title: The role of Cu(II) in the reduction of N-nitrosodimethylamine with iron and zinc.
abstract: The role of Cu(II) in the reduction of N-nitrosodimethylamine (NDMA) with zero-valent metals was investigated by determining the effects of Cu(II) on the removal, kinetics, products, and mechanism. NDMA removal was enhanced, and all reactions followed a pseudo-first-order kinetic model except for the Fe and Fe/0.1 mM Cu(II) systems. The iron mass-normalized pseudo-first-order rate constants (kMFe) increased with the Cu(II) concentration. The zinc mass-normalized pseudo-first-order rate constants (kMZn) were identical to those with the Cu(II) concentrations from 0.1 mM to 1.0 mM and were higher with 2.0 mM Cu(II). The types of products detected were unchanged. Some unknown products were also found. NDMA was reduced to 1,1-dimethylhydrazine (unsymmetrical dimethylhydrazine, UDMH). Then, UDMH was reduced into dimethylamine (DMA) by the Fe/Cu(II) and Zn/Cu(II) systems. Catalytic hydrogenation was proposed as the reduction mechanism. Several copper species, such as Cu(OH)2in the Fe/Cu(II) system and Cu2O and Cu(OH)2in the Zn/Cu(II) system enhanced NDMA reduction. Differences between the Fe/Cu(II) and Zn/Cu(II) systems were caused by the reduction potentials and surface conditions of the different metals and the copper species in the various systems.
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China. Electronic address: yinghan@zjut.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Zhong-Lin
authors.initials: ZL
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Ji-Min
authors.initials: JM
authors.lastname: Shen
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China.
authors.forename: Ji-He
authors.initials: JH
authors.lastname: Wang
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Li
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Bin-Yuan
authors.initials: BY
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Tong
mesh_terms: D003300:Copper / Q000737:chemistry*; D004123:Dimethylamines / Q000737:chemistry; D004127:Dimethylhydrazines / Q000737:chemistry; D004128:Dimethylnitrosamine / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification; D015032:Zinc / Q000737:chemistry*
chemical_list: D004123:Dimethylamines; D004127:Dimethylhydrazines; D014874:Water Pollutants, Chemical; C013958:dimazine; D003300:Copper; C034516:dimethylamine; D007501:Iron; D015032:Zinc; D004128:Dimethylnitrosamine
keywords: Cu(II); Iron; N-Nitrosodimethylamine; Reduction; Zinc