Process for reducing ramsbottom carbon test of long residues

摘要

Process for the preparation of a heavy oil with a low Ramsbottom Carbon Test (RCT) from a long residue by (a) catalytic hydrotreatment for RCT reduction at such severity that the C.sub.4.sup.- gas production per percentage RCT reduction is kept between defined limits, followed by (b) solvent deasphalting of the (vacuum or atmospheric) distillation residue of the hydrotreated product.