On the influence of alumina as a binder on the performance of Pt-Beta catalyst during the transalkylation of toluene and 1,2,4-Trimethylbenzene

The influence of the addition of 20–50 wt% alumina binder on the physical, chemical and catalytic properties and performance of zeolite Beta loaded with 0.08 wt% Pt for the transalkylation of 1,2,4-trimethylbenzene (124-TMB) with toluene was studied. The catalytic tests were conducted in a fixed-bed reactor at WHSV of 5 h⁻¹, 400 °C and 10 bar with a mixture of toluene and124-TMB feed in 50:50 wt % ratio. The catalyst and binder mixture reduced the overall activity with increasing amount of binder. The progressive addition of the binder had a more negative effect on toluene conversion than 124-TMB which is explained by the increase in isomerization and disproportionation side reactions. The results suggested that Pt-Beta is responsible for the dealkylation reactions as the light products were decreased with increased binder contents. The xylenes yield was reduced upon addition of the binder from 39.5 to 30.5 wt %. This can be explained by the increase of amount of coke formation per unit area of Pt-Beta over the catalysts and by the re-distribution of platinum particles.