Involute the reactivity of persulfate with zero-valent iron for enhanced removal of arsenic (V) in aspect involvement of Fe2+ or Fe3+

Abstract

Being a fundamental issue regarding sewage treatment, heavy metals removal from industrial effluents has been subject to intense scrutiny in both the academic and practical worlds. The removal of pentavalent arsenic (As(V)), one of the most poisonous pollutants, was investigated using a sodium persulfate and iron powder system activated by ferrous ions (Fe2+-ZVI-PS). As(V) could be effectively removed by an Fe2+-ZVI-PS system in a timely fashion (minute scale) with high removal rates (more than 90.0%) over a wide range of pH (1-9) and concentration (20-100 mg/L). The removal of As(V) by the Fe2+-ZVI-PS system integrated favorably with the pseudo-second-order reaction kinetics. Researches on X-ray photoelectron spectroscopy (XPS) demonstrated that the Fe2+-ZVI-PS system enables the removal of As(V) through the process of co-precipitation and adsorption. Our findings thus emphasized that the Fe2+-ZVI-PS system should be an effective trigger to purifying arsenic from the environment. Our results indicated that the Fe2+-ZVI-PS system could be an effective candidate for remediation of arsenic in the environment.