METHOD FOR ARSENIC REMOVAL FROM WASTEWATER

摘要

METHOD FOR ARSENIC REMOVAL FROM WASTEWATER A process and apparatus for removing arsenic from aqueous media is described. The process in general utilizes ferrous ion provided by an electrochemical cell which is added to the aqueous media in a first step, followed by mild oxidizing conditions generated by the addition of hydrogen peroxide. The ferrous ion then forms an hydroxide which is oxidized to an oxyferric oxide and the arsenic present at a +3 oxidation state is oxidized to a +5 state whereupon the oxyacid complexes with the oxyferric oxide. A precipitate then is formed which consists of ferric arsenate, and the hydroxy ferric oxide - oxyacid complex. Heavy metals may also be removed by the process.