高等学校化学学报Issue(7)：1395-1402,8.DOI:10.7503/cjcu20141004
La（NO3）3和Pr（NO3）3对高岭石脱羟基动力学的影响
Effect of La(NO3) 3 and Pr(NO3) 3 on Kinetic of Dehydroxylation of Kaolinite†
摘要
Abstract
The thermal decomposition processes of kaolinite mixed with La( NO3 ) 3 and Pr( NO3 ) 3 were inves-tigated by thermogravimetric analysis/differential thermal analysis ( TG/DTA ) simultaneous thermal analysis technique under different heating rates. Thermal analysis data were used for dynamic analysis by the Coats-Redfern integral method and Achar differential method to calculate the kinetic model function, activation ener-gy and pre-exponential factor of dehydroxylation process of kaolinite. The effects of two kinds of rare earth on kinetic parameters of dehydroxylation process of kaolinite were analyzed. The activation energy was validated by Ozawa method. The results show that dehydroxylation of kaolinite and the sample mixed with Pr( NO3 ) 3 are controlled by the rate of third-order chemical reaction ( F3 ) , the activation energies are 307. 94 and 282. 86 kJ/mol, respectively, and the values of pre-exponential factor lnA are 47. 8980 and 44. 1718, respectively;the kinetic model function of sample mixed with La ( NO3 ) 3 changes to the second-order chemical reaction (F2), the activation energy is 196. 02 kJ/mol, and the value of pre-exponential factor lnA is 29. 5551. Compared with the kaolinite without rare earth, the activation energy and the pre-exponential factor lnA of the sample mixed with Pr(NO3)3 have slightly reduced, while those of the sample mixed with La(NO3)3 signifi-cantly decrease by 36. 34% and 38. 30%, respectively. The value of the activation energy obtained by Coats-Redfern and Achar method is consistent with the one obtained by Ozawa method.关键词
La(NO3)3/Pr(NO3)3/高岭石/脱羟基过程/活化能Key words
La(NO3)3/Pr(NO3)3/Kaolinite/Dehydroxylation process/Activation energy分类
化学化工引用本文复制引用
匡敬忠,原伟泉,徐力勇,李琳,黄震..La（NO3）3和Pr（NO3）3对高岭石脱羟基动力学的影响[J].高等学校化学学报,2015,(7):1395-1402,8.基金项目
国家自然科学基金(批准号:51264009)和江西省自然科学基金(批准号:20122BAB206023)资助.@@@@?Supported by the National Natural Science Foundation of China(No.51264009) and the Natural Science Foundation of Jiangxi Province of China(No.20122BAB206023) （批准号:51264009）
