Removal of Heavy Metal Ions by Electrocoagulation for Continuous Useof Fe2+/Fe3+-Mediated Electrochemical Oxidation Solutions

Bulletin of the Korean chemical society

Myoungho Pyo¹  Youn Su Jung¹ 

关键词: Electrocoagulation;    MEO;    Metal ions;    Fe electrode;    Al electrode;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Removal of heavy metal ions (Cd2+ and Zn2+) by electrocoagulation (ECG) was investigated in an acidic condition, which is necessary for re-using or discharging the mediated electrochemical oxidation (MEO) media. Effects of various parameters such as electrolytes, current densities, and electrode materials were examined for a metal-contaminated MEO system using Fe2+/Fe3+ pairs as a mediator. It was found that ECG with Al electrodes is greatly affected by the presence of Fe2+. [Cd2+] and [Zn2+] remain constant until [Fe2+] reaches a certain concentration level (ca. 10 mM). This preferential removal of Fe2+ during ECG with Al electrodes is not alleviated by controlling current densities, potential programs, and solution mixing. ECG with Fe electrodes, on the other hand, resulted in relatively fast removal of Cd2+ and Zn2+ under coexistence of Fe2+, indicative of the different role between Fen+ generated from an electrode and Fe2+ initially present in a solution. When ECG was performed with Fe electrodes until [Fen+] became the same as the concentration of initially present Fe2+, [Cd2+] and [Zn2+] were reduced to one-tenth of the initial concentrations, suggesting the possibility of a continuous use of the medium for a subsequent MEO process.

【 授权许可】

Unknown