HYDROCRACKING PROCESS FOR HIGH END POINT FEEDS

1297803 Hydrocracking; hydrorefining ESSO RESEARCH & ENG CO 25 Nov 1969 57601/69 Heading C5E An hydrocarbon feed comprising or consisting of a fraction boiling in the range 350-430‹ F. is hydrocrackfined, in the presence of hydrogen, using a catalyst comprising a hydrogenating component and a zeolite cracking component having the crystal structure of faujasite or mordenite, at 400-850‹ F. and 200-2000 p.s.i.g. so that not more than 10 wt. per cent of the feed is converted to C 4 and lower boiling products to produce a naphtha having a lower boiling range, and a higher octane value than the feed. Suitable hydrogenating components are (a) Zn, Ni or Co together with Mo, W or Sn and (b) Pt, Pd, Ir, Rh, Ru or Os and suitable zeolite cracking components are hydrogen Y faujasites having SiO 2 : Al 2 O 3 ratio greater than 3 and modified with Zn, Co, Ni, Pt or Pd. The catalysts are made by ion-exchange and can be sulphided before use. Suitable feeds are straight run C 5 -750‹ F. distillates and/or cracked fractions. A stream 2 of coker distillate gas oil, cycle oil from catalytic or thermal cracking or aromatic straight run gas oil is hydrofined at 6 using a catalyst containing Co and Mo or Ni and W on alumina or alumina containing coprecipitated silica and then hydrocracked at 10, using a catalyst comprising silicaalumina, silica-magnesia, silica-zirconia, aluminium phosphate or an X or Y zeolite together with 0À05-25% of Cr, W, Co, Ni, Pt, Pd, Rh or Ir, to provide 20-60% conversion to gasoline. The effluent stream 11 is scrubbed with water at 12 and then fractionated at 22 to provide a stream 24 of C 5 -350‹ F. naphtha, a stream 25 of 350-430‹ F. naphtha and a stream 45 of 430‹ F. bottoms which is recycled at least in part to a hydrocracker 17. The stream 25 is reacted in the hydrocrackfiner 30 in admixture with a heavy naphtha 26 and at least part of the effluent stream 30 is fractionated at 47 to provide a stream 49 boiling from 320-550‹ F. and a bottoms fraction 50.