氯化铵氯化氧化镧氧化铈混合物及其动力学

Chlorinating reaction of the admixture of La_2O_3 and CeO_2 by ammonium chloride and its kinetics

研究了氯化铵氯化氧化镧氧化铈混合物的适宜条件及其氯化反应动力学 研究表明:在氯化铵用量为nNH4Cl/n(La2O3+CeO2) =12∶1的物质的量比、氯化焙烧温度 390~400℃、氯化时间 25min的条件下,稀土的氯化率在 80%以上;氧化镧与氧化铈混合物的氯化反应动力学遵从Erofeev方程,氯化反应的表观活化能Ea为 13. 49kJ·mol-1,动力学方程为k=1. 6e-13490 /RT,属于内扩散控制 CeO2 与NH4Cl的反应是混合氧化稀土氯化的控速步骤,反应程度决定混合氧化稀土氯化率的大小 混合氧化稀土的组成与配分。

This article analysize the optimum conditions and response-chlorinating kinetics of chlorinating with ammonium chloride in the admixture of La_2O_3 and CeO_2. On the condition of the following terms:25 min of Chlorinating the admixture of La_2O_3 and CeO_2 ,with ammonium chloride dosage n_(NH_4Cl)/n_((La_2O_3+CeO_2))=12∶1 at 390～400 ℃; the chlorinating ratio of the mixed rare earth oxides reaches 80%.The reaction rate equation followed the Erofeev equation ln[-ln(1-α)]=lnk+nlnt,and the functional relation between the reaction rate constant and temperature can be described as k =1.6e^(-13490/RT),the apparent activation energy Ea is 13.49 kJ·mol^(-1). The process was mainly controlled by the internal diffusion contro.The response and response degree of CeO_2and NH_4Cl are dividually the speed-controlled process which is chlorided the mixed rareearth oxides and the key which is dertermined chlorinating ratio of the mixed rare earth oxides.When the mixed rare earth oxides is chloratde,the components and partition of the rare earth is an important factor for the chlorate ratio and reaction rate.