十水草酸铈的热分解过程以及热分解动力学研究  

Thermal Decomposition Process and Kinetics of Cerium Oxalate Decahydrate

作　　者：苑斯雯 杨金月 周冠辰 谢非 黄云海 田贝倩 吴德慧 侯学锋 黄欣 郝红勋 Yuan Siwen;Yang Jinyue;Zhou Guanchen;Xie Fei;Huang Yunhai;Tian Beiqian;Wu Dehui;Hou Xuefeng;Huang Xin;Hao Hongxun(China Nuclear Power Engineering Co.,Ltd.,Beijing 100840,China;National Engineering Research Center of Industrial Crystallization Technology,School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin 300072,China)

机构地区：[1]中国核电工程有限公司,北京100840 [2]天津大学化工学院国家工业结晶工程技术研究中心,天津300072 [3]天津化学化工协同创新中心,天津300072

出　　处：《化学工业与工程》2021年第4期1-12,共12页Chemical Industry and Engineering

基　　金：天津市自然科学基金(18JCYBJC40800)。

摘　　要：利用TG-DSC法研究了十水草酸铈在N_(2)和O_(2)氛围下煅烧过程的差异及其分解动力学机理。结果表明,十水草酸铈在N_(2)气氛下煅烧时,煅烧产物CeO_(2)表面附着有黑色的炭黑,而在O_(2)气氛下煅烧时,仅得到浅黄色的CeO_(2)。依据实验结果推测,十水草酸铈在N_(2)气氛下煅烧时经历3步热分解过程;而在O_(2)气氛下煅烧时经历2步分解过程,第1步为十水草酸铈脱去十分子结晶水生成无水草酸铈,第2步为无水草酸铈氧化分解为CeO_(2)。最后,对十水草酸铈在O_(2)气氛下煅烧时的2步热分解动力学机理进行了研究。结果表明,第1阶段脱水过程的活化能在53.50~65.63 kJ·mol^(-1)之间,第2段氧化分解过程的活化能约为156.52 kJ·mol^(-1)。十水草酸铈热分解过程以及热分解动力学的探究能够为其后续煅烧制备CeO_(2)提供重要的热力学数据。The differences of thermal decomposition of cerium oxalate decahydrate under N_(2) and O_(2) atmosphere were investigated and compared by performing TG-DSC in this work. The results indicated that under N_(2) atmosphere,black elemental carbon would deposit on the surface of CeO_(2). While under O_(2) atmosphere,the calcined product was pale yellow,which was the color of CeO_(2). The thermal decomposition process of cerium oxalate decahydrate under N_(2) would go through three stages. Two processes would occur under O_(2) atmosphere,the first process is the dehydration of cerium oxalate decahyrate;the second process is the decomposition of anhydrous cerium oxalate. The thermal decomposition mechanisms of cerium oxalate decahyrate under O_(2) atmosphere were also studied. The activation energy for the first stage (dehydration process) was between 53. 50 and 65. 63 kJ·mol^(-1),and the activation energy for the second stage was 156. 52 kJ·mol-1. The research on the thermal decomposition process and kinetics of cerium oxalate dehydrate could provide a crucial theoretical basis for the preparation of CeO_(2).

关 键 词：十水草酸铈 TG-DSC 热分解过程 热分解动力学 

分 类 号：O642.3[理学—物理化学]