Process for preparing a catalyst for aromatic production
AssigneeUop LLC
InventorsSanjay B. Sharma, John Kulach, Aaron James Imrie
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Abstract
A novel process for converting C2 to C6 aliphatic hydrocarbons to aromatics and catalyst for use in this process are disclosed. The catalyst that contains a zeolite having a silica to alumina molar ratio greater than about 20 and a pore diameter from about 5 Å to about 6 Å, an essentially non-acidic binder, and a gallium component. The binder is selected from silica, zirconia, titania, and mixtures thereof and results in a catalyst formulation having both enhanced selectivity to desired C6-C9 aromatic products and improved stability compared to prior art compositions. Preferred zeolites that can be used include those of the MFI structure type, with ZSM-5 being a specific example.
Claims14
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 Å to about 6 Å, and an essentially non-acidic binder;
- b) calcining the bound zeolite at a temperature from about 450° C. to about 700° 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 400° C. to about 700° 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 400° C. to about 700° 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.
Dependencies are inferred from the claim text.