title: Enhanced dechlorination of 2,4-dichlorophenol by recoverable Ni/Fe-Fe3O4nanocomposites.
abstract: Ni/Fe-Fe3O4nanocomposites were synthesized for dechlorination of 2,4-dichlorophenol (2,4-DCP). The effects of the Ni content in Ni/Fe-Fe3O4nanocomposites, solution pH, and common dissolved ions on the dechlorination efficiency were investigated, in addition to the reusability of the nanocomposites. The results showed that increasing content of Ni in Ni/Fe-Fe3O4nanocomposites, from 1 to 5wt.%, greatly increased the dechlorination efficiency; the Ni/Fe-Fe3O4nanocomposites had much higher dechlorination efficiency than bare Ni/Fe nanoparticles. Ni content of 5wt.% and initial pH below 6.0 was found to be the optimal conditions for the catalytic dechlorination of 2,4-DCP. Both 2,4-DCP and the intermediate product 2-chlorophenol (2-CP) were completely removed, and the concentration of the final product phenol was close to the theoretical phenol production from complete dechlorination of 20mg/L of 2,4-DCP, after 3hr reaction at initial pH value of 6.0, 3g/L Ni/Fe-Fe3O4, 5wt.% Ni content in the composite, and temperature of 22°C. 2,4-DCP dechlorination was enhanced by Cl-and inhibited by NO3-and SO42-. The nanocomposites were easily separated from the solution by an applied magnetic field. When the catalyst was reused, the removal efficiency of 2,4-DCP was almost 100% for the first seven uses, and gradually decreased to 75% in cycles 8-10. Therefore, the Ni/Fe-Fe3O4nanocomposites can be considered as a potentially effective tool for remediation of pollution by 2,4-DCP.
authors.affiliation: Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China. Electronic address: xucancan523127@163.com.
authors.forename: Cancan
authors.initials: C
authors.lastname: Xu
authors.affiliation: Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China. Electronic address: liuruitsinghuazj@gmail.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China; School of Environment, Tsinghua University, Beijing 100084, China. Electronic address: chenlj@tsinghua.edu.cn.
authors.forename: Lvjun
authors.initials: L
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China.
authors.forename: Jialu
authors.initials: J
authors.lastname: Tang
mesh_terms: D002733:Chlorophenols / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005296:Ferrous Compounds / Q000737:chemistry*; D054879:Halogenation; D053761:Nanocomposites / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002733:Chlorophenols; D005296:Ferrous Compounds; D014874:Water Pollutants, Chemical; D009532:Nickel; C034236:ferrous oxide; C004762:2,4-dichlorophenol
keywords: 2,4-Dichlorophenol; Catalytic dechlorination; Common dissolved ions; Ni/Fe-Fe(3)O(4) nanocomposites; Recoverable