Process of converting non-distillable residues of mixed-base or paraffin-base crude hydrocarbon oils

Claim 1

A process for converting a non-distillable residue of a mixed-base or paraffin-base crude hydrocarbon oil to a distillable precursor for petrochemical products including motor fuels which comprises donor solvent hydrovisbreaking said residue in a hydrovisbreaking zone in the presence of a circulated hydrogen donor solvent at a temperature in the range 380° to 480° C. and at a pressure in the range of 40 to 200 bars and producing a liquid product, separating said liquid product by a first distillation into a naphtha fraction boiling below 200° C., a medium fraction boiling at 200° to 500° C. and a residue fraction boiling above 500° C., subjecting a branch stream of said medium fraction to a catalytic treatment in the presence of molecular hydrogen, said treatment comprising a selective catalytic hydrogenation followed by a selective catalytic cracking, said selective catalytic hydrogenation being conducted to such an extent as to selectively hydrogenate aromatic compounds to naphthenic compounds, the catalyst of said selective cracking being silicalite molecular sieve with a pore diameter in at least one dimension between 4 and 7 Angstroms, by said selective catalytic cracking paraffins are converted to naphtha fractions boiling below the boiling range of said hydrogen donor solvent, separating the product from said catalytic treatment by a second distillation into a naphtha fraction boiling below 200° C. and a higher boiling fraction with a boiling range of 200° to 500° C., said higher boiling fraction being solely used as said hydrogen donor solvent, the bromine number of said hydrogen donor solvent being the same as the bromine number of the fraction boiling at 200° to 500° C. of the product of said selective hydrogenation.