Method for seperating V W and Ti components from waste de-Nox catalyst

摘要

PURPOSE: A process for separating and recovering metals such as titanium, vanadium and tungsten from waste deNOx catalyst having principal constituents of titanium, vanadium and tungsten effectively and economically is provided. CONSTITUTION: The method comprises a step of selectively eluting vanadium and tungsten only in an aqueous solution phase from waste deNOx catalyst containing 70 to 90 wt.% of TiO2, 1 to 10 wt.% of V2O5 and 10 to 20 wt.% of WO3 through leaching process using at least one alkali solution selected from NaOH, KOH, NH4OH and Ca(OH)2 solutions, and recovering titanium oxide that is not eluted in a solid phase through filtering process; and a step of recovering the vanadium and tungsten eluted in the aqueous solution phase as vanadium oxide and tungsten oxide, wherein the vanadium and tungsten eluted in the aqueous solution phase are separated by precipitation, solvent extraction or a combination thereof, wherein concentration of alkali solution used in the leaching process is 0.1 N or more, and a consumption amount of the alkali solution is at least 2 times or more of a stoichiometrically required amount, and wherein the titanium oxide recovered in a solid phase is reused as raw material for deNOx catalyst, filler, building admixture or TiO2 photocatalyst raw material.