1780.  JOHNSON, P. H. (Phillips Petroleum Co.). Treatment of Synthetic Gasoline. United States Patent 2,501,223, Mar. 21, 1950; appl. filed Nov. 10, 1947. Serial No. 785,146; 7 claims (Cl. 196-50).

Raw synthetic gasoline of the Fischer-Tropsch type is preheated and passed over a cracking catalyst, such as bauxite, in a 1^st contact zone at 700º-950º F. and 0-200 p. s. i. Undesirable oxygenated compounds are removed, and the odor is improved. Effluent from the 1^st zone is passed through a 2d zone containing the same or a different catalyst along with superheated steam, temperature 600º-950º F. pressure 0-200 p. s. i. 20-65 lb. of steam per bbl. gasoline is used in the 2d step. The space velocity in both zones is 0.5-10 liquid vol. charge per vol. catalyst per hr. The size of the 2 zones may be the same or may be varied, depending on the nature of the gasoline treated. Effluent from the 2d zone is fractionated, and the desired product such as a stabilized 700º F. end-point gasoline is separated and recovered. Catalyst can be regenerated with steam and air. Silica alumina and activated montmorillonite are also mentioned as catalysts. Example: 2 runs were made using raw Fischer-Tropsch gasoline b. 110º-385º F., and ASTM unleaded octane No. 62 and a Br No. 67. In each run the charge was passed through a calcined bauxite catalyst at 745º F., 50 p. s. i., and a space velocity 1.4 liquid vol. per vol. catalyst per hr. In the 2d run 63 lb. steam per bbl. gasoline was added. A 3d run was made in which the product of the 1^st run was treated in the manner described for the 2d run, except the temperature was 700º F. The following data were obtained: