Electricity Generation By Degradation Of Resistant Biodegradation Organic Pollutants Using A Microbial Fuel Cell

Microbial fuel cell (MFC) can promote the use of new energy attributable to its ability wastewaters treatment and generating electricity directly from the wastewater treatment.For toxic, resistant biodegradation organic wastewater treatment, a two-chambered MFC was designed in this research. Three kinds of phenolic compounds (p-nitrophenol,2,4-dichlorophenol,p-nitroaniline) were used as the substrates in the MFC that was inoculated with anaerobic sludge of municipal sewage plant, when connected1900Ω external resistor. In this paper, the feature of electricity production, phenolic compounds degradation and the growth of microorganisms during one cycle were studied in the two-chambered MFC.In the research, the two-chamber MFC was successfully started up using organic solvents which was self-made as the fuel. In order to study the performance of experimental devices, we using500mg/L glucose as the substrate in the MFC after started up, the power density of the two-chamber MFC was8.037mW/m2, and the internal resistance was1900Ω. When using the biodegradable organic matter (p-nitrophenol,2,4-dichlorophenol, p-nitroaniline) as the substrate of the MFC, the results showed that p-nitrophenol,2,4-dichlorophenol and p-nitroaniline could be used in the MFC for generating power and simultaneity degrading them in high efficiency. The power production cycle of the MFC was142,240,140hours when using p-nitrophenol,2,4-dichlorophenol and p-nitroaniline, respectively, as the sole substrate. When the influent concentration of them was100mg/L, MFC maximum output voltage values were139.2,385.5,262.9mV, the coulombic efficiency of MFC was0.671,4.74,1.178%, respectively. The capacity of microbial degradation of organic matter in the anode chamber was2,4-dichlorophenol<p-nitroaniline<p-nitrophenol. Adding a right amount of glucose, acetate and other easily degradable organic matter in the recalcitrant, toxic organic solution can not only enhance the degradation of resistant biodegradation organic matter, but also can improve the MFC power production capacity. The optimal added concentration was500mg/L, moreover, sodium acetate is more conductive to the degradation of refractory organic matter than glucose in the MFC. When a variety of resistant biodegradation organic matters as the mixed substrate (such as p-nitrophenol and2,4-dichlorophenol) in the MFC, p-nitrophenol was conductive to the MFC power production and the2,4-dichlorophenol degradation, the cycle of power generation was up to243hours, and the maximum voltage was401.1mV, the removal rate of p-nitrophenol and2,4-dichlorophenol were94.47%and 64.52%. We can see that the combination of different organic compounds can also improve the performance of MFC. After one electricity production cycle, the number of microorganisms in the anode chamber will increase greatly, which indicated that the microbes in the MFC can use anilines and nitrophenols as the carbon source for the proliferation. Using the domestication/screening of microorganisms as inoculums, the p-nitroaniline degradation rate increased from43.92%to54.75%, the maximum voltage increased from262.9mV to407.4mV. We can see that the dominant bacterium of MFC can improve the power generation and the degradation of organic matter.