of of thc the solid solid solution solution detcrmined determined is is givcn given in in for LiyCe1_y02 唱 and K， Ce1_y02_x ，respectively. Tablc TablcTable 3. 3. ThcTh e cxperimcntal experimental vaJuc value of of oxygcnoxyge n content content of of CC02Cc0 2 (18.58 (18.58 wt%)is wt%)is in in goodgoo d agrcc agreemen!!l cnt t with with the the calculat- calculat Table Table 4 y-value ,， corrccted correcte d x-value x-value 却an d latticc lattice pparamete副首nctcr r cd cd ed valuc value (18 (18.5.5 9 則的.wt%). ThcTh e chemical chemical formula formula of of 由the solid solid change change with. with y <<;， of Li LiyCe^.O^yCe トヲ 02_x , prepared prepared byb y solution is given as Li Ce O from the results of solution solution is givcn as Li O.044CCO.9560 0044 0956 1. 1662 2 from the results of aqueous aqueous method. method. chemical chemical chemica l analyses. analyses. Table Table Table 3 Chemical Chemical composition composition andan d lattice lattic e pararneter parameter ofof ® ® ® © MvCel_v02_x MvCel_v02_x Nl.CC] 02 , prepared prepared by by the the reaction reaction ofof y 0.023 0.055 0.105 0.188 Ce0CcQ2 with with MOBu'MOBu ' (M=(M=Li,K)Li， K). . X 0.019 0.096 0.175 0.372 Lattice 0 M Chernical Chemica l formula formula paraieter 8&/ 8y -0. 350 -0. 759 -0. 80S -0.857 (*tX) (A) Table Table Table 5 y-value ,，∞ correcte rrecled d x-value x-value 組an d lattice lattice paparamete型 neler r Li Li Llo o. . 11 D44Ceo.9fie044CeO . l . 6z 62 5.4937 l.i,Cei ,02 , 16.14 0.19 ~6& Ol change change change with with y ofof K. KyCe,_Ce 1_， 02_x y02_ s prepared prepared byb y K,Co, ,0* , 16.72 0.84 Ko. Ko. a3dCeO.03eCei? . tlnOl.pasOi . ，7 Ii 5. 4797 aqueous aqueous mcthod. method. . TheTh e rcation ication ofof CeOCe0， with wit h KOBu'KOBu " waswa s similar similar to to 出thaat t oof f 2 ® ® ® © CeOzCeO , with with Li LiOBu'OBu'.τ . Th1I e newne w X-rayX-ra y difl diffractio仕action n pattems patterns ofof singlc singlc phase which had a fluorite structurc were obtained single phase which had a fluorite structure were obtained y 0.020 0.050 0.102 0.200 X 0.052 0.090 0.155 0.294 KODu'+CeOl KODu'+CeOl <5a/5y -1.144 -0. 786 -0. 663 -0.641 1Z 73K ，Il hrs OnO n the the other other hand ,， the th e solid solid solutions solutions wercwer e synthc- synthe 百 由 加 疋 sized sized sized in in air. air. The valence valence statte e ofof ceriu m，n in MMyCe]_VCe 1_v0v022_ 5 should should should bebe +4. +4. ThenThe n the the x-valuex-value cancan be be calculated calculated bシy the the -〔・ charge charge neutra neutralit1i ty y condition. condition. TheTh e results results are are givengiven in in E Table!abl~ss 6~ andand 7 .for for LiyyCeCe,_\~y02y02_定組x and K， KyCej.yO^,Cel- yU 2-. ,， re~pe~respec ・聞〕 tively. tively. FromFro m these these iesu results1t s，, ithIi e oxygenoxyge n conte contentl1 ts s in in the the 'h KOBu'+CeOa aboveabove solid soli d solutions solutions werewer e calculated. calculated. 百Thle e differen difference∞ssbe- be 1l 73K ，IZb 目 tweentwee n the the estimated estimated andan d calculated calculated values values werewer e in in the the 細岨凶 range range range ofof O.03wt%0.03wt% ー- O.8wt%:0.8wt%: 官官The inert inert gas gas fus:o fusio n!l analy- analy EBA'E sis sis seemsseem s to to give give the the determined determined values values of of whichwhic h the the precision precision precision is is somewhatsomewha t insufficient insufficient as as the the oxygenoxyge n content of MyCej.yO^,. 岡 content of M uC y-....)-y'"'2-x. e，_..o I・73K ，IZh 町 Table Table 6 y-value ,， calculated calculate d x-value x-value andan d lattice lattice parameparamete町r KOBu'+CeOl KOBu'+CeOl chchang佃 ge e with with y of of Li LiyCej.yOj.yCe I-.o 2-x, prepared prepared ・:CeO ，pb ・・ e by by aqueous aqueous method: method. ® ® © © y 0.023 0.055 0.105 0.188 100 100 6・ X 0.019 0.096 0.195 0.372 2. 