Patent ID: 6458736
Filing Date: 2002-10-01
Classification: B01J,C07C,C10G,Y02P

Abstract:
A process for preselectivating a catalyst for use in the vapor phase disproportionation of toluene comprising:a. providing a zeolite-bound zeolite catalyst which comprises: (i) first crystals having an average particle size greater than about 0.1 micron of a first zeolite selected from the group consisting of MFI or MEL and having a silica to alumina mole ratio of from about 10:1 to about 200:1; and (ii) a binder comprising second crystals having an average particle size that is less than the average particle size of said first crystals of a second zeolite selected from the group consisting of MFI or MEL and lower acidity that said first zeolite, wherein the zeolite-bound zeolite catalyst contains less than 10% by weight, based on the weight of the first and second zeolite, of non-zeolitic binder; and b. contacting said zeolite bound zeolite catalyst with a toluene stream at a temperature in the range of between about 540Â° C. to about 650Â° C. at a pressure within the range of from about 1 to about 100 atmospheres and a weight hourly space velocity in the range of about 0.1 to about 20, wherein said toluene stream further contains hydrogen at a H2/toluene ratio of 0 to about 2, until at least about 2% by weight of coke is deposited on the surface of said catalyst.