The recovery of coal liquefaction catalysts.

摘要

Metal constituents are recovered from the heavy bottoms produced during the liquefaction of coal and similar carbonaceous solids in the presence of a catalyst containing a metal capable of forming an acidic oxide by burning the heavy bottoms in a combustion zone at a temperature below the fusion temperature of the ash to convert insoluble metal-containing catalyst residues in the bottoms into soluble metal-containing oxides; contacting the oxidized solids with an aqueous solution of a basic alkali metal salt to extract the soluble metal-containing oxides in the form of soluble alkali metal salts of the metal-containing oxides and recycling the soluble alkali metal salts to the liquefaction zone. In a preferred embodiment of the invention, the bottoms are subjected to partial oxidation, pyrolysis, coking, gasification, extraction or a similar treatment process to recover hydrocarbon liquids and/or gases prior to the burning or combustion step.