title: Effects of acid and alkali promoters on compressed liquid hot water pretreatment of rice straw.
abstract: In this study, effects of homogeneous acid and alkali promoters on efficiency and selectivity of LHW pretreatment of rice straw were studied. The presences of acid (0.25%v/v H2SO4, HCl, H3PO4, and oxalic acid) and alkali (0.25 w/v NaOH) efficiently promoted hydrolysis of hemicellulose, improved enzymatic digestibility of the solids, and lower the required LHW temperature. Oxalic acid was a superior promoter under the optimal LHW conditions at 160 °C, leading to the highest glucose yield from enzymatic hydrolysis (84.2%) and the lowest formation of furans. Combined with hydrolyzed glucose in the liquid, this resulted in the maximal 91.6% glucose recovery from the native rice straw. This was related to changes in surface area and crystallinity of pretreated biomass. The results showed efficiency of external promoters on increasing sugar recovery and saving energy in LHW pretreatment.
authors.affiliation: The Joint Graduate School for Energy and Environment (JGSEE), King Mongkut's University of Technology Thonburi, Prachauthit Road, Bangmod, Bangkok 10140, Thailand.
authors.forename: Saksit
authors.initials: S
authors.lastname: Imman
authors.affiliation: Enzyme Technology Laboratory, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand.
authors.forename: Jantima
authors.initials: J
authors.lastname: Arnthong
authors.affiliation: PTT Research and Technology Institute, Phahonyothin Road KM. 78, Wang Noi, Phra Nakhon Si Ayutthaya 13170, Thailand.
authors.forename: Vorakan
authors.initials: V
authors.lastname: Burapatana
authors.affiliation: Enzyme Technology Laboratory, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand. Electronic address: verawat@biotec.or.th.
authors.forename: Verawat
authors.initials: V
authors.lastname: Champreda
authors.affiliation: The Joint Graduate School for Energy and Environment (JGSEE), King Mongkut's University of Technology Thonburi, Prachauthit Road, Bangmod, Bangkok 10140, Thailand.
authors.forename: Navadol
authors.initials: N
authors.lastname: Laosiripojana
mesh_terms: D056804:Biofuels; D006358:Hot Temperature; D006851:Hydrochloric Acid / Q000737:chemistry; D008031:Lignin / Q000737:chemistry*; D012275:Oryza / Q000737:chemistry*; D019815:Oxalic Acid / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry*; D011312:Pressure; D012972:Sodium Hydroxide / Q000737:chemistry*; D013464:Sulfuric Acids / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D056804:Biofuels; D010756:Phosphoric Acids; D013464:Sulfuric Acids; D014867:Water; C036909:lignocellulose; D012972:Sodium Hydroxide; D008031:Lignin; D019815:Oxalic Acid; C030242:phosphoric acid; C033158:sulfuric acid; D006851:Hydrochