METHOD OF DISPROPORTIONATING TOLUENE Russian patent published in 1999 - IPC

FIELD: chemical industry. SUBSTANCE: method comprises treatment of molecular sieve catalyst selected from group consisting of ZSM-6, ZSM-11, ZSM-22, ZSM-23 and ZSM-35, preferably ZSM-5 with organosilicon agent which is selective to para-xylene and contact of reaction stream containing toluene with said catalyst at temperature of 350-540 C, pressure of 100-35.000 KPa, volumetric pressure stock feed rate of 0.1-20 h^-1 and hydrogen to hydrocarbon molar ratio of 0.1-2.0. Paraxylene selective organosilicon agent is volatile organosilicon compound selected from siloxanes, silanes and disilanes, and catalyst is treated with said selective agent by feeding selective agent in amount of 0.1-50 wt % based on toluene weight and feeding reaction stream containing toluene for 300 hours to obtain product comprising at least 90% of para-xylene based on C₈ component during conversion of 15 wt % of toluene. EFFECT: regioselective process for preparing para-xylene from toluene and commercially acceptable levels of toluene conversion are maintained. 16 cl, 31 ex, 14 tbl