title: Two-stage conversion of crude glycerol to energy using dark fermentation linked with microbial fuel cell or microbial electrolysis cell.
abstract: Crude glycerol is a main byproduct of the biodiesel industry, and the beneficial use of waste glycerol has been a major challenge. This study characterises the conversion of crude glycerol into bioenergy such as H2 and electricity using a two-stage process linking dark fermentation with a microbial fuel cell (MFC) or microbial electrolysis cell (MEC). The results showed that fermentation achieved a maximum H2 rate of 332 mL/L and a yield of 0.55 mol H2/mol glycerol, accompanied by 20% of organic removal. Fed with the raw fermentation products with an initial COD of 7610 mg/L, a two-chamber MFC produced 92 mW/m(2) in power density and removed 50% of COD. The Columbic efficiency was 14%. When fed with 50% diluted fermentation product, a similar power output (90m W/m(2)) and COD removal (49%) were obtained, but the CE doubled to 27%. Similar substrates were used to produce H2 in two-chamber MECs, and the diluted influent had a higher performance, with the highest yield at 106 mL H2/g COD and a CE of 24%. These results demonstrate that dark fermentation linked with MFC/MEC can be a feasible option for conversion of waste glycerol into bioenergy.
authors.affiliation: Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Songkhla 90112, Thailand.
authors.forename: Teera
authors.initials: T
authors.lastname: Chookaew
authors.affiliation: Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Songkhla 90112, Thailand; Palm Oil Products and Technology Research Center (POPTEC), Faculty of Agro-Industry, Prince of Songkla University, Songkhla 90112, Thailand.
authors.forename: Poonsuk
authors.initials: P
authors.lastname: Prasertsan
authors.affiliation: Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO 80309, USA. Electronic address: zhiyong.ren@colorado.edu.
authors.forename: Zhiyong Jason
authors.initials: ZJ
authors.lastname: Ren
mesh_terms: D001674:Bioelectric Energy Sources; D004572:Electrolysis; D005990:Glycerol / Q000737:chemistry / Q000378:metabolism*; D006859:Hydrogen / Q000737:chemistry / Q000378:metabolism
chemical_list: D006859:Hydrogen; D005990:Glycerol