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Study of thermal properties of new compounds containing formates op alkali and rare earth elements
ThermochimicaActa, 92 (1985) SOS-508 Elsevier Science PublishersB.V., Amstedam STUDYOFTHNRMAL PROPl&tTIBSOFNEWCOMRXJNDS FORMATES OF ALKALIANDRAREEARTH~S
COH%IlU.NG
S.M.Portilova, E.V.Petrova, I.B.Kudinov,N.K.Semendyaeva, V.F.Ryurikov Kurnekov's Institute of General and Inorganic Chemistry Academy of Sciences, MOBCOW, DSSR
ABSTRACT DTA, DTG and DSC defined phase transformationte eratures 3 0; and heats of following compounds: LiHCOO*(l-2)NaHCOO' LiHCOO*KHCOO;LiHCOO*RbHCOO*0,5H0; LiHCOO.CeH7000 , JjeHC80.2,51(ACOo Na[Y(HCOO) H 01 H 0; K [Y(HCOOf H 01; K [Y HCOO 3. We established4co$rela?ionbetween t&e&l pr%pertiee 8( T, and AH) and the nature of structure of compounda.
INTRODUCTION Nowadays there exists exteneive literature on study of thermal properties of simple formates. We have istudiedthehal properties of a number of complex fofm&tes of the 3'ollowing formula: LiHCOO*(l-2)aaHCO03H20; LiHCOO~KHCOO;MJiCOO*RbHCOO* *0,5H20;LiHCOO*CsHC60;NeHCb0~2,5KHCCO;Na[Y(HCOO)4 ~20]H20; X [Y(HCOO)4 H20] ; K5 [ Y(HC00f8]. We obtained these phaeea in the course of investigationof correspondingwater-salt syetern6[l-7]. The abovementionedcompounds were identified by means of IR spectroscopy,X-ray difraction and crystal-optic method. Structures were defined for complex compounds on the basis of Yttrium formate [8]. EXPERWENTAL The study of thermal stability of compounds was carried out by the methods: DTA - on PRT-1OOOM; DTG by Paulik-Erdey derivatographwith temperature programatorLP-980 and Q-derivatograph MOM ( the heating rate - 5'/min, mass of sample approximately Ig). The heats of dehydration,melting and thermal decompositionwere defined by differential acanning calorimeters of the Du Pont - 990 and Mettler TA - 2000 type. Scanning rate Proceedingsof ICTA 85, Bratislava
-
506
-
ie 2-lO'/min,ma88 of sample from 2 to 20 mg, reference- A1203. The experiment was made in the air as well as in inert gases. The enthalpy was defined according to the programme " Peak Integration"on lettler TA - 2000. The enthalpy on Du Pont- 990 was calculated by formula: bO.E*aq,+) M , A - area of-the peak (sm'), m- ma88 of sample, reverse value from rate of paper-strip movement, BAq,- sensitivity (mv/sm), M- molecular mass.
