Gasoline upgrading process

U.S. Patent Number: 5348641

Abstract: Low sulfur gasoline of relatively high octane number is produced from a catalytically cracked, sulfur-containing naphtha by hydrodesulfurization followed by treatment over an acidic catalyst, preferably an intermediate pore size zeolite such as ZSM-5. The treatment over the acidic catalyst in the second step, which is carried out in a hydrogen atmosphere which is essentially free of hydrogen sulfide and ammonia, restores the octane loss which takes place as a result of the hydrogenative treatment and results in a low sulfur gasoline product with an octane number comparable to that of the feed naphtha. The hydrogen supplied to the second step may be make-up hydrogen with recycle hydrogen routed to the hydrodesulfurization step after removal of ammonia and hydrogen sulfide in a scrubber.

Inventors: Shih; Stuart S. (Cherry Hill, NJ)

Assignee: Mobil Oil Corporation (Fairfax, VA)

Application Number: 07/880,373

Issued: 1994-09-20

Expired: 2006-09-20

Classes: 208/89 ; 208/212; 208/213

Field of search: 208/58,89

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