Method for recovering noble metals from metallic carrier catalytic device

Abstract

This invention provides a method for efficiently separating and recovering a wash coat which supports noble metal-containing catalytic component from a metallic carrier of a spent metallic carrier catalytic device for such purposes as the purification of exhaust gas from internal combustion engine, without substantially crushing or dissolving said metallic carrier, which method comprises subjecting a metallic carrier catalytic device which is composed of a metallic carrier having a wash coat provided thereon and a noble metal-containing catalytic component which is supported on the wash coat to a treatment with an aqueous solution of mixed acid which contains sulfuric acid and nitric acid.

Dependencies are inferred from the claim text.