Low-sulphur heating oil - by desulphurising distillate residues in two stages, using carrier of varying pore size in hydrofining stage

摘要

Low-S heating oil, gasoline and middle distillates are produced from petroleum distillate residues contg. metals and asphalts, by (a) treating the residue at 450-500 degrees C and 150-250 atmos., in presence of H2(-contg. gas) and of a suspended hydrogenation catalyst and/or a high-surface solid, (b) sepng. the prod. in a press. separator into a residue contg. the asphalts,metal cpds., catalyst or solids, and a fraction free from these substances, (c) passing this fraction, as a whole, or the portion boiling at 340 degrees C after partial condensn. and/or distn. to a hydrofining stage in which the S cpds. are removed at 50-350 (150-250) atmos., a loading of 1-10 (2-6) vol/vol/hr. and at 300-450 degrees C(250-420 degrees C) in presence of a hydrogenation gas, over a solid catalyst in which the carrier is a combination of a narrow-pore and a wide-pore Al2O3, stabilised with a weakly acid aluminosilicate; the pore sizes are such that pores of 20-100 A form, based on total pore vol., 40-70%, those of 500-5000 A 20-60%, and those of 100-500A 15%. Coke and heavy metals are not deposited in the narrow pores, and transport of the hydrocarbon molecule is not hindered in the wide pores.