标题：Enhanced paramagnetic Cu2+ions removal by coupling a weak magnetic field with zero valent iron
作者：Jiang, Xiao ;Qiao, Junlian ;Lo, Irene M.C. ;Wang, Lei ;Guan, Xiaohong ;Lu, Zhanpeng ;Zhou, Gongming ;Xu, Chunhua
作者机构：[Jiang, Xiao ;Qiao, Junlian ;Wang, Lei ;Guan, Xiaohong ;Zhou, Gongming ] State Key Laboratory of Pollution Control and Resources Reuse, College of Env 更多
来源：Journal of Hazardous Materials
摘要：A weak magnetic field (WMF) was proposed to enhance paramagnetic Cu2+ions removal by zero valent iron (ZVI). The rate constants of Cu2+removal by ZVI with WMF at pH 3.0-6.0 were -10.8 to -383.7 fold greater than those without WMF. XRD and XPS analyses revealed that applying a WMF enhanced both the Cu2+adsorption to the ZVI surface and the transformation of Cu2+to Cu0by ZVI. The enhanced Cu2+sequestration by ZVI with WMF was accompanied with expedited ZVI corrosion and solution ORP drop. The uneven distribution of paramagnetic Cu2+along an iron wire in an inhomogeneous MF verified that the magnetic field gradient force would accelerate the paramagnetic Cu2+transportation toward the ZVI surface due to the WMF-induced sharp decay of magnetic flux intensity from ZVI surface to bulk Cu2+solution. The paramagnetic Fe2+ions generated by ZVI corrosion would also accumulate at the position with the highest magnetic flux intensity on the ZVI surface, causing uneven distribution of Fe2+, and facilitate the local galvanic corrosion of ZVI, and thus, Cu2+reduction by ZVI. The electrochemical analysis verified that the accelerated ZVI corrosion in the presence of WMF partly arose from the Lorentz force-enhanced mass transfer.
© 2014 Elsevier B.V.