Hydroconversion process

A process for the hydrocracking of heavy petroliferous stocks comprising

• (A) feeding (1) a petroleum stream boiling mainly above 400.degree. F. and (2) hydrogen to a distillation column reactor;
• (B) concurrently in said distillation column reactor
• (1) distilling said petroleum stream whereby there are vaporous petroleum products rising upward through said distillation column reactor, an internal reflux of liquid flowing downward in said distillation column reactor and condensing petroleum products within said distillation column reactor,
• (2) contacting said petroleum stream and said hydrogen in the presence of a hydrocracking catalyst at total pressure of less than about 300 psig, hydrogen partial pressure in the range of 1.0 to less than 70 psia and a temperature in the range of 400 to 1000.degree. F. whereby a portion of the petroleum stream is cracked to lighter products boiling below the boiling point of said petroleum stream and
• (3) distilling products in said column to remove a vaporous overhead stream comprising products mainly boiling below the boiling point of said petroleum stream and a liquid bottoms stream, the specific gravity and average molecular weight of the combined overhead stream and liquid bottoms stream being lower than that of petroleum stream, and
• (C) condensing a portion of the overheads and returning a portion of said condensed overheads to said distillation column reactor as external reflux.