Rare earth oxide-catalysed decomposition of calcium oxalate

被引:7
作者
Bose, S [1 ]
Sahu, KK [1 ]
Bhatta, D [1 ]
机构
[1] UTKAL UNIV,DEPT CHEM,BHUBANESWAR 751004,ORISSA,INDIA
关键词
calcium oxalate; catalyst; rare earth oxides (REOs); thermal decomposition;
D O I
10.1016/0040-6031(95)02514-6
中图分类号
O414.1 [热力学];
学科分类号
摘要
The catalytic activity of rare earth oxides (REOs) on the isothermal decomposition of calcium oxalate has been studied within the temperature range 693-733 K. The fractional decomposition, alpha, versus time, t, plots for pure salt as well as for mixtures suggest that the process occurs through initial gas evolution, acceleratory and decay stages. Analysing the data in the light of theories of various kinetic models, it is indicated that the two-dimensional phase boundary reaction model gives the best fit of the results. Admixtures enhance the rate of reaction and decrease the energy of activation of both acceleratory and decay stages, the catalytic activity being in the order: La2O3 > Sm2O3 > Gd2O3. A plausible mechanism of decomposition and the role of the catalyst in the process have been discussed.
引用
收藏
页码:175 / 183
页数:9
相关论文
共 18 条
[1]  
BASAHEL SN, 1987, RADIAT PHYS CHEM, V29, P447
[2]   POSSIBLE HIGH-TC SUPERCONDUCTIVITY IN THE BA-LA-CU-O SYSTEM [J].
BEDNORZ, JG ;
MULLER, KA .
ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER, 1986, 64 (02) :189-193
[3]  
BHATTAMISRA SD, 1976, RADIAT EFF DEFECT S, V29, P41, DOI 10.1080/00337577608233482
[4]  
BOSE S, 1994, INDIAN J CHEM A, V33, P230
[5]  
BOSE S, 1994, IN PRESS J THERM ANA
[6]  
CORDES HF, 1974, J PHYS CHEM-US, V78, P768
[7]   THE THERMAL-DECOMPOSITION OF OXALATES - A REVIEW [J].
DOLLIMORE, D .
THERMOCHIMICA ACTA, 1987, 117 :331-363
[8]  
Dollimore D., 1970, J THERMAL ANAL, V2, P229, DOI [10.1007/bf01911405, DOI 10.1007/BF01911405]
[9]   THE THERMAL DECOMPOSITION OF POTASSIUM PERCHLORATE AND PERCHLORATE HALOGENIDE MIXTURES - A STUDY IN THE PYROLYSIS OF SOLIDS [J].
GLASNER, A ;
WEIDENFELD, L .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1952, 74 (10) :2467-2472
[10]   THE THERMAL-DECOMPOSITION TEMPERATURES OF IONIC METAL OXALATES [J].
KAHWA, IA ;
MULOKOZI, AM .
JOURNAL OF THERMAL ANALYSIS, 1981, 22 (01) :61-65