| 초록 |
Arsenite [As(III)] and arsenate [As(V)] are highly toxic aquatic contaminants that pose a potential threat to the environment and human health. They are characterized by different chemical behavior, bioavailability, and toxicity. It is known that the arsenite is ca. 60 times more toxic and more mobile than arsenate. Therefore, the oxidation of arsenite to arsenate is desirable in order to reduce the arsenic toxicity while facilitating its removal from water supply. We performed the photocatalytic oxidation of arsenite in TiO2 suspension in this study. The effects of pH, humic acids(HA), and ferric ions on the arsenite oxidation kinetics were investigated in detail. Arsenite oxidation was enhanced in the alkaline condition than in the acidic one. The addition of HA and ferric ions at pH 3 greatly increased the photocatalytic oxidation rate of arsenite. nce Fe3+ and HA effectively enhanced the photocatalytic oxidation of arsenite, the arsenic contaminated groundwater that often contains high concentration of iron or organic matter could be readily remediated by the photocatalytic method. |
