title: Bifunctional resin-ZVI composites for effective removal of arsenite through simultaneous adsorption and oxidation.
abstract: Bifunctional resin-supported nanosized zero-valent iron (N-S-ZVI) composite was developed by combining the oxidation properties of nZVI/O2 with adsorption features of iron oxides and anion-exchange resin N-S. In batch culture experiments, N-S and the N-S-ZVI composite were examined for As(III) and As(V). The results reveal that ZVI in the composite played a key role in enhancing As(III) removal. The N-S-ZVI composites could oxidize more toxic As(III) to less toxic As(V) with high efficiency under ambient conditions without the need of noble metals. At the same time, the oxidized As(V) could be effectively removed by adsorption onto the surface of composites. The mechanisms for the oxidation of As(III) to As(V) and the simultaneous removal of As(V) are proposed. In order to investigate the potential performance of N-S-ZVI in practical use, the effects of solution pH and coexisting anions on arsenite removal and on fixed-bed column treatment of simulated waters were studied. All the results indicated that the bifunctional composites have a great potential for As(III) removal from contaminated waters.
authors: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China.
authors: Qiong
authors: Q
authors: Du
authors: Shujuan
authors: S
authors: Zhang
authors: Bingcai
authors: B
authors: Pan
authors: Lu
authors: L
authors: Lv
authors: Weiming
authors: W
authors: Zhang
authors: Quanxing
authors: Q
authors: Zhang
mesh_terms: D000327:Adsorption; D018053:Arsenites / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D018053:Arsenites; C015001:arsenite
keywords: Adsorption; Arsenite; Bifunctional composites; Oxidation; nZVI