Patent ID: 6617275
Filing Date: 2003-09-09
Classification: B01J

Abstract:
A process for preparing a catalyst for the dehydrocyclodimerization of C2-C6 aliphatic hydrocarbons, the process comprising:a) forming a bound zeolite comprising a zeolite having a silica to alumina molar ratio greater than about 20 and a pore diameter from about 5 Ã¥ to about 6 Ã¥, and an essentially non-acidic binder; b) calcining the bound zeolite at a temperature from about 450Â° C. to about 700Â° C. for a period from about 1 to about 20 hours to yield a calcined composite; c) contacting the calcined composite with an aqueous solution of a gallium metal salt selected from the group consisting of gallium nitrate, gallium chloride, gallium bromide, gallium hydroxide, and gallium acetate to yield a gallium-impregnated composite; d) reducing the gallium-impregnated composite at a temperature from about 400Â° C. to about 700Â° C. for a period from about 1 to about 10 hours in a hydrogen-containing gas to yield a reduced gallium impregnated composite; e) oxidizing the reduced gallium impregnated composite at a temperature from about 400Â° C. to about 700Â° C. for a period from about 1 to about 10 hours in an oxidizing atmosphere comprising air and steam where the steam is present in an amount from about 1% to 100% of saturation to yield the catalyst.