The Application Of Redox Mediator In Microbial Fuel Cells

Nitrate wastewater mainly comes from the use of agricultural fertilizer,the emissions of sewage and industrial wastewater.After a large number of nitrate wastewater flow into the land,rivers which were polluted.Microbial fuel cell(MFC)as a new wastewater treatment technology in the degradation of pollutants at the same time generate electricity.It has become a hotspot.On the basis,the experimental investigation of MFC performance optimization,the effect of redox mediators and modified electrodes on the performance of it.MFCs were successfully started by synthetic wastewater.After successfully starting,the four factors of carbon source,C/N,nitrate concentration and temperature were optimized,The results showed that sodium acetate as carbon source,C/N of 5:1and200mg/L nitrate concentration,30 ? respectively.Furthermore,the degradation rate of nitrate reached more than 90 percent and the voltage of MFC was 0.462 V.Sulfur,neutral red,anthraquinone-2,6-disulfonic acid sodium,anthraquinone-2-sodium sulfonate,anthracene ketone,resazurin,methylene blue seven different redox mediators were added in order to investigate the effect of redox mediators on the performance of MFCs..The electric energy output resazurin improve largest,when the concentration of resazurin was 1?mol/L,1h nitrate removal rate was 90 percent,the anthraquinone-2,6-disulfonic acid sodium concentration of 1 ?mol/L when its 302 m V maximum power output,the rest of the fixator on MFC performance also have different degrees of role.The experiment also examines the redox mediators modified electrodes effects on MFC.The results showed that the anthraquinone-2,6-disulfonic acid sodium doping pyrrole modified electrodes and microbial fuel cell of diazo reaction modified electrodes its maximum power output can reach 200 mV and 179 mV,respectively,and 30 days running water nitrate,COD removal rate is above 97 percent.Analysis this method may be the introduction of amide groups,the groups can effectively promote the interaction between microorganisms and electrode,thus to increase the microbial quantity in attached on the surface of the electrode,thus increasing the MFC electricity production effect.