A hydrocarbonaceous feed, such as petroleum vacuum distillation bottoms, is upgraded by a combination coking and catalytic slurry hydroconversion process wherein a bottoms fraction from coking is passed through a microfiltration system to remove coke fines, the filtrate passed to a slurry hydroconversion zone, and the bottoms fraction from the slurry hydroconversion zone is also passed through a microfiltration system to remove catalyst particles.