IMPROVED CATALYST FOR CONVERTING ETHYLBENZENE IN A METHOD FOR ISOMERISATION OF XYLENE Russian patent published in 2020 - IPC C07C5/27 C07C15/08 B01J29/40 

FIELD: chemical or physical processes.

SUBSTANCE: invention relates to a method for isomerisation of a stream of precursors containing xylenes and ethylbenzene. Method comprises: contacting a stream of starting materials with a first catalyst in a two-layer catalyst system to produce a first effluent; and contacting the first effluent with the second catalyst in the two-layer catalyst system to produce a second effluent, wherein the first catalyst comprises an aluminosilicate molecular sieve, having a permeability index in range of 1 to 12 and containing 0.5 to 0.8 wt % aluminum, where the aluminosilicate molecular sieve is an aluminosilicate zeolite of the ZSM-5 type; where first catalyst contains hydrogenating metal; where first catalyst is active in conversion of ethylbenzene and second catalyst exhibits activity in isomerisation of xylenes, where 20 % or more of ethylbenzene in the stream of starting substances is converted to hydrocarbons which are not ethylbenzene, and where the ratio of the degree of conversion of ethylbenzene and loss of xylene is at least 45, when 30 % ethylbenzene is converted.

EFFECT: disclosed catalyst enables to convert ethylbenzene to benzene with high selectivity without loss of xylene.

11 cl, 3 tbl, 1 ex