Study On Driving Effect Of Microbial Fuel Cell On Migration Of Heavy Metals In Soil

The soil microbial fuel cell was constructed using soil contaminated with heavy metals cadmium and arsenic as a matrix,and its effect on soil MFC electricity generation performance was studied by controlling the types and concentration gradients of heavy metals in the soil,while focusing on the migration of heavy metals in soil.Explore whether microbial fuel cells have a driving effect on the migration of heavy metals in the soil.The stable voltages generated by soil MFC under four increasing concentration gradients in cadmium-contaminated soil were 195?205 mV(Cdl),180?190 mV(Cd2),180?190 mV(Cd3)and 175?185 mV(Cd4).The maximum power density were 11.3 mW/m2(Cd1),9.7 mW/m2(Cd2),9.6 mW/m2(Cd3)and 9.4 mW/m2(Cd4).The stable power generation voltage of the pollution-free control group was 195?205 mV.The maximum power density was 11.3 mW/m2.The soil MFC was operated for 30 days.Under different concentration gradients,the characteristics of the anode microbial community were somewhat different.The stable voltages generated by the soil MFC in the cadmium-arsenic compound contaminated soil under four increasing concentration gradients were 245?275 mV(FH1),210?240 mV(FH2),120?150 mV(FH3)and 115?145 mV(FH4).The maximum power density were 10.6 mW/m2(FH1),8.3 mW/m2(FH2),5.8 mW/m2(FH3)and 5.2 mW/m2(FH4).The stable power generation voltage of the pollution-free control group was 225?255 mV.The maximum power density was 9.4 mW/m2.The soil MFC has been running for 40 days.Under different concentration gradients,the characteristics of the anode microbial community are significantly different.The concentrations of heavy metals cadmium and arsenic in each layer of soil increased in sequence with the increase of soil depth,but the increase in concentration was smaller than that of the control group.The above shows that the soil microbial fuel cell can drive cathode to both cadmium and arsenic in the soil.