GB534856A - An improved catalytic cracking process - Google Patents

Abstract

534,856. Cracking oils. STANDARD OIL DEVELOPMENT CO. Sept. 15, 1939, No. 25905. Convention date, Dec. 29, 1938. [Class 32] Heavy oils are converted into gasoline by forcing the oil through a narrow constricted heated passage way, e.g. a tubular coil under super atmospheric pressure and at such temperature that the oil is completely vaporized, adding to the vapours a silicious catalyst in the proportion of ¢-10 lbs. per barrel of crude feed, and maintaining the vapours and catalyst in contact at pressures above 200lbs. per sq. inch and at temperatures above 900‹F. until substantial conversion of the oil into gasoline is obtained. The catalyst may be added to the vapours in the dry state or mixed with an easily vaporizable liquid, e.g. water or light oil, to form a slurry. The crude feed is pumped through a coil 3 heated to 800-900‹F. under a pressure of 200 lbs. per sq. inch and the vapours formed are passed into a coil 9 where they are mixed at successive points 8a, 8b, 8c, with a catalyst slurry supplied from a vessel 6. The catalyst and vapour mixture is preferably passed through a reaction drum 12 but may pass directly through line 13 to a fractionating tower 14 from which gasoline fractions are withdrawn through condenser 18 to separator 19. A middle fraction may be collected through line 20 and re-cycled to mix with the feed oil or to form a slurry with the catalyst. Heavy residues are withdrawn through line 24 and cooler 25 to a filter or other catalyst separating device 26 and may be re-cycled in part through line 28. The catalyst may comprise acid treated clays, synthetic gels, or co-precipitated gels of silica and alumina. Specification 411,477 is referred to.