Effect of in-situ immobilized anode on performance of the microbial fuel cell with high concentration of sodium acetate

To improve performance of the microbial fuel cell (MFC) with high concentration of organics, a procedure for in-situ immobilized anode with agarose gel was proposed in this study. The performance of power generation, electrochemical activity, and microbial community of the MFC with immobilized anode (i-MFC) was investigated using different concentrations (i.e., 1, 5, 10, and 20 g/L) of sodium acetate. The i-MFC could generate electricity within one hour after refreshing substrate. With 5 g/L acetate, the maximum voltages were 560 and 460 mV in the i-MFC and controlled MFC (c-MFC), respectively. With 10 g/L acetate, the maximum voltage of the i-MFC was much higher than that of the c-MFC (500 vs. 300 mV). With the acetate concentrations of 5 and 10 g/L, the maximum power densities in the i-MFC were 610 50 and 370 40 mW/m(2), respectively, while the maximum power densities in the c-MFC were 343 30 and 240 20 mW/m(2), respectively. Cyclic voltammetry measurements indicated that microbial activity of the i-MFC anode was higher than that of the c-MFC anode under the high acetate concentration (3.00 vs. 2.19 mA). The relative abundance of Geobacter on the i-MFC anode was much higher than that on the c-MFC anode (62% vs. 40%). The in immobilization strategy provided an easily performed and efficient way to keep the activity of exoelectrogens, resulting in the improvement of MFC performance. (C) 2016 Elsevier Ltd. All rights reserved.