Method for recovering valuable metals from waste hydrodesulfurization catalyst

摘要

PURPOSE:To easily separate and recover valuable metals in a waste catalyst using alumina as the carrier, such as No, Ni, Co, V, Al, etc., in high yields by calcining the waste catalyst, dissolving it into sulfuric acid together with the catalytic metals to be dissolved and subjecting the resulting solution to extraction sulfiding and adsorption successively. CONSTITUTION:The waste catalyst using the carrier consisting essentially of alumina is defatted and calcined at 400 to 1000 deg.c. The resulting calcined material is dissolved into sulfuric acid together with the catalytic metals to be dissolved to obtain the original solution to be extracted. This original solution is extracted with an organic Mo extractant and Mo is recovered from the Mo contg. organic phase of the Mo extractant. Then the residual solution resulting from the Mo extraction is extracted with an organic V extractant and V is recovered from the V contg. organic phase of the V extractant by stripping it out. Further the residual solution resulting from the V extraction is brought into contact with gaseous H2S and the Ni and Co in the solution are recovered as their sulfides. The minute amounts of Ni and Co in the finally recovered solution are adsorbed and recovered with a chelate resin to obtain a high purity aluminum sulfate solution. Then the Ni and Co adsorbed on the chelate resin are liberated from it with sulfuric acid and the liberated solution is repeatedly returned to the above reduction and dissolution processes.