School of Energy and Environment, Southeast University, Nanjing, 210096, China.
School of Energy and Environment, Southeast University, Nanjing, 210096, China; Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Aramaki 6-6-06, Sendai, 980-8579, Japan.
Ecotoxicol Environ Saf. 2020 Apr 1;192:110314. doi: 10.1016/j.ecoenv.2020.110314. Epub 2020 Feb 13.
As an environmentally sustainable bioelectrochemical technology, the microbial fuel cell (MFC) has attracted great attention. In this study, a three-chamber MFC (TC-MFC) was enhanced with different auxiliary reagents to remove heavy metals from soil. The results showed that the removal efficiency of heavy metals from soil increased with increasing auxiliary reagent concentration. When 1 mol/L citric acid, HCl, or acetic acid were used as an auxiliary reagent, the total copper (500 mg/kg) removal efficiency after 74 days of TC-MFC treatment was 3.89, 5.01 and 2.01 times that of the control group, respectively. The highest soil electrical conductivity (15.29 ms/cm), ionic heavy metal content (94.78%), electricity generation performance (363.04 mW h), and desorption stability of heavy metals were obtained when using 1 mol/L HCl as an auxiliary reagent, indicating that HCl was more suitable for the remediation of heavy metals in soil using a TC-MFC. Correlation analysis showed that the electricity generation of the TC-MFC was linearly related to the removal efficiency of heavy metals from soil (R = 0.9296). At the same time, higher content of ionic heavy metals in the soil led to better migration of heavy metals under the internal electric field of the TC-MFC.
作为一种环境可持续的生物电化学技术，微生物燃料电池 (MFC) 引起了极大的关注。本研究采用三室 MFC (TC-MFC) 强化法，使用不同的辅助试剂来去除土壤中的重金属。结果表明，随着辅助试剂浓度的增加，土壤中重金属的去除效率也随之提高。当 1mol/L 的柠檬酸、HCl 或乙酸作为辅助试剂时，TC-MFC 处理 74 天后，总铜（500mg/kg）的去除效率分别是对照组的 3.89、5.01 和 2.01 倍。使用 1mol/L HCl 作为辅助试剂时，土壤电导率（15.29ms/cm）最高、离子态重金属含量（94.78%）最高、发电性能（363.04mWh）最高、重金属解吸稳定性最高，表明 HCl 更适合 TC-MFC 修复土壤中的重金属。相关性分析表明，TC-MFC 的发电与土壤中重金属的去除效率呈线性相关（R=0.9296）。同时，土壤中离子态重金属含量越高，在 TC-MFC 的内部电场作用下，重金属的迁移性越好。
