Effects of pore structure and acidity over Beta and Y zeolites with a range of Brønsted and Lewis acid sites on their catalytic behaviour in the transalkylation reaction were investigated. The tests were conducted for a time-on-stream (TOS) of 50 h in a fixed-bed reactor at 400 °C, 10 bar, H₂/HC = 4, and WHSV=5 h⁻¹ with a 50:50 wt. % toluene:124-TMB mixture as feedstock. While initial (TOS ≤3 h) TMBs conversion was similar, wide differences were evident as the effects of partial deactivation became apparent with TOS. Zeolite Beta (Si/Al = 12.5) exhibited highest conversion and xylenes yield. As the Si/Al ratio of zeolite Beta is increased, the performance dropped whereas an opposite trend was observed for Y zeolites underscoring the importance of optimum level of dealumination depending on the zeolite structure. Isomerization of 124-TMB was observed over Beta which was not sustained by Y. The existence of separate active sites for TMB isomerization and its transalkylation with toluene in Beta is suggested.

研究了在一定范围内具有布朗斯台德和路易斯酸位的β和Y沸石上孔结构和酸度对其烷基转移反应催化性能的影响。在固定床反应器中于400°C，10 bar，H ₂ / HC = 4和WHSV = 5 h ^-1的条件下进行了50小时的运行时间（TOS）测试50:50 wt。用％甲苯：124-TMB混合物作为原料。尽管最初的（TOS≤3 h）TMBs转化是相似的，但由于TOS导致部分失活的影响变得明显，因此差异很大。β沸石（Si / Al = 12.5）具有最高的转化率和二甲苯收率。随着β沸石的Si / Al比的增加，性能下降，而对于Y沸石观察到相反的趋势，这强调了取决于沸石结构的最佳脱铝水平的重要性。在β上观察到124-TMB的异构化，而Y并不能维持它。建议存在单独的TMB异构化活性位点，以及它在甲苯中与甲苯的烷基转移作用。