title: Effects of particle composition and environmental parameters on catalytic hydrodechlorination of trichloroethylene by nanoscale bimetallic Ni-Fe.
abstract: Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene (TCE), one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodechlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25°C. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20°C. Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts.
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: weijj@mail.buct.edu.cn.
authors: Jianjun
authors: J
authors: Wei
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Yajing
authors: Y
authors: Qian
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Wenjuan
authors: W
authors: Liu
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Lutao
authors: L
authors: Wang
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Yijie
authors: Y
authors: Ge
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Jianghao
authors: J
authors: Zhang
authors: Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
authors: Jiang
authors: J
authors: Yu
authors: Department of Civil and Environmental Engineering, Southern Illinois University Carbondale, Carbondale, IL 62901, United States. Electronic address: ma@engr.siu.edu.
authors: Xingmao
authors: X
authors: Ma
mesh_terms: D002384:Catalysis; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D009532:Nickel / Q000737:chemistry*; D014241:Trichloroethylene / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D014874:Water Pollutants, Chemical; D014241:Trichloroethylene; D009532:Nickel; D007501:Iron
keywords: catalytic dechlorination; composition; environmental parameters; hydrodechlorination; nanoscale Ni-Fe; trichloroethylene