AH = +(
where
RESULTS AND DISCUSSION All data obtained are shown in tables l-3. Alkali metals double formates
- 507 decrease melting and decompositiontemperature in Y(HC00)3*2H20 (I) - Ha[ Y(HCOO)4 F120]H20 (II) - K [Y(HC00)4 K20](111) K5 [kT(HCOWS] (Iv). Table 2. DTA, DTG and DSC results of dehydration process. Atmos Loss of 'phere ' Melting I mass,% : 3 temperature,:heat, : K kJfmole4theor:exl, ________~~~~~_~__~~_~_~_+__~__________~___ ---_- ""__""'n~~ra t gen :*167 + 3 : - :LiHCOO*(l-2)NaHCOO*nH20: 361-366 Compound
’ Melting
Y (HC00)3'2H20
' 383-418 : 418-431
Na [Y(HCOO)4 H20] H20
: 345-356 : 356-358
K [Y(HCOOj4 H20]
: 355-366 : 366-378
: :
24 + 2 : '4,03: 28 + 2 ~'~*~~f&j&: air : , ’ air : 5,29+0,1* * 3,8qtO,i' 5,Pi: 6,Ognitro :gen nitro t *34,57$*1; :13,41+0,1,5,52: 5,2Ag;;r
* dehydration heat is given in J/G Table 3. Melting and decompositiontemperatures of compounds on the basis of Yttrium formate. Compound : Melting Decomposition temperature K ____________________~~~~~~~~~ ______cr_______~___4~9_eratu;f_erK_, Y(HC00)3'2H20 Na [Y(HCOO)4 Ii201H20 K[Y(HC00)4 H20] K5[Y(HCOOJ8]
: :
: :
603 583 558 493
: I t
648 638 633
f
Str+e&mres II and III are polymeric, layered with independent formate groups, having different conformation structure and dentate %w. However, the character of structures II end III has much $.stmnw with structure of Y(HC00)3*2H20,whereas structure IV 9s IseXated, ionic. All formate radicals are monodentate. ~Fbe structure of this compound is an analogue of that of the origtil Potassium formate, the melting temperature of
- 508 with is 439K, that is, 164K lower than melting temperature of Y(HCOO)3*ZH20.The melting temperature of IV is lower than those of II and III, accordingly. REFERENCES 1 S,M.Portnova,L.S.Itkina, J.Neorg.Chim. 2 (1979) 213 2 L.S.Itkina,N.M.Chapligina,E.V.Petrova, 4 .Neorg.Chlm.2 (1979) 788 3 L.S.Itkina, E.V.Petrova, J.Neorg.Chim.A 2 (1979) 1103 4 L.S.Itkina, E.V.Petrova,J.Neorg.Chim. (1982) 517 5 E.V.Petrova, S.M.Portnova,L.S.Itkina, . .Schurkina, J.Neorg.Chim. 26 (1981) 3121 6 L.S.Itkina, (1981) 3112 E.%Petrova, A.S.Antsishkina,J.Neorg.Chim.26 7 S.M.Portnova,E.V.Petrova,A.K.Lyascenko,I.N.Lepeshkov, J.Neorg.Chim.28 (1983) 2952 8 A.S.Antsishkina,M.A.Poray-Koshita,V.N.Ostrikdva,E.V.Petrova, Koord.Chimiya2 (1983) 986 9 A.S.Antsishkina,M.A.Poray-Koshits,I.V.Arhengelskiy, L.A.Butman, Koord.Chimiya1 (1976) 565
COH%IlU.NG
S.M.Portilova, E.V.Petrova, I.B.Kudinov,N.K.Semendyaeva, V.F.Ryurikov Kurnekov's Institute of General and Inorganic Chemistry Academy of Sciences, MOBCOW, DSSR
ABSTRACT DTA, DTG and DSC defined phase transformationte eratures 3 0; and heats of following compounds: LiHCOO*(l-2)NaHCOO' LiHCOO*KHCOO;LiHCOO*RbHCOO*0,5H0; LiHCOO.CeH7000 , JjeHC80.2,51(ACOo Na[Y(HCOO) H 01 H 0; K [Y(HCOOf H 01; K [Y HCOO 3. We established4co$rela?ionbetween t&e&l pr%pertiee 8( T, and AH) and the nature of structure of compounda.
INTRODUCTION Nowadays there exists exteneive literature on study of thermal properties of simple formates. We have istudiedthehal properties of a number of complex fofm&tes of the 3'ollowing formula: LiHCOO*(l-2)aaHCO03H20; LiHCOO~KHCOO;MJiCOO*RbHCOO* *0,5H20;LiHCOO*CsHC60;NeHCb0~2,5KHCCO;Na[Y(HCOO)4 ~20]H20; X [Y(HCOO)4 H20] ; K5 [ Y(HC00f8]. We obtained these phaeea in the course of investigationof correspondingwater-salt syetern6[l-7]. The abovementionedcompounds were identified by means of IR spectroscopy,X-ray difraction and crystal-optic method. Structures were defined for complex compounds on the basis of Yttrium formate [8]. EXPERWENTAL The study of thermal stability of compounds was carried out by the methods: DTA - on PRT-1OOOM; DTG by Paulik-Erdey derivatographwith temperature programatorLP-980 and Q-derivatograph MOM ( the heating rate - 5'/min, mass of sample approximately Ig). The heats of dehydration,melting and thermal decompositionwere defined by differential acanning calorimeters of the Du Pont - 990 and Mettler TA - 2000 type. Scanning rate Proceedingsof ICTA 85, Bratislava
-
506
-
ie 2-lO'/min,ma88 of sample from 2 to 20 mg, reference- A1203. The experiment was made in the air as well as in inert gases. The enthalpy was defined according to the programme " Peak Integration"on lettler TA - 2000. The enthalpy on Du Pont- 990 was calculated by formula: bO.E*aq,+) M , A - area of-the peak (sm'), m- ma88 of sample, reverse value from rate of paper-strip movement, BAq,- sensitivity (mv/sm), M- molecular mass.
