乙烯氧氯化反应技术的研究Ⅱ．反应历程及动力学

Studies on Ethylene OxychlorinationⅡ. Reaction Mechanism and Kinetics

以ＣｕＣｌ＿２／Ａｌ＿２Ｏ＿３为催化剂，在２１１—２５１℃内，研究了近似工业反应器内反应气氛变化条件下的乙烯氧氯化反应机理及动力学。提出了吸附－氧化还原反应机理，合理地解释了试验现象，利用平衡态近似法推得了相应的动力学机理方程式，得到了试验数据的验证。对试验结果的进一步处理发现，该催化剂在反应温度升至２３３℃左右，反应活化能有一突降现象，并首次指出其原因可能是该催化剂在制备方法上的不同所致。最终还求得了简明、实用的幂函数速率方程式。在本试验温度范围内，该式的计算值和试验值的总平均相对误差均小于５．５％。

The mechanism and intrinsic kinetics of the heterogeneous gas-phase oxychlorination ofethylene to 1,2-dichloroethane(EDC)were investigated in a differential fixed-bed reactorby using CuCl_2/Al_2O_3 as the catalyst and under the reaction atmosphere simulating that ofthe commercial reactor.The temperature range was 211-251℃. An adsorption- redox mecha- nism was proposed on the basis of our experimental results. The experimental phenomenawere reasonably explained and a mechanismic kinetic equation was obtained in the form of The results show that the reaction rate increases with the increase in partial pressuresof ethylene and oxygen;it is independentl however,of the partial pressure of hydrogenchloride,It was also found that the reactive activation energy fell suddenly when the tem- perature rose to about 233℃. This is because of the differences in manufacturing method ofthis catalyst. The experimental data could finally be experessed in the form of a power- lawequation The models fit the experimental data with an average deviation of 5.5%. r′=1.2127× 10￣9exp(-94.671 × 10￣3/RT)