Process for reducing the Ramsbottom carbon test of asphalt

A process for the preparation of a hydrocarbon mixture having an RCT of (a) %w and an initial boiling point of T.degree. C., wherein an asphaltic bitumen obtained in the solvent deasphalting of a distillation residue from a crude mineral oil, which asphaltic bitumen has an RCT of (b) %w and an average molecular weight M, is subjected to a catalytic hydrotreatment in order to reduce the RCT;

• the product obtained is separated by distillation into an atmospheric distillate and an atmospheric residue having an initial boiling point of T.degree. C.;
• either so much asphaltic bitumen is separated from the atmospheric residue by solvent deasphalting that a deasphalted atmospheric residue having the desired RCT of (a) %w is obtained, or the atmospheric residue is separated by distillation into a vacuum distillate and a vacuum residue, from which vacuum residue so much asphaltic bitumen is separated by solvent deasphalting that a deasphalted vacuum residue is obtained which has such an RCT that, when it is mixed with the vacuum distillate, a mixture having the desired RCT of (a) %w is obtained;
• and the catalytic hydrotreatment is carried out under such conditions as to obey the relation:
• ##EQU6## where (c) is the RCT of the atmospheric residue having an initial boiling point T.degree. C. of the hydrotreated product.