2.08 Figure Figure Figure 5i X-rayX-ra y di diffractiof:企 action n papattern位ems s for fotor K，. KyLe^U^KyCe^Ce 1_y0O2 _x, at at Sa/8y -0. 657 -0. 651 -0.653 -0. 646 clcvated clcvated elevated tempera temperatur伽 re e prepared prepared oy byv the.reaction the rereactio; n oof f with with KOBu'. 1 Ca0C~022 with KOBu . -~ 165 - Tahlc Tahlc Tabic 7 y-value ,， calculated calculate d x-value x-value andan d latticc lattice pramcter pramcter waswa s exposed exposed to to air ，, over ove r oneone day ，也, the 泊intensittensity y ofof di diffrac飴 ac- tion tion tion peaks peaks ofof the the newne w phase phase decreased ,， while whil e the the peaks peaks chang~hangce with with y t? of ~Cel_y02_xKyCe1_y02.] , prcparcd prepared for for for Ce02Ce0 phasc phase appappeared伺 red. . Th e peaks peaks ofof thc the solid soli d solution solution hy hyby aqucous aqueous mcthod. method. 2 disappe disappeare訂ed d over over 404 0 hhour(l urs s exposure exposure t10 o 託airr.ηle. The 鎚sammephe- e phe nomenonnomeno n waswa s observedobserved in in dried dried oxygcnoxyge n atmosphere. atmosphere. ® ® © © ThThes ese e facts facts showshow 由創出that the 也thisis solid soli d sclution solution is is susceptible susceptible to to to oxidation oxidation fornring forming stable stable CeCe00 22 r- phash笛 Ee 祖and inter-la inter-lattic凶ce e y 0.020 0.050 0.102 0.200 . Ii lithiuthiumby m by 血th e reaction reaction with with oxygen. oxygen. X 0.030 0.075 0.153 0.300 4. 4. 4. CONCLUSIONSCONCLUSION S 8 a. ' S y -0.660 -0. 654 -0. 654 -0. 654 1 百Thle e reaction reaction of of Ce02Ce0 2 with with MOBu'MOBu (M=(M=Li,KLi， K) ) waswa s studed studed ~sA s for. for tht!te~_~yCe MyCe,_ト pz-xy02_J prcPprepare!l r~dd b~by tht~ee _react~onreaction ofof with with the the aimai m to to fo forロmn newne w compcund.compound. Th e obtained obtaine d results results 1 Ce0 2 and and MOBu'MOBu ,， the th e corrected corrected chemical chemical formulas formulas are are showedshowe d that that noωmpoundno compoun d witb with differentαysdifferent crysta凶l s!ructure structure 判。 Ce 0 Li o0.o44.o o.9560i.70.956 1. 10 o and and Ko K00.03SCeO.96S0 35Ce096sO11. .18 78.・ TheThe values values ofof x waswa s formedforme d but but the the solid solid solution solution whichwhic h contains contain s alkali alkali obtained obtained obtained are are largcr larger thanthose than thos e ciblaIned obtained byb y thc the aqueous aqueous rnetal. metal,， M"CeL"O....y-::-l-y- MyCe^yO^ 今.:t , waswa s formed. formed. TheTh e conclusions conclusions ofof the the mcthod. mcthod. method . lt I t is i s considcred considered that tha t dissolution dissolution of o f alkali alkali mctal meta l iin n present present st studIl dy y are are summarizedsummarized as a s follows: follows: 1 Cc0Ce02 byb y the th e rcaction reaction with with MOBu'MOBu ' waswa s restricted restricted becau becaus民e 1l)Th )The e reaction reaction of of Ce0 22 with with MOBu'MOBu 民occurcurs s over over 11731173 K 1 of ofof thc the reducivc reducive condition condition causedcaused byb y thc th e carbarization carbarization for for Li LiOBuOBu' ' andand 12731273 K for for KOBu'KOBu formi formin目 .g g fluorite fluorite typc type reaction reaction reaction ofo f derivativcs derivatives of of alkoxides alkoxides comparedcompare d with with that that solid solution ，M，. Ce _ 0 _. ， which have larger lattice solid solution, MXej1 v022_„, which have larger lattice obtained by the aqueous method. obtaincd obtaincd hy the aqueous method. Pparameter嗣 meterss 伽tha~th;t~iC~Ö2n that of Ce62・. 2)The 2)The 2)Th e relations relations between between 出the y~va!uey-value andan d !attice lattice 伊pparametearame 目te 町r 町 33. .4 4 LaLatticttice e parametcr parameter change change ofof M.Ce1_v02_x MyCej.yOj..., 0or x-value x-value ぱ0offM MyCe1_y02., are linear. WhcnWhe n the the cxpansion expansion ofof lattice lattice parameter ,， a,， ddenrnd l' ['cnds s onon 巧33)Th)Th 恥echemice chemica伺al l fO formulaIm ulas s 0.