Abstract: The multivalent metals of iron and chromium are removed by reducing the metal values to their lowest valence state by acidifying to a pH of below about 6 and adding an excess of hydrogen peroxide. The reduction is conducted at the foregoing pH value and in the presence of a sufficient amount of an organic compound which is a stronger reducing agent than the metal in its lowest valence state. Thereafter, a sufficient amount of a reactive metal hydroxide source is added to raise the pH above about 7 and to form a metal hydroxide with the metal in its lowest valence state. The resulting metal hydroxide is then easily removed from the aqueous effluent.