title: Novel reduction of Cr(VI) from wastewater using a naturally derived microcapsule loaded with rutin-Cr(III) complex.
abstract: The harmfulness of carcinogenic hexavalent chromium (Cr(VI)) is dramatically decreased when Cr(VI) is reduced to trivalent chromium (Cr(III)). Rutin, a natural flavonoid, exhibits excellent antioxidant activity by coordinating metal ions. In this study, a complex containing rutin and Cr(III) (rutin-Cr(III)) was synthesized and characterized. The rutin-Cr(III) complex was much easier to reduce than rutin. The reduction of the rutin-Cr(III) complex was highly pH-dependent, with 90% of the Cr(VI) being reduced to Cr(III) in 2h under optimal conditions. A biodegradable, sustained-release system encapsulating the rutin-Cr(III) complex in a alginate-chitosan microcapsule (rutin-Cr(III) ACMS) was also evaluated, and the reduction of Cr(VI) was assessed. This study also demonstrated that low-pH solutions increased the reduction rate of Cr(VI). The environmentally friendly microcapsules can reduce Cr(VI) for prolonged periods of time and can easily biodegrade after releasing the rutin-Cr(III) complex. Given the excellent performance of rutin-Cr(III) ACMS, the microcapsule system represents an effective system for the remediation of Cr(VI) pollution.
authors.affiliation: Tianjin Technological Engineering Center on Biomass-Derived Gas and Oil, Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin 300072, China. Electronic address: qiyun@tju.edu.cn.
authors.forename: Yun
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Tianjin Technological Engineering Center on Biomass-Derived Gas and Oil, Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin 300072, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 300193, China. Electronic address: cuiyl@tju.edu.cn.
authors.forename: Yuan-Lu
authors.initials: YL
authors.lastname: Cui
authors.affiliation: Tianjin Technological Engineering Center on Biomass-Derived Gas and Oil, Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin 300072, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Tianjin Technological Engineering Center on Biomass-Derived Gas and Oil, Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin 300072, China.
authors.forename: Shejiang
authors.initials: S
authors.lastname: Liu
mesh_terms: D002214:Capsules; D002857:Chromium / Q000737:chemistry*; D010084:Oxidation-Reduction; D012431:Rutin / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002214:Capsules; D002857:Chromium; D012431:Rutin; D062065:Wastewater; D014874:Water Pollutants, Chemical; C074702:chromium hexavalent ion
keywords: Alginate–chitosan microcapsule; Cr(VI) reduction; Flavonoid–metal complex; Rutin; Rutin–Cr(III)