DESILICATED ZSM-5 BASED CATALYSTS FOR XYLENE ISOMERISATION Russian patent published in 2020 - IPC B01J29/40 B01J29/42 B01J29/48 B01J35/10 C01B39/38 B01J37/00 C07C5/27 C07C15/08 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing a xylene isomerisation catalyst (versions), comprising steps of: (i) contacting a zeolite-based starting material of the ZSM-5 type, having molar ratio of silicon dioxide to aluminum oxide from 20 to 50 and mesopore surface area in range of 50 m²/g to 200 m²/g, in reactor with base at temperature from 20 °C to 100 °C during alkaline treatment period from 1 minute to 10 hours to obtain intermediate zeolitic material, wherein zeolite type ZSM-5 is in base in amount of 1 wt % to 20 wt %, in which base is added to reactor portionwise or continuously during alkaline treatment period; (ii) recovering intermediate material based on zeolite of type ZSM-5 of step (i); (iii) contacting the intermediate zeolite material with the acid at temperature of 20 °C to 100 °C during the acid treatment period from 1 minute to 10 hours to obtain an acid-treated product based on the ZSM-5 type zeolite; (iv) recovering an acid-treated product based on ZSM-5 type zeolite and (v) calcining the acid-treated zeolite-based material of the ZSM-5 type at a temperature in range of 300 °C to 700 °C for a period of time in range of 0.2 to 6 hours to obtain a product based on the desilicated ZSM-5 type zeolite with molar ratio of silicon dioxide to aluminum oxide from 20 to 150 and with surface area of mesopores in range from 100 m²/g to 400 m²/g.

EFFECT: technical result is improved characteristics of obtained catalyst.

6 cl, 14 dwg, 9 tbl