FIELD: chemistry.
SUBSTANCE: invention describes a method of obtaining middle distillates from a paraffin fraction obtained through Fishcer-Tropsch synthesis using a hydrocracking/hydroisomerisation catalyst which contains at least one hydrogenating-dehydrogenating element selected from a group comprising group VIB and group VIII periodic table elements, 0.01-6% phosphorus as a dopant and a non-zeolite substrate based on aluminium silicate, wherein said aluminium silicate has the following characteristics: 5-95 wt % silicon oxide content, less than 0.03 wt % sodium, total pore volume of 0.45-1.2 ml/g measured using mercury porosimetry,porosity is such that ii) volume of mesopores with diametre of 40-150 Ǻ and average pore diametre of 80-140 Ǻ is 30-80% of the total pore volume measured with mercury porosimetry, ii) volume of macropores with diametre of over 500 Ǻ is 20-70% of the total pore volume measured with mercury porosimetry, specific BET surface area is 100-550 m2/g, the X-ray pattern contains at least main characteristic spectra of at least one of transition aluminium oxide included in the group of alpha, rho, chi, eta, gamma, kappa, theta and delta aluminium oxides.
EFFECT: improved method.
20 cl, 2 tbl, 4 dwg, 3 ex
