Removal of Arsenic from Water by Combination of Electro-Oxidation and Polymer Enhanced Ultrafiltration

摘要

Water-soluble poly[glycidyl methacrylate N-methyl d-gluca-mine], P(GMA-NMG), was synthesized and purified by ultra- filtration membranes. It was subsequently used for arsenic removal by coupling electro-oxidation (EO) and polymer- enhanced ultrafiltration (PEU) processes. In the EO-PEU combined process, P(GMA-NMG) was first used as supporting electrolyte during the exhaustive electro-oxidation of As(Ⅲ) to As(Ⅴ) and then it was used to remove As(Ⅴ) from aqueous solution through PEU. At first stage, the complete EO of As(Ⅲ) to As(Ⅴ) was performed with a platinum reticulated vitreous carbon (RVC)-modified electrode and the advance- ; ment of the electrolysis was monitored by analytical electro- des. After the oxidation of As(Ⅲ) to As(Ⅴ), the PEU was carried out by washing method using regenerate cellulose membrane and 1 bar of pressure. The effects of supporting electrolytes and pH on EO-PEU combined process were inves- tigated. The best results showed that by using P(GMA-NMG) as supporting electrolyte during the complete electro- oxidation of As(Ⅲ) to As(Ⅴ) followed by PEU separation, almost 80% of As(Ⅴ) was removed at pH 10.