氯化铵氯化氧化镧(铈)的反应过程及其动力学

Kinetics on Chlorination Process of La_2O_3 and CeO_2 by Ammonium Chloride

通过考察反应温度、时间、氯化铵用量对氧化镧(铈)氯化的影响及氯化镧(氯化铈)结晶水合物的热解行为,研究了氯化铵氯化氧化镧(铈)的反应过程及其动力学.结果表明,在氯化的温度范围,既有氯化铵直接参与的氯化反应发生,又有氯化铵热解产物HCl使稀土氧化物氯化的反应存在.氯化镧(氯化铈)发生气相水解或氧化反应生成LaOCl,CeOCl,CeO2.氧化镧(铈)氯化反应的表观活化能Ea分别为43.73和140.67kJ/mol,过程限制环节是界面化学反应控制.

Using ammonium chloride (NH4Cl) as a chlorinating agent, the effects of chlorinating temperature, time and NH4Cl dosage on chlorination of La2O3 and CeO2, and the thermal decomposition of LaCl37H2O and CeCl37H2O were examined. The results show that NH4Cl directly participates the chlorination reaction, and HCl from pyrolysis of NH4Cl also contributes to the chlorination reaction. CeCl3 and LaCl3 can cause gas phase hydrosols formation or oxidation reaction which generates LaOCl, CeOCl and CeO2. The apparent activation energies of La2O3 and CeO2 chlorination reactions, Ea, are 43.73 and 140.67 kJ/mol respectively. The process is mainly controlled by the interfacial chemical reaction.