Process for reducing ramsbottom carbon test of asphalt

摘要

In the preparation of a heavy oil with a low Ramsbottom Carbon Test (RCT) from a precipitation asphalt by a two-stage process comprising catalytic hydrotreatment followed by solvent deasphalting and recycle of the separated asphalt to the first stage, the catalytic hydrotreatment for RCT reduction in the first stage is carried out at such severity that the C.sub.4.sup.- gas production per percent RCT reduction is kept between defined limits.