Abstract:
A hydrocracking process wherein heavy hydrocarbon oils having from about 10 to 50 percent boiling above 1,000*F. and containing appreciable amounts of sulfur, nitrogen, and metal-containing compounds as well as asphaltenes are converted into a minor fraction of low sulfur residual fuel oil and a major fraction of low sulfur gasoline. The process comprises hydrocracking the heavy oil with molecular hydrogen, at a temperature of about 700*-850*F. in the presence of a sulfur and nitrogen resistant hydrocracking catalyst comprising a hydrogenating component supported upon an amorphous inorganic oxide cracking base to convert the heavy hydrocarbon oil into a gas-oil fraction and a low sulfur residual fraction; separating the gas-oil fraction from the residual fraction; hydrocracking the gas-oil fraction with molecular hydrogen, at a temperature of 700*-780*F., in the presence of a sulfur and nitrogen resistant hydrocracking catalyst comprising a hydrogenation component supported upon a cation exchanged crystalline silica-alumina zeolitic molecular sieve cracking base to yield low sulfur, low nitrogen gasoline.