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AssigneeUop LLC
InventorsJoseph A. Kocal, Christopher D. Gosling, Paul J. Kuchar, Tamotsu Imai
Estimating the term…
This invention relates to a process for reactivating a dehydrocyclodimerization catalyst. Dehydrocyclodimerization catalysts which contain an aluminum phosphate binder can be deactivated when they are exposed to hydrogen at temperatures above 500.degree. C. The instant process restores substantially all of the catalyst's lost activity. The process involves treating the catalyst with an aqueous solution of a weakly acidic ammonium salt or a dilute acid solution at a temperature of about 50.degree. to about 100.degree. C. for a time of about 1 to about 48 hours. An ammonium nitrate solution is preferred. Next the catalyst is calcined at a temperature of about 500.degree. to about 700.degree. C. for a time of about 1 to about 15 hours to provide a reactivated catalyst. The catalyst can be reactivated several times using this process.
A process for reactivating a dehydrocyclodimerization catalyst comprising a zeolite having a Si:Al ratio greater than about 10 and a pore diameter of about 5-6 .ANG., an aluminum phosphate binder and gallium, said catalyst having been deactivated by exposure to hydrogen at a temperature above 500.degree. C., the process comprising treating the catalyst with an aqueous solution of a weakly acidic ammonium salt or a dilute acid solution at a temperature of about 50.degree. to about 100.degree. C. for a time of about 1 to about 48 hours and then calcining the treated catalyst at a temperature of about 500.degree. to about 700.degree. C. for a time of about 1 to about 15 hours, thereby providing a reactivated catalyst.
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