Patent GB-601986-A (GB)
Title: Process for the production of aviation gasoline
IPC: C10G55/02
Filed: 1945-05-14
Abstract: A straight run naphtha boiling between 90 and 230 DEG  C. is cracked in pseudo liquid phase, i.e. above the critical temperature and pressure, a fraction boiling between 90 and 230 DEG  C. is separated, re-cracked in pseudo liquid phase, a light aviation blending stock and a heavy fraction boiling between 140 and 230 DEG  C. are separated, the heavy fraction is further cracked in pseudo liquid phase, and an aviation base stock boiling between 100 and 200 DEG  C. is separated.  The naphtha, preferably of aromatic or naphthenic nature and of B.R. 100-200 DEG  C., may be cracked at 540-580 DEG  C. and 40-100 kg/sq. cm. and the products fractionated to separate a second naphtha fraction, preferably of B.R. 100-200 DEG  C., and light hydrocarbons of C3-C5 which may be used in the subsequent cracking steps or worked up by alkylation, polymerization or cracking.  This second naphtha fraction is re-cracked under the same conditions, preferably with the addition of 5-15 or even 30 per cent by volume of the total feed of light hydrocarbons, for example those above specified. Methods of determining the optimum cracking conditions by measuring the B.R. of the product or its aromatic content are described.  The cracked product is fractionated to separate a naphtha, preferably of B.R. 100-200 DEG  C., which may be refined by sulphuric acid, adsorption agents, phosphoric acid, hydrogenation or otherwise to remove olefins and sulphur and, if desired, toluene, before further separating into a light aviation stock of B.R. 90 to 140-155 DEG  C., and a heavy fraction preferably of B.R. 150-200 DEG  C.  The latter is cracked under the same conditions preferably with addition of light hydrocarbons, and a fraction of B.R. 100-200, preferably 120-180 DEG  C., separated. This may be refined and blended with gasolines, hydrocarbons, di-isopropyl ether, tetra-ethyl lead, aromatic amines, and other blending agents.ALSO:A straight run naphtha boiling between 90 DEG and 230 DEG  C. is cracked in pseudo liquid phase, i.e. above the critical temperature and pressure, a fraction boiling between 90 DEG and 230 DEG  C. is separated, re-cracked in pseudo liquid phase, a light aviation blending stock and a heavy fraction boiling between 140 DEG  and 230 DEG  C. are separated, the heavy fraction is further cracked in pseudo liquid phase, and an aviation base stock boiling between 100 DEG  and 200 DEG  C. is separated.  The naphtha, preferably of aromatic or naphthenic nature and of B.R. 100-200 DEG C., may be cracked at 540-580 DEG  C. and 40-100 kg./sq. cm. and the products fractionated to separate a second naphtha fraction, preferably of B.R. 100-200 DEG  C., and light hydrocarbons of C2-C5 which may be used in the subsequent cracking steps or worked up by alkylation, polymerization or cracking.  This second naphtha fraction is re-cracked under the same conditions, preferably with the addition of 5-15 or even 30 per cent by volume of the total feed of light-hydrocarbons, for example those above specified. Methods of determining the optimum cracking conditions by measuring the B.R. of the product or its aromatic content are described.  The cracked product is fractionated to separate a naphtha, preferably of B.R. 100-200 DEG  C., which may be refined by sulphuric acid, adsorption agents, phosphoric acid, hydrogenation or otherwise to remove olefins and sulphur and, if desired, toluene removed, before further separating into a light aviation stock of B.R. 90 DEG  to 140-155 DEG C., and a heavy fraction preferably of B.R. 150-200 DEG  C.  The latter is cracked under the same conditions, preferably with addition of light hydrocarbons, and a fraction of B.R. 100-200 DEG , preferably 120-180 DEG  C., separated. This may be refined and blended with gasolines, hydrocarbons, diisopropyl ether, tetra-ethyl lead, aromatic amine and other blending agents.