Adsorption of As(V)/As(III) on TiO2 and the Photocatalytic Oxidation of As(III)
نویسنده
چکیده
INTRODUCTION A great deal of attention has been given in the last two decades to the oxidative photocatalytic degradation of organic contaminants using TiO2 [1-7]. The photo-oxidation of As(III) to As(V) in aqueous solution and the influence of light intensity has not yet been extensively studied inspite of the fact that this reaction might be useful to enhance removal of arsenic from drinking water. This study focuses on surface-catalyzed As(III) oxidation by TiO2 and the influence of light intensity, pH, and TiO2 mineralogy (anatase and rutile) on reaction kinetics. In addition, the comparative adsorption behaviors of As(III) and As(V) on rutile and anatase, including the effect of solution pH, was investigated.
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