Additive for the hydroconversion of a heavy hydrocarbon oil

摘要

There is provided an additive for the hydroconversion of a heavy hydrocarbon oil, which is obtained by suspending a fine powder of a carbonaceous substance and a solution of a heteropolymolybdic acid and/or transition metal salts thereof in a hydrocarbon oil. By the use of the additive of the present invention, the hydroconversion of a heavy hydrocarbon oil can be effectively performed at high conversion without occurrence of coking.