CATALYTIC ACTIVITY OF A ZEOLITE DISC SYNTHESIZED THROUGH SOLID-STATE REACTIONS

ZSM-5 zeolite in a disc-shaped form was synthesized by a new method in which reactions occurred in the solid state. The proton form of the z eolite was prepared by ion exchange of the sodium ions of the disc-sha ped pellet in hydrochloric acid solution. The catalyst prepared was ch aracterized by SEM, thermogravimetry, nitrogen adsorption and ammonia TPD. High p-xylene selectivity was observed for the new disc-shaped ZS M-5 zeolite catalyst in the alkylation of toluene with methanol. This catalytic feature was attributed to the inherent character of the zeol ite, since its structure consisted of inter-grown individual HZSM-5 cr ystals forming secondary mesopores which promote the high gas permeabi lity of the zeolite disc. (C) 1998 Elsevier Science B.V. All rights re served.