A modified EK method with an I-/I-2 lixiviant assisted and approaching cathodes to remedy mercury contaminated field soils

作者：Shen, Zhemin^*; Zhang, Jianda; Qu, Liya; Dong, Zeqin; Zheng, Shenshen; Wang, Wenhua

来源：Environmental Geology, 2009, 57(6): 1399-1407.

DOI：10.1007/s00254-008-1418-6

• Soil
• Pollution
• Electrokinetic remediation
• Mercury

Wanshan mercury mine is the largest cinnabar deposit in Guizhou, China. Few effective methods had been achieved to remedy Hg heavily contaminated field soils. In this paper, a modified EK method with approaching cathodes (AC-EK) and an I-/I-2 lixiviant was described to remedy mercury-contaminated field soils near Wanshan mercury mine. Paddy Soil I and Paddy Soil II were sampled and contained 576.73 +/- A 45.50 and 491.35 +/- A 4.73 mg/kg Hg, respectively. Although they contained 6.9 and 9.4% organic matter respectively, more than 92 and 89% Hg were removed by AC-EK within 5 days. Removal ratio increased by 0.21 and 0.68 times using EK process with ACs over that with one single cathode (SC-EK). AC-EK method saved nearly 26.4-28.1% electric power as compared to SC-EK method. As an I-/I-2 lixiviant solution was used to solubilize HgS(HgO) during EK process, the bonding of Hg to organic functional S groups should be less important than the binding to inner sites of organic matter in soil. The relationship between EK remediation effect and soil organic matter content was fitted to a linear model. It turned out that when soil OM increased by 1.0%, EK removal ratio (%) of Hg would decrease by 2.63%.

• 出版日期2009-5
• 单位上海交通大学; 贵州省环境科学研究设计院