多级孔HZSM-5催化环己烯水合制环己醇

Hydration of cyclohexene to cyclohexanol catalyzed by hierarchical HZSM-5

环己醇是生产尼龙6和尼龙66的关键中间体,其主要生产工艺为环己烯水合法,面临环己烯单程转化率较低(小于10%)的困扰。通过催化剂改性来提高环己烯单程转化率是一种经济有效的方法。本文通过碱溶液脱硅的后处理方法构筑了多级孔HZSM-5分子筛,详细考察了碱种类、碱浓度、处理温度和处理时间等对HZSM-5分子筛催化剂物化性质和环己烯水合反应性能的影响。实验结果表明:0.4 mol/L NaOH在323 K下处理3 h所得HZSM-5分子筛催化剂催化效果最优,环己烯单程转化率可达12.98%;表征结果表明HZSM-5分子筛催化性能的提高是传质过程强化和催化剂表面适宜酸性质两方面因素的综合结果。

Cyclohexanol is an important chemical intermediate for the production of nylon 6 and nylon 66.As the main production process of cyclohexanol,the cyclohexene hydration process is confronted with the problem of low conversion of cyclohexene(less than 10%).Catalyst modification appears an economic and effective method to improve the conversion of cyclohexene.Hierarchical HZSM-5 was constructed by the post-treatment method of desilication.The effects of alkali type,alkali concentration,treatment temperature and treatment time on the physicochemical properties of HZSM-5 catalyst and the catalytic performance were investigated in detail.The experimental results show that the HZSM-5 catalyst obtained at the conditions of 0.4 mol/L NaOH treated at 323 K for 3 h has the best catalytic performance,and the conversion of cyclohexene can reach 12.98%.The characterization results indicate that the improvement of the catalytic performance of HZSM-5 zeolite is a comprehensive result of mass transfer intensification and the appropriate acidity on the catalyst surface.