Hydrocracking utilises hydrogen gas and a catalyst to effect the conversion and separation of the residue feed stream into various products. Only the carbon-carbon bonds are broken and the hydrogen immediately saturates any olefins that are formed. Hydrocracking can produce LPG, naphtha, kerosene and distillates and the range of products depends on the type of feed to the unit.

The hydrocracking process requires high pressure – in the order of 80 – 140 barg. The operating temperature is in the range 340° – 420° C.