title: Application of microbial electrolysis cells to treat spent yeast from an alcoholic fermentation.
abstract: Spent yeast (SY), a major challenge for the brewing industry, was treated using a microbial electrolysis cell to recover energy. Concentrations of SY from bench alcoholic fermentation and ethanol were tested, ranging from 750 to 1500mgCOD/L and 0 to 2400mgCOD/L respectively. COD removal efficiency (RE), coulombic efficiency (CE), coulombic recovery (CR), hydrogen production and current density were evaluated. The best treatment condition was 750mgCOD/LSY+1200mgCOD/L ethanol giving higher COD RE, CE, CR (90±1%, 90±2% and 81±1% respectively), as compared with 1500mgCOD/LSY (76±2%, 63±7% and 48±4% respectively); ethanol addition was significantly favorable (p value=0.011), possibly due to electron availability and SY autolysis. 1500mgCOD/LSY+1200mgCOD/L ethanol achieved higher current density (222.0±31.3A/m(3)) and hydrogen production (2.18±0.66 [Formula: see text] ) but with lower efficiencies (87±2% COD RE, 71.0±.4% CE). Future work should focus on electron sinks, acclimation and optimizing SY breakdown.
authors.affiliation: Tecnologico de Monterrey, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L., CP 64849, Mexico.
authors.forename: Ornella
authors.initials: O
authors.lastname: Sosa-Hernández
authors.affiliation: Biodesign Institute, Swette Center for Environmental Biotechnology, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85287, USA.
authors.forename: Sudeep C
authors.initials: SC
authors.lastname: Popat
authors.affiliation: Biodesign Institute, Swette Center for Environmental Biotechnology, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85287, USA.
authors.forename: Prathap
authors.initials: P
authors.lastname: Parameswaran
authors.affiliation: Tecnologico de Monterrey, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L., CP 64849, Mexico.
authors.forename: Gibrán Sidney
authors.initials: GS
authors.lastname: Alemán-Nava
authors.affiliation: School for Engineering of Matter, Transport and Energy, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85287, USA.
authors.forename: César I
authors.initials: CI
authors.lastname: Torres
authors.affiliation: Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro, Qro 76230, Mexico.
authors.forename: Germán
authors.initials: G
authors.lastname: Buitrón
authors.affiliation: Tecnologico de Monterrey, Campus Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey, N.L., CP 64849, Mexico. Electronic address: r.parra@itesm.mx.
authors.forename: Roberto
authors.initials: R
authors.lastname: Parra-Saldívar
mesh_terms: D001329:Autolysis; D001419:Bacteria / Q000378:metabolism; D057919:Biological Oxygen Demand Analysis; D004572:Electrolysis; D004583:Electrons; D004867:Equipment Design; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D006859:Hydrogen / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D013696:Temperature; D015003:Yeasts
chemical_list: D000431:Ethanol; D006859:Hydrogen
keywords: COD removal; Coulombic efficiency; Hydrogen; Microbial electrolysis cell; Spent yeast