Patent ID: 6217746
Filing Date: 2001-04-17
Classification: C10G

Abstract:
A two stage hydrocracking process, which process comprises:(a) passing hydrogen and a feed stream comprising hydrocarbons having boiling points above 700.degree. F. into a first hydrocracking zone operated at hydrocracking conditions including a first pressure and containing a hydrocracking catalyst and producing a first hydrocracking zone effluent stream comprising hydrogen, hydrogen sulfide, unconverted feed components and product hydrocarbons;(b) separating the first hydrocracking zone effluent to yield a recycle gas stream and a first liquid process stream, which liquid process stream is passed into a product fractionation zone producing a distillate product stream and a bottoms stream comprising unconverted feed components;(c) passing the bottoms stream and a makeup hydrogen gas stream into a second hydrocracking zone operated at paraffin selective hydrocracking conditions which include a lower second pressure, and producing a second hydrocracking zone effluent stream;(d) separating the second hydrocracking effluent stream into a vapor phase stream and a liquid phase stream, and passing the liquid phase stream into the product fractionation zone; and(e) compressing the vapor phase stream and passing the vapor phase stream into the first hydrocracking reaction zone as a makeup gas stream.