摘要
构建三室土壤微生物燃料电池(MFCs),通过添加不同浓度的柠檬酸,研究其对土壤中重金属去除的影响。研究结果表明:当柠檬酸浓度由0 mol·L^(-1)增加到1 mol·L^(-1)时,MFC的内阻显著降低,土壤的pH显著下降,且从阳极到阴极下降的趋势越明显,但电导率逐渐升高;柠檬酸的投加浓度与内阻呈显著线性相关,拟合优度R^(2)=0.927,这极大地提高了MFC的产电性能,MFC的最大输出电压由0.439 V增加到0.517 V,最大功率密度由0.75 W·m^(-3)增加到0.99 W·m^(-3),同时,随着柠檬酸浓度的升高,土壤中乙酸提取态Cu质量分数不断升高,说明重金属可移动性显著提高,这有利于土壤中的Cu在MFC内部电场中的迁移去除;当柠檬酸投加浓度为1 mol·L^(-1)时,MFC土壤室的总Cu去除量最大为66.58 mg,去除率最大达到37.03%;随着柠檬酸浓度的提高,电极片上的沉积物分布越密集,还原产物含量越高;部分迁移至阴极的Cu离子被还原为单质Cu沉积在阴极片上。
A three-chamber soil microbial fuel cells(MFCs) was constructed. By adding different concentrations of citric acids, its influence on the removal of heavy metals in soil was studied. The results show that when the concentration of citric acid increases from 0 mol·L^(-1) to 1 mol·L^(-1) , the internal resistance of MFC is significantly reduced, the pH of the soil is significantly reduced, and the downward trend is more obvious from anode to cathode, but the electrical conductivity gradually increases. The concentration of citric acid is significantly linearly related to the internal resistance, R^(2)=0.927, which significantly improves the power generation performance of MFC, and the maximum output voltage of MFC increases from 0.439 V to 0.517 V, and the maximum power density of MFC increases from 0.75 W·m^(-3) to 0.99 W·m^(-3) . At the same time, as the concentration of citric acid increases, the acetic acid-extracted Cu mass fraction in the soil continues to increase, which represents a significant increase in the mobility of heavy metals, and which is conducive to the migration and removal of Cu in the internal electric field of the MFC. When the concentration of citric acid is added to 1 mol·L^(-1) , the maximum Cu removal is 66.58 mg and the total Cu removal rate of the MFC soil chamber is up to 37.03%. With the increase of the the concentration of citric acid, the more dense the distribution of deposits on the cathode sheet is, the higher the content of the reduction products is. Part of the Cu ions migrated to the cathode are reduced to elemental Cu and deposit on the cathode sheet.
作者
孙艺伦
张婧然
朱丹丹
李先宁
SUN Yilun;ZHANG Jingran;ZHU Dandan;LI Xianning(School of Energy and Environment,Southeast University,Nanjing 210096,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2021年第10期3397-3404,共8页
Journal of Central South University:Science and Technology
基金
国家水体污染控制与治理科技重大专项(2017ZX07202004-005)
江苏省自然科学基金资助项目(BK20171351)。
关键词
微生物燃料电池
柠檬酸
重金属污染
产电性能
迁移去除
microbial fuel cells
citric acid
heavy metal pollution
power generation performance
migration and removal
