Zeolite based catalyst of modified mazzite structure type and its use for the dismutation and/or transalkylation of alkylaromatic hydrocarbons

摘要

The invention concerns a catalyst comprising at least one matrix and at least one zeolite of structure type mazzite, preferably omega zeolite, comprising silicon and aluminium, at least partially, preferably practically completely in its acid form, said zeolite having been prepared by dealuminization of the framework, by means of at least one treatment using at least one solution of a fluorosilicate of a cation in a proportion of 0.05 to 5 moles per mole of aluminium contained in the dry zeolite, said catalyst optionally comprising at least one element selected from groups IB and VIII of the periodic classification of the elements. The invention also concerns the use of said catalyst for the dismutation of alkylaromatic hydrocarbons, and preferably for the dismutation of toluene to produce benzene and xylenes, and/or for the transalkylation of alkylaromatic hydrocarbons, preferably for the transalkylation of toluene and trimethylbenzenes to produce xylenes.