ぱ oft f 白thhe e ssoli o. lid d solutions solutions are are 出c 'aluc x- and y-values ， a is cxpresscd by the follow- aB the 、value x- and y-values, a is expressed by the follow Li 1-10.044^0.95601.7O，044 Ce O.9珂 0) ，10 0 and ^ Ko， ^oxas^oses^i.n-035Ceu.9650 l.1 8・ ing ing in g rclation: relation: 4)The4)Th e lattice lattic e parinneters parameters ofof MVCe'_v02_x MyCej.yOj-, are are expressed expressed as as linear a linear linear combination combination of of lattiee lattice paparamete厄meter r of of Ce0 andand 6a 22 da latlice p釘宙neter changes with x and y. =ao+3o + 」L x+iLy(1) (1) lattice parameter changes with x and y. 6x oy 5)The solid solution is oxi 抱 edω 白 O by prolonged aお 8y 5)The solid solution is oxidized to Ce022 by prolonged air oxidation. oxidation. oxidation. whwher c: rc e 30 3Q is is thc th e lattice lattice parametcr parameter of of Ce02' Ce02, o8a/5a/ ox x 釦and Oa!oy Oa!oy 6a/6y are ar e lattice lattice parameter parameter changes changes with wit h -x x and and y，, respe- respe References References ctively. ctively. ctively. 1. 1. Bradley ,， D.D.C. C.， , Mehrotra ,， R.C. R.C . and and Gaur ,， D.D . P.: P.: Metal Metal ln ln In the the 白casse e ofLof LiyCe,_九Ce1_VOz_x y02_,,，, the the values values ofof a,， x and and y in in AlkAlkoxideoxide ，, ο978)(1978)，, 46 ，, AcademicAcademi c Pr Press ess. . Tablc Tablc Table 5 andand a =5.4112 =5.4112 HoiX for eeO? Ce02 are are subslituted substituted into into the the 2. 2. Bains ，, M.M . S.: S.: 白Canadianadian n J. J. Chem.,，全~ 42 (1964) ，, 945945. . eqation eqation eqation (1). (1). TheTh e value value of of -0-0.4.4 4 as as oa!Ox 6a/5x for for Ce0 2 ob-ob 3. 3. Dunn ,， H.H . W.: W: ORNLORN L Report ,，盟盟 2092 (195 (1956)の， , 3838. . 旬taineined d 加from the the Ii linea ncar r rclation relation of of latticc lattice constant constant bebetweetW een n 4. Panlener ， R. J. ，Blumenthal ， R. H.and Gamier ，J. E.: J. 15 4. Panlener, R. J., Blumenthal, R. H.and Gamier, J. E.: J. cubic cubic cubic Ce z0 2033 (1 (11.21. 26 6 :¥)15) X) ) 叩and CC02Ce0 2 is is also als o substituted substituted into into Phys. Phys. Chem.Chem . SoSolidslids ，, 363 6 (1975) ，, 12131213. . this this equation. equation. Th ce obtained obtained valucs values of of oa/6a/ Oy6 y wcrcwere varied varied 5. 5. SS(|>rensen中rensen ，, O.O . T.: T. : J. J. Solid'StateChem. Solid State Chem.,， 1818 (1 (1976)976) ，, 217. 217. fromfro m -0.35-0.35 for for y=0.023y=0.02 3 10 to -0.86-0.86 for for y=0.188. y=0.188. OnO n the the 6. 6. Campserveux ,， J. J. 釦anddG Gardanian紅白nian ,， P.: P. : J. J. Chem.Chem. 百Thermo1巴rmo- - other other other hand ,， lattice lattic e parameter parameter changechange with with y werewer e also also dyn. dyn.,6(1974),795，Q (1974) ， 795. . calculated as given in Table 6 by using the data in Table 6. calculated calculated as given m Table 6 by using the da 包泊Table 6. 7. 7. RaRayy， , S. S. P. ，, Nowick ,， A.A . S. S. 釦and Cox ，, D. D . E.: E. : J. J. SoSoli lid d State State 百Th le e difference difference hetween between 出die two two sets sets ofof values values are are increas- increas Chcm.Chem.,，堕 15 (1975) ，, 344. 344. iinl! g at at the the lowlo w y-values. y-values. ThisThis mightmigh t bebe casusedcasused byb y the the 8. Faber ，J. Jr. ，Seits ，M. A. and Mueller ，M. H.: J. Pbys. limitation of oxygen analysis. 8. Faber, J. Jr., Seits, M. A. and Mueller, M. H.: J. Phys. limitation limitation of oxygen analysis. Chem.Chem . Solids ，笠, 37 (1976) ，明, 9033. . ト In In In the the casecase ofof K.CeKyCe1_v02_. y02.x,， the the lattice lattice parameter parameter 9. 9. Tuller ,， H.H . L. L. andand NNowicko. wiek ,， A. A . S.: S. : J. J . Electrochem. Electrochem. Soc. ，, changes changes changes with with y obtained obtained byb y ususini.t: ig g experimental experimental and and ccalcua¥ cu- 旦昼(1126 (1979)979) ，. 209. 209. l 166 .