Enhanced H2 production from corn stalk by integrating dark fermentation and single chamber microbial electrolysis cells with double anode arrangement

• DOI: 10.1016/j.ijhydene.2014.03.065
• Publication Date: 2014-05-05T12:30:30Z
• Authors: Xiao-Hu Li; Da-Wei Liang; Yan-Xia Bai; Yao-Ting Fan; Hong-Wei Hou
• Keywords: Stalk; Dark fermentation; Fermentative hydrogen production; Microbial electrolysis cell

Abstract The low conversion efficiency of substrate is one of the main bottlenecks in dark fermentation for bio-H 2 production. Herein, an enhanced H 2 yield from corn stalk was achieved by integrating dark fermentation and single chamber microbial electrolysis cells (MECs). In the dark fermentation stage, a H 2 yield of 129.8 mL H 2 /g-corn stalk and an average H 2 production rate of 1.73 m 3 /m 3 d were recorded at 20 g/L of corn stalk and initial pH 7.0. The effluent from dark fermentation was diluted and further employed as feedstock to generate H 2 by MECs. A H 2 yield of 257.3 mL H 2 /g-corn stalk, an HPR of 3.43 ± 0.12 m 3 /m 3 d and an energy efficiency of 166 ± 10% were obtained with the effluent COD of 3995.5 mg/L under 0.8 V applied voltage. During MECs operation stage, about 90 ± 2% of acetate was converted to H 2 and the corresponding COD removal reached 44 ± 2% in MECs. Overall, the H 2 yield can reach 387.1 mL H 2 /g-corn stalk by integrating dark fermentation and MECs, which had nearly tripled as against that of dark fermentation.