title: Kinetics and mechanisms of amorphous FeS2induced Cr(VI) reduction.
abstract: A novel reductant, amorphous FeS2(FeS2(am)) was synthesized to remove hexavalent chromium (Cr(VI)). The stoichiometry, kinetics and mechanisms of FeS2(am)induced Cr(VI) reduction were studied under anaerobic conditions with a pH range of 5.0-13.0. Results showed that FeS2(am)was efficient in removing aqueous Cr(VI) with a stoichiometry of Cr(VI): FeS2(am)∼1: 0.9. Moreover, the reduction kinetics decreased with the growth of pH within the pH range from 5.0 to 10.0, but increased within pH 10.0-13.0. The dissolution kinetics of FeS2(am)was found to be mainly responsible for the varied Cr(VI) reduction kinetics, and the mechanisms involved in the reduction process were further confirmed by X-ray photoelectron spectroscopy analysis. In addition, O2was found to compete with Cr(VI) in the reduction process and subsequently impede the Cr(VI) reduction rate.
authors.affiliation: College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China.
authors.forename: Yunyi
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Liang
authors.affiliation: College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China.
authors.forename: Xiao
authors.initials: X
authors.lastname: He
authors.affiliation: College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Environmental Sciences and Engineering, Peking University, Beijing Key Laboratory for Solid Waste Utilization and Management, 100871, PR China. Electronic address: yshliu@pku.edu.cn.
authors.forename: Yangsheng
authors.initials: Y
authors.lastname: Liu
keywords: Amorphous FeS(2); Hexavalent chromium; Kinetics; Mechanism; Stoichiometry