Patent ID: 6451198
Filing Date: 2002-09-17
Classification: C10G

Abstract:
A process for transforming a gas oil cut into a diesel fuel having a cetane number of at least 49, less than 100 ppm of sulphur, less than 200 ppm of nitrogen and less than 10% by volume of aromatic compounds, comprising:a) passing the gas oil cut and hydrogen under denitrogenation and desulphurisation conditions in at least one step over a catalyst comprising a mineral support, at least one metal or metal compound from group VIB of the periodic table in a quantity, expressed as the weight of metal with respect to the weight of finished catalyst, of about 0.5% to 40%, at least one metal or metal compound from group VIII of the periodic table in a quantity, expressed as the weight of metal with respect to the weight of finished catalyst, of about 0.1% to 30%, and phosphorous and boron or at least one boron compound in a quantity, expressed as the weight of boron trioxide with respect to the weight of the support, of about 10% or less, to produce an at least partially denitrogenated and desulfurised effluent; (b) steam stripping the effluent from (a) and, optionally, recycling hydrogen therein for use in (a); (c) passing at least a portion of the steam stripped effluent from (b) with hydrogen under dearomatisation conditions over a catalyst comprising, on a mineral support, at least one noble metal or noble metal compound from group VIII in a quantity, expressed as the weight of metal with respect to the weight of finished catalyst, of about 0.01% to 20% to produce a denitrogenated, desulfurised and dearomatised diesel fuel, and, optionally, recycling hydrogenation for use in (c); with the further provision that fresh hydrogen is introduced into (a) and (c) independently of each other, and optionally that recycle hydrogen from (b) is recycled to only (a) and optionally recycle hydrogen from (c) is recycled to only (c).