According to this invention, a Ni—Mo—W trimetallic catalyst supported on porous
alumina is obtained that shows very
high activity for hydrotreating (HDT) of gasoils, particularly deep
hydrodesulfurization (HDS) and hydrodesnitrogenation (HDN) of straight run gasoil in conditions of moderate pressure.When the catalyst is applied to HDT of diesel, the NiMoW catalyst exhibits high catalytic activity. The content of
sulfur and
nitrogen in the resulting diesel can be reduced from 13,200 to 10 ppm and
nitrogen from 360 ppm to less than 1 ppm, under moderate pressure, temperature and space-velocity (LHSV) similar to those of an industrial unit.The catalytic composition, of trimetallic type, is prepared from an
alumina support of
high surface area to which a solution containing a
metal precursor of an element of group VIB is added, followed by other solution that contains one of the precursors of the active metallic phase, a solution containing another of the precursors of the active metallic phase from group VIB, a
metal promoter of group VIII and an additive
promoter of acidity from group VB, and finally another solution containing a
metal of group VIB, a metal of Group VIII and an
organic compound, the used
route promotes the preferential formation of well dispersed structures of the used metals on the support of porous
alumina, less
refractory to
sulfidation, with high stacking and short lengths of metal sulfides formed in the resulting
hydrodesulfurization catalyst. In the formulation, at least a percentage, but not all the Mo is replaced by W, in a Mo / W
molar ratio of 0.6 to 2.0.