The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 1990
Filed:
Dec. 12, 1988
Susan P Donnelly, Yardley, PA (US);
Mobil Oil Corporation, New York, NY (US);
Abstract
Shape selective zeolites, such as ZSM-5, are added to the equilibrium catalyst in a catalytic cracking unit in large amounts. Sufficient fresh zeolite is added to result in an unacceptable increase in production of wet gas (C.sub.3 /C.sub.4) by the catalytic cracking unit, if operated at normal charge rates and operating conditions. To compensate, conditions in the catalytic cracking unit are adjusted, such as by reducing feed rate, catalyst/oil ratio, or cracking reaction temperature, to reduce the production of 'light ends' to an amount which can be tolerated by the catalytic cracking unit. Within a few days to a few weeks, excessive production of wet gas will diminish so that unit operation may be returned to normal. Resumption of normal cracking operations using a catalyst inventory containing a relatively large amount of shape selective zeolite additive results in significant increases in the octane number of the catalytically cracked gasoline.