title: Synergetic Transformations of Multiple Pollutants Driven by Cr(VI)-Sulfite Reactions.
abstract: Reduction of Cr(VI) is often deemed necessary to detoxify chromium contaminants; however, few investigations utilized this reaction for the purpose of treating other industrial wastewaters. Here a widely used Cr(VI)-sulfite reaction system was upgraded to simultaneously transform multiple pollutants, namely, the reduction of Cr(VI) and oxidation of sulfite and other organic/inorganic pollutants in an acidic solution. As(III) was selected as a probe pollutant to examine the oxidation capacity of a Cr(VI)-sulfite system. Both (•)OH and SO4(•-) were considered as the primary oxidants for As(III) oxidation, based on the results of electron spin resonance, fluorescence spectroscopy, and specific radicals quenching. As(III)-scavenging, oxidative radicals greatly accelerated Cr(VI) reduction and simultaneously consumed less sulfite. In comparison with a Cr(VI)-H2O2 system with 50 μM Cr(VI), Cr(VI), the sulfite system had excellent performance for both As(III) oxidation and Cr(VI) reduction at pH 3.5. Moreover, in this escalated process, less sulfite was required to reduce Cr(VI) than the traditional Cr(VI) reduction by sulfite process. This effectively improves the environmental compatibility of this Cr(VI) detoxification process, alleviating the potential for SO2 release and sulfate ion production in water. Generally, this study provides an excellent example of a "waste control by waste" strategy for the detoxification of multiple industrial pollutants.
authors.affiliation: State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, Shandong, P.R. China.|School of Environmental and Municipal Engineering, Qingdao University of Technology , Qingdao 266033, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, Shandong, P.R. China.
authors.forename: Yukun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, Shandong, P.R. China.
authors.forename: Jingtang
authors.initials: J
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, Shandong, P.R. China.
authors.forename: Minghui
authors.initials: M
authors.lastname: Tan
authors.affiliation: College of Environmental Science and Engineering, Donghua University , Shanghai, 201620, China.|Southern Cross GeoScience, Southern Cross University , Lismore, NSW 2480, Australia.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, Shandong, P.R. China.
authors.forename: Mingbo
authors.initials: M
authors.lastname: Wu
mesh_terms: D002857:Chromium / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D013447:Sulfites / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002857:Chromium; D006861:Hydrogen Peroxide; D016877:Oxidants; D013447:Sulfites; D062065:Wastewater; D014874:Water Pollutants, Chemical; C074702:chromium hexavalent ion