Estimated Contribution of Modifying Elements to the Activity of Zeolite Catalysts in Alkylation of Toluene with Methanol

Resumo

Results are presented of studies aimed to develop effective catalytic systems synthesized from various types of zeolites for the reaction of toluene alkylation with methanol to obtain xylenes with increased content of para-xylene. The influence exerted by the active components (Mg, Cu, Mo, Zn, etc.) and promoters (fluorine compounds CsF, KF, AlF₃ and phosphorus) on the activity in the process under study of catalysts produced on the basis of high-silica zeolites TsVM and TsVK was examined. It was shown that the highest efficiency is exhibited by the catalytic systems synthesized on the basis of the hydrogen form of TsVK zeolite, modified with cations of the active metal magnesium and a promoter CsF. Prolonged tests of the catalyst synthesized in this way demonstrated acceptable for practical implementation stable activity and selectivity for xylenes with increased content of para-xylene.