Patent ID: 8709234
Filing Date: 2014-04-29
Classification: C10G

Abstract:
1. A process for producing middle distillates from a paraffinic feed produced by Fischer-Tropsch synthesis unit, comprising the following steps in succession: a) separating at least one gaseous C4− fraction, termed the light fraction, with an end boiling point of less than 20° C., from an effluent derived from the Fischer-Tropsch synthesis unit to obtain a single C5+ liquid fraction, termed the heavy fraction, with an initial boiling point in the range of 20° C. to 40° C.; b) hydrogenating the unsaturated olefinic type compounds of at least a portion of said heavy liquid fraction C5+, in the presence of hydrogen and a hydrogenation catalyst at a temperature in the range of 100° C. to 180° C., at a total pressure in the range of 0.5 to 6 MPa, at an hourly space velocity in the range of 1 to 10 h c) hydroisomerizing/hydrocracking the entire liquid hydrogenated effluent from step b) with no prior separation step in the presence of hydrogen and a hydroisomerization/hydrocracking catalyst; d) distilling resultant hydrocracked/hydroisomerized effluent from step (c) and wherein said hydroisomerization/hydrocracking catalyst comprises up to 3% by weight of at least one hydro-dehydrogenating element selected from noble metals from group VIII and a support comprising at least one silica-alumina, said silica-alumina having the following characteristics: