Decomplexation and subsequent reductive removal of EDTA-chelated Cu-II by zero-valent iron coupled with a weak magnetic field: Performances and mechanisms

作者：Guan Xiaohong^*; Jiang Xiao; Qiao Junlian; Zhou Gongming

来源：Journal of Hazardous Materials, 2015, 300: 688-694.

DOI：10.1016/j.jhazmat.2015.07.070

• Cu-II-EDTA
• Fe-0/WMF
• Decomplexation
• Reduction
• Magnetic propeller agitator

The feasibility of EDTA-chelated Cu-II (Cu-II-EDTA) removal by zero-valent iron (Fe-0) in the presence of a weak magnetic field (WMF) and the involved mechanisms were systematically investigated. Fe-0 combined with WMF (Fe-0/WMF) was very effective for removing Cu-II-EDTA at pH 4.0-6.0 with the rate constants ranging from 0.1190 min(-1) to 0.0704 min(-1). Little passivation of Fe-0 was observed during Cu-II-EDTA removal by Fe-0/WMF in 8 consecutive runs when 10.0 mg L-1 Cu-II-EDTA was dosed before the initiation of each run. The evidences presented in this study verified that Cu-II-EDTA was removed by decomplexation followed by reduction/adsorption. In brief, Fe-II released from Fe-0 corrosion was rapidly oxidized by oxygen to Fe-II to chelate with EDTA and release free Cu-II, and the detached Cu-II ions were subsequently reduced/removed by Fe-0/Fe-II and co-precipitated by the generated iron (hydr)oxides. To advance the application of Fe-0/WMF technology in real practice, a magnetic propeller agitator was designed to offer WMF inside the reactor, which could greatly improve Cu-II-EDTA removal by Fe-0 and be easily amplified.

• 出版日期2015-12-30
• 单位同济大学