title: Production of hydrogen, ethanol and volatile fatty acids from the seaweed carbohydrate mannitol.
abstract: Fermentative hydrogen from seaweed is a potential biofuel of the future. Mannitol, which is a typical carbohydrate component of seaweed, was used as a substrate for hydrogen fermentation. The theoretical specific hydrogen yield (SHY) of mannitol was calculated as 5 mol H2/mol mannitol (615.4 mL H2/g mannitol) for acetic acid pathway, 3 mol H2/mol mannitol (369.2 mL H2/g mannitol) for butyric acid pathway and 1 mol H2/mol mannitol (123.1 mL H2/g mannitol) for lactic acid and ethanol pathways. An optimal SHY of 1.82 mol H2/mol mannitol (224.2 mL H2/g mannitol) was obtained by heat pre-treated anaerobic digestion sludge under an initial pH of 8.0, NH4Cl concentration of 25 mM, NaCl concentration of 50mM and mannitol concentration of 10 g/L. The overall energy conversion efficiency achieved was 96.1%. The energy was contained in the end products, hydrogen (17.2%), butyric acid (38.3%) and ethanol (34.2%).
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; Science Foundation Ireland (SFI), Marine Renewable Energy Ireland (MaREI) Centre, Ireland; School of Engineering, University College Cork, Cork, Ireland.
authors.forename: Ao
authors.initials: A
authors.lastname: Xia
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; Science Foundation Ireland (SFI), Marine Renewable Energy Ireland (MaREI) Centre, Ireland; School of Engineering, University College Cork, Cork, Ireland.
authors.forename: Amita
authors.initials: A
authors.lastname: Jacob
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; Science Foundation Ireland (SFI), Marine Renewable Energy Ireland (MaREI) Centre, Ireland; School of Engineering, University College Cork, Cork, Ireland.
authors.forename: Christiane
authors.initials: C
authors.lastname: Herrmann
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; Science Foundation Ireland (SFI), Marine Renewable Energy Ireland (MaREI) Centre, Ireland; School of Engineering, University College Cork, Cork, Ireland.
authors.forename: Muhammad Rizwan
authors.initials: MR
authors.lastname: Tabassum
authors.affiliation: Environmental Research Institute, University College Cork, Cork, Ireland; Science Foundation Ireland (SFI), Marine Renewable Energy Ireland (MaREI) Centre, Ireland; School of Engineering, University College Cork, Cork, Ireland. Electronic address: jerry.murphy@ucc.ie.
authors.forename: Jerry D
authors.initials: JD
authors.lastname: Murphy
mesh_terms: D000641:Ammonia / Q000032:analysis; D056804:Biofuels / Q000032:analysis; D000431:Ethanol / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005285:Fermentation / Q000187:drug effects; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008353:Mannitol / Q000378:metabolism* / Q000494:pharmacology; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D009584:Nitrogen / Q000032:analysis; D012624:Seaweed / Q000737:chemistry*; D012964:Sodium / Q000494:pharmacology; D012995:Solubility; D014865:Waste Disposal, Fluid
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D000431:Ethanol; D008353:Mannitol; D000641:Ammonia; D006859:Hydrogen; D012964:Sodium; D009584:Nitrogen
keywords: Biofuels; Ethanol; Hydrogen; Mannitol; Seaweed