| As an alternative to alleviate the energy crisis and solve the environmentalproblems, microbial fuel cell (MFC) can generate electricity directly from thetreatment of wastewater and has become one of the focuses in the field ofenvironmental protection and energy recovery. In this paper, a two-chamberMFC with oxygen or 4-chlorophenol (4-CP) as oxidant was operated with acetateas fuel to investigate its performance of electricity production and ability ofwastewater treatment. The experiment results are listed below:1. Biofilm was formed on the surface of anode during the startup process ofMFC. Using a carbon fibre with pre-attached biofilm as anode couldremarkably shorten the startup process. For inoculation sludge, anaerobicsludge was more suitable than treated aerobic sludge. After two weeks'cultivation, lots of bacteria, mainly bacillus, was attached onto the surface ofcarbon fibre.2. The acetate initial concentration of 200 mg/L was the optimum fuel load forthis MFC. Increasing the concentration of electrolyte could reduce theinternal resistance of MFC, and improve the power generation ability. LowerpH of cathodic solution was better for cathodic reaction. Air rate of 1.44m3(m2·h) in cathode chamber was the optimum condition for this MFC.Purging N2 into anode chamber could improve the mass transfer in thischamber and effectively prevent oxygen from influence the growth ofmicroorganisms.3. When carbon fibre with Pt, activated carbon fibre, HNO3 modified carbonfibre, or gas diffusion electrode was applied as cathode instead of carbonfibre, the maximum power density of MFC improved 4.8 times, 3.2 times, 2times, and 2 times respectively.4. MFC with 4-CP as oxidant had good electricity generation ability, whosemaximum power density reached 12.4 mW/m2 and columbic efficiencyachieved 22.7％with 4-CP initial concentration of 60 mg/L. Simultaneously,this MFC had good degradation ability for 4-CP, since 4-CP could becompletely dechlorinated in 45 h.
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