球磨晶种诱导制备丝光沸石及其烷基转移反应性能

Preparation of mordenite with ball-milled seeds and their performance in transalkylation reaction

针对甲苯与1,2,4-三甲苯烷基转移反应催化剂易失活的问题,以球磨丝光沸石(MOR)分子筛为晶种,诱导合成小粒径MOR分子筛,并经离子交换制得H-MOR催化剂。研究了反应温度、进料空速(WHSV)、原料分压等操作条件对催化剂性能的影响。结果表明,原位水热合成MOR分子筛粒径为20μm,而球磨晶种诱导24 h颗粒尺寸仅为3μm。氢离子交换16 h所制备H-MOR催化剂性能最优,反应温度为350℃、WHSV为3 h-1、二个原料分压均为1 kPa时,总转化率达56.9%,对二甲苯(PX)产率达8.9%,且催化性能稳定。

Catalyst deactivation is a challenging issue in the transalkylation of 1,2,4-trimethylbenzene(1,2,4-TMB)with toluene.Mordenite(MOR)zeolite with small particle size was prepared using ball-milled MOR zeolite as the seeds,and H-MOR catalysts were obtained by ion-exchange.The catalytic performance was evaluated under different reaction conditions including reaction temperature,weight hourly space velocity(WHSV)and reactant partial pressure.The particle size of MOR zeolite was 20μm through in-situ hydrothermal reaction,while the particle size was only 3μm by 24 h ball-milled seeds induction.The optimal catalytic performance was achieved at 350℃,WHSV of 3 h-1 and reactant partial pressure of 1 kPa on MOR zeolite after ion-exchange of 16 h,and the total conversion of 56.9%with para-xylene(PX)yield of 8.9%can be stably achieved.