PROCESS FOR THE HYDROGENATIVE CRACKING OF HYDROCARBON OILS

摘要

1356161 Hydrocracking SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 6 July 1971 [8 July 1970] 31632/71 Heading C5E A hydrocarbon oil is hydrocracked and fractionated, and a higher-boiling fraction subjected to a second hydrocracking together with added kerosine. The product of this second hydrocracking is returned to the fractionator. As shown, a heavy gas oil is supplied at 1, receives hydrogen from a line 2 and is heated in a heatexchanger 4 and a furnace 7. It is passed through beds of catalyst in a cracker 9, temperature being controlled by the addition of cold gas at 101, 1011 and 10111. The effluent is cooled in the heat exchanger 4, mixed with effluent from the second cracking stage via line 12 and cooled at 14. Gas and liquid phases are separated at 16, ammonia and H 2 S are washed out of the gas at 18, and the gas recycled through the line 10 with make-up at 22. The liquid from the separator is fractionated in three columns 24, 27 and 31, from which are taken off hydrocarbons up to butane at 25, a light gasoline (up to 80‹ C.) at 28, a naphtha (80-150‹ C.), suitable for reforming, at 29, and oil boiling at 150-270‹ C, suitable for aviation fuel, at 11. The bottoms from the last column 31 are taken off by line 32, a straight-run kersonine is added by line 3 and hydrogen by line 33. The mixture is heated in heat-exchanger 35 and furnace 38 and cracked in cracker 40 with gas quenches 331 and 3311. The effluent from the second cracking is cooled in heat-exchanger 35 and taken by line 12 to be mixed with that from the first cracking. The first-stage catalyst is preferably sulphur-resistant, and may have a support of silica, alumina, magnesia, zirconia, titania, P 2 O 5 9r boria, with a hydrogenating component of Cu, Ag, W, Mo, Co, Ni, Pt or Pd, as metal, oxide or sulphide, and activated with fluorine. The second-stage catalyst may be sulphur-sensitive, and may have a support that contains silica and one or more of Al 2 O 3 , MgO, ZrO 2 , TiO 2 and B 2 O 3 , e.g. a zeolitic molecular sieve, and may have the same hydrogenating components and activator.