三室土壤MFC修复Cu污染土壤的模拟研究

Simulation study on remediation of Cu-contaminated soil by three-chamber soil microbial fuel cell

在三室土壤微生物燃料电池(MFC)中研究Cu质量分数和辅助剂对MFC产能和Cu迁移及去除的影响。研究结果表明:随着Cu质量分数从100.00 mg/kg增加到500.00 mg/kg,MFC的产能显著增加,最大功率密度从9.92 mW/m^2增加到59.67 mW/m^2,去除率从13.85%增加到28.21%;与盐酸(HCl)和乙酸(HAC)相比,柠檬酸(CA)的脱附效果最佳,酸可提取态Cu质量分数占总Cu质量分数的84.00%,但添加HCl的MFC具有更高的电导率和产能,同时,土壤中Cu的迁移去除率最高(40.03%);MFC中重金属主要在电迁移作用下实现了向阴极迁移,经MFC修复后,土壤中Cu质量分数从阳极到阴极呈现先上升后下降趋势;初始酸可提取态Cu质量分数与土壤pH呈显著负相关(相关系数R2=0.96),总Cu去除率与土壤电导率呈正相关(R^2=0.91);MFC更适用于修复受重金属污染较严重的土壤,且向土壤中添加HCl可以促进土壤中Cu的迁移去除。

A three-chamber soil microbial fuel cell(SMFC)was used to study the electricity generation performance of MFC,and the migration and removal mechanism of Cu at different mass fractions of Cu and desorbents in soil.The results show that as Cu mass fraction increases from 100.00 mg/kg to 500.00 mg/kg,the production capacity of MFC increases significantly,the maximum power density increases from 9.92 mW/m2 to 59.67 mW/m2,and the removal rate increases from 13.85%to 28.21%.Compared with hydrochloric acid(HCl)and acetic acid(HAC),citric acid(CA)has the best desorption effect,and the acid-extractable Cu mass fraction accounts for 84.00%.But HCl-added MFC has higher conductivity and productivity,and the removal rate of total Cu in soil is the highest(40.03%).The heavy metals in MFC mainly migrate to the cathode under the action of electromigration.After operation,the Cu mass fraction in the soil increases first and then decreases from the anode to the cathode.The initial acid extractable Cu mass fraction is significantly negatively correlated with soil pH(R2=0.96),and the total Cu removal rate is positively correlated with soil electrical conductivity(R2=0.91).MFC is more suitable for remediation of soils heavily polluted by heavy metals,and the addition of HCl to the soil can promote the removal of Cu from the soil.