Patent GB-536813-A (GB)
Title: An improved manufacture of hydrocarbons boiling within the gasoline range
IPC: C07C9/16
Filed: 1939-10-23
Abstract: 536,813. Gasoline. STANDARD OIL DEVELOPMENT. CO. Oct. 23, 1939, No. 28512. Convention date, Dec. 7, 1938. [Class 2 (iii)] A mixture containing low boiling olefines and isoparaffins is subjected to catalytic polymerization and alkylation in separate steps, and the spent catalyst from the alkylation is utilized in the polymerization step. In a modification, conditions are employed which cause polymerization of isobutylene only. The resulting diisobutylene is separated and hydrogenated and the remainder of the product is subjected to alkylation. The C 8 -C 10  fraction of the alkylation products is combined with the hydrogenated diisobutylene while the remainder is returned to the alkylation reaction zone with fresh feed. , In Fig. 1, refinery C  4  cut is fed into a polymerization chamber 1 containing a liquid activating medium, e.g. sulphuric acid of 60-75 per cent. at 150‹-225‹F. wherein copolymerization of normal and isobutylenes takes place. The resulting mixture of acid, polymers and unreacted material passes to settler 6, the settled acid being returned by pipe 11 to the chamber 1. Reaction products containing acid which has been longest in contact with hydrocarbons pass to a second settler 13. Spent acid leaves by pipe 14 and the hydrocarbcns, after passing pressure release valve 17 enter flash chamber 16. Unreacted hydrocarbons, chiefly normal paraffins leave the flash chamber at 18 and the ploymers are passed after cooling to a second acid chamber 22 containing acid of above 90 per cent. Isoparaffins are introduced through pipe 27 and the reaction products pass to settlers 29 and 37. Spent acid from settler 37 passes to the polymerization chamber. The hydrocarbons from settler 37, after passing a pressure release valve 40 enter a flash chamber 41 so controlled that C 4   hydrocarbons are vaporized. The liquid products composed of C 5  and higher hydrocarbons are passed to a fractionating column 43 so operated that C 8  hydrocarbons are withdrawn through line 44. C 9  and higher products pass through line 45,to the acid chamber 22. The lighter fractions, after cooling and compression are combined with the C  9  and higher fraction and also returned to the acid chamber 22. When the isobutylene is separately polymerized the apparatus shown in Fig. 2 is employed. Acid in,chamber 1 has a concentration of 60-75 per cent. and the hydrocarbons from settler 13 are passed to a fractionating tower 52 which is controlled so that a C 8  cut is drawn off through line 53. The latter cut passes to a hydrogenating chamber 54 containing a catalyst such as the oxides or sulphides of metals of group 6. The products pass first into separator 56, the hydrogen being returned to the chamber 54 through pipe 57 and then into separator 59. Lower hydrocarbons from the latter are cooled and passed to a separator 63 whence liquid hydrocarbons are fed through pipe 66 to the alkylation chamber 22. Hydrogenation products leaving the bottom of separator 59 meet alkylation products from the settler 37 and are fractionated in a fractionator 69. A third system is described having four chambers in which solid catalysts are employed. In each chamber in turn alkylation, polymerization and regeneration of the catalyst take place.