SELECTIVE PARA-XYLENE PRODUCTION BY TOLUENE METHYLATION

摘要

There is provided a process for the selective production of para-xylene which comprises reacting toluene with methanol in the presence of a catalyst comprising a porous crystalline material having a Diffusion Parameter for 2,2 dimethylbutane of about 0.1-15 sec<-1> when measured at a temperature of 120 DEG C and a 2,2 dimethylbutane pressure of 60 torr (8kPa). The porous crystalline material is preferably a medium-pore zeolite, particularly ZSM-5, which has been severely steamed at a temperature of at least 950 DEG C. The porous crystalline material is preferably combined with at least one oxide modifier, preferably including phosphorus, to control reduction of the micropore volume of the material during the steaming step.