AH = +(
where
RESULTS AND DISCUSSION All data obtained are shown in tables l-3. Alkali metals double formates
- 507 decrease melting and decompositiontemperature in Y(HC00)3*2H20 (I) - Ha[ Y(HCOO)4 F120]H20 (II) - K [Y(HC00)4 K20](111) K5 [kT(HCOWS] (Iv). Table 2. DTA, DTG and DSC results of dehydration process. Atmos Loss of 'phere ' Melting I mass,% : 3 temperature,:heat, : K kJfmole4theor:exl, ________~~~~~_~__~~_~_~_+__~__________~___ ---_- ""__""'n~~ra t gen :*167 + 3 : - :LiHCOO*(l-2)NaHCOO*nH20: 361-366 Compound
’ Melting
Y (HC00)3'2H20
' 383-418 : 418-431
Na [Y(HCOO)4 H20] H20
: 345-356 : 356-358
K [Y(HCOOj4 H20]
: 355-366 : 366-378
: :
24 + 2 : '4,03: 28 + 2 ~'~*~~f&j&: air : , ’ air : 5,29+0,1* * 3,8qtO,i' 5,Pi: 6,Ognitro :gen nitro t *34,57$*1; :13,41+0,1,5,52: 5,2Ag;;r
* dehydration heat is given in J/G Table 3. Melting and decompositiontemperatures of compounds on the basis of Yttrium formate. Compound : Melting Decomposition temperature K ____________________~~~~~~~~~ ______cr_______~___4~9_eratu;f_erK_, Y(HC00)3'2H20 Na [Y(HCOO)4 Ii201H20 K[Y(HC00)4 H20] K5[Y(HCOOJ8]
: :
: :
603 583 558 493
: I t
648 638 633
f
Str+e&mres II and III are polymeric, layered with independent formate groups, having different conformation structure and dentate %w. However, the character of structures II end III has much $.stmnw with structure of Y(HC00)3*2H20,whereas structure IV 9s IseXated, ionic. All formate radicals are monodentate. ~Fbe structure of this compound is an analogue of that of the origtil Potassium formate, the melting temperature of
- 508 with is 439K, that is, 164K lower than melting temperature of Y(HCOO)3*ZH20.The melting temperature of IV is lower than those of II and III, accordingly. REFERENCES 1 S,M.Portnova,L.S.Itkina, J.Neorg.Chim. 2 (1979) 213 2 L.S.Itkina,N.M.Chapligina,E.V.Petrova, 4 .Neorg.Chlm.2 (1979) 788 3 L.S.Itkina, E.V.Petrova, J.Neorg.Chim.A 2 (1979) 1103 4 L.S.Itkina, E.V.Petrova,J.Neorg.Chim. (1982) 517 5 E.V.Petrova, S.M.Portnova,L.S.Itkina, . .Schurkina, J.Neorg.Chim. 26 (1981) 3121 6 L.S.Itkina, (1981) 3112 E.%Petrova, A.S.Antsishkina,J.Neorg.Chim.26 7 S.M.Portnova,E.V.Petrova,A.K.Lyascenko,I.N.Lepeshkov, J.Neorg.Chim.28 (1983) 2952 8 A.S.Antsishkina,M.A.Poray-Koshita,V.N.Ostrikdva,E.V.Petrova, Koord.Chimiya2 (1983) 986 9 A.S.Antsishkina,M.A.Poray-Koshits,I.V.Arhengelskiy, L.A.Butman, Koord.Chimiya1 (1976) 565