Organically polluted waters are purified by contacting with a solid copper-manganese-oxygen catalyst promoted with at least one Group II metal under oxidizing conditions. In one preferred embodiment, an aqueous stream obtained from the effluent of an oxidative dehydrogenation process containing contaminating oxygen-containing organic materials is subjected to oxidizing conditions in the presence of a copper manganite catalyst promoted with at least one Group II metal to convert the water to an aqueous product.