含氮合成气直接合成二甲醚复合催化剂与混合催化剂性能及本征动力学  

Study on Properties and Intrinsic Kinetics of Mixed and Hybrid Catalysts for Direct Dimethyl Ether Synthesis from Synthesis Gas Containing N_2

作　　者：刘宏伟[1] 刘殿华[1] 应卫勇[1] 房鼎业[1] 

机构地区：[1]华东理工大学化学工程系,上海200237

出　　处：《高校化学工程学报》2005年第1期59-64,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：上海市重点学科建设项目。

摘　　要：在直流流动等温积分反应器中,反应压力3.0～7.0MPa、温度220～260℃及空速500～2000 mL·g-1·h-1下,研究了含氮合成气直接合成二甲醚双功能复合型催化剂和混合型催化剂的催化性能.实验结果表明在两种不同双功能催化剂上,240℃、7.0 Mpa及1000 mL·g-1·h-1是较好的反应条件,复合型催化剂与混合催化剂反应性能相近,反应温度较高时复合催化剂二甲醚选择性基本保持不变,而混合型催化剂二甲醚选择性随温度升高降低.在复合催化剂上进行了含氮合成气合成二甲醚本征动力学研究,选用了双曲型动力学模型,采用遗传算法与单纯型算法相结合的方法对模型参数进行估值,获得了模型参数,比较了混合催化剂、复合催化剂上合成二甲醚的反应速率.The direct dimethyl ether synthesis from synthesis gas containing N2 was investigated in a fixed-bed reactor on two kinds of bifunctional catalysts in the range of temperature 220-260°C, pressure 3.0-7.0 MPa and space velocity 500-2000 mL&middotg-1&middoth-1. The results show that the conversion of CO is increased with the increasing reaction temperature on both catalysts, the selectivity of DME doesn't changed dramatically on hybrid catalyst, but decreased slightly on mixed catalyst. Higher CO conversion is obtained when higher reaction pressure is used. When at 240°C, 7.0 MPa and 1000 mL&middotg-1&middoth-1, CO conversion was 92.42% and DME selectivity was 86.65% on hybrid catalyst. Then the intrinsic kinetic model on hybrid catalyst was studied. The parameters of the L-H kinetics model were obtained by using simplex method combined with genetic algorithm. The reaction rates of CO hydrogenation, CO2 hydrogenation and methanol dehydration on hybrid catalyst were calculated and compared with those of mixed catalysts. The results indicate that numerical values of parameters on two kinds of catalyst are close to each other, and the reaction rate of hybrid catalyst is slightly higher than that of the mixed one. The same active component on the two kinds of catalysts results in similar catalytic properties.

关 键 词：二甲醚 合成气 双功能催化剂 固定床反应器 本征动力学 

分 类 号：O64338[理学—物理化学] TQ426.83[理学—化学]