Abstract: A process for producing liquid and, optionally, gaseous products from gaseous reactants comprises feeding gaseous reactants into a slurry bed of solid particles suspended in a liquid; allowing the reactants to react as they pass upwardly through the slurry bed, thereby to form liquid and, optionally, gaseous products; and separating liquid product from the solid particles by passing, in a filtration zone within the slurry bed, liquid product through a filtration medium in a first direction, so that a cake of the solid particles forms on the filtration medium. The passage of liquid product through the filtering medium is interrupted. The filtering medium is then backflushed by passing a flushing fluid through the filtering medium in a second direction, opposite to the first direction, for at least portions of the periods that the liquid product passage is interrupted, thereby to dislodge the cake from the filtering medium.