反应压力对正丁烯骨架异构催化剂反应性能的影响

Effect of Reaction Pressure on the Performance of Catalyst in n-Butene Isomerization Reaction

采用Aspen plus软件,计算得到了正丁烯异构化反应产物组成随反应压力变化的规律,同时以镁碱沸石为催化剂,在固定床小试评价装置上考察了反应压力在不同反应阶段对催化性能的影响。结果表明,在异构化反应初期,提高反应压力,正丁烯转化率增加,异丁烯选择性下降,异丁烯收率变化较小;而在催化剂运行后期,反应压力从常压提高到0.05MPa,异丁烯选择性变化不大,而异丁烯的收率却提高了2～3百分点。这可能是由于在异构化反应进行过程中,由于催化剂酸性质的变化,反应也经历了从双分子反应机理为主,到以单分子反应机理为主的转变,因此反应压力对催化剂性能的影响也随之改变。

Aspen plus software was used to calculate the correlation between reaction pressure and product composition in n-butene isomerization process,which was operated in a fixed bed reactor by using ferrierite catalyst.The effects of reaction pressure on the catalytic performance in different reaction stages were investigated respectively.Results indicate that in the initial stage of the reaction,the conversion of n-butene is increasing with the increase of reaction pressure,but the selectivity of isobutene shows opposite trend,while isobutene yield changes little.In the later stage of the reaction,with the increase of pressure from atmosphere to 0.05 MPa,the selectivity of isobutene is changed little,but the yield of isobutene increases by 2-3 percentage.The reason is explained that with the change of catalyst acidity in the isomerization process,the reaction mechanism also becomes changed from mainly bimolecular pathway to unimolecular pathway.Therefore,the effect of reaction pressure on the catalytic performance is changed accordingly.