Patent ID: 7404890

Claim:
A process for producing middle distillates from a paraffin feed produced by the Fischer-Tropsch process, comprising the following successive steps: a) separating at least one light fraction from the feed to obtain a single fraction, termed the heavy fraction, with an initial boiling point in the range 120-200° C.; b) optionally, hydrotreating said heavy fraction, optionally followed by a step c) removing at least a portion of any water produced, d) passing at least a portion of said optionally hydrotreated heavy fraction over an amorphous hydroisomerisation and/or hydrocracking catalyst, which catalyst is not fluorinated, conversion over said catalyst of products with boiling points of 370° C. or more into products with boiling points of less than 370° C. being more than 80% by weight; e) distilling the hydrocracked and/or hydroisomerised fractions to obtain middle distillates, comprising at least one of a kerosene cut and a gas oil cut and recycling a residual fraction with a boiling point above that of said middle distillates to step d); f) steamcracking said at least one light fraction from (a).