De-asphalting of hydrocarbon residues - by solvent extraction at elevated temps and pressures

摘要

Heavy petroleum distillate residues of high sulphur content are treated to remove asphaltenes, metal-contg. and ash-forming cpds. by liquid-liquid extraction of a temp. above the softening temp. of the asphaltene concentrate and a pressure above the vapour pressure of the solvent at that temp. - Suitable solvents are paraffins with 4-8C atoms, and the extraction temp. is pref. 140 - 190 degrees C, using a ratio of solvent to distillate pref. between 2:1 and 4:1 by wt. - The de-asphalted extract is subsequently subjected to catalytic cracking using metal oxides of Groups VI and VIII on an alumina carrier at 350 - 450 degrees C under 100 - 300 atmos. pressure with a volume ratio of hydrogen to de-asphalted oil between 200 : 1 and 2000 : 1. The products can be used as water fuels and boiler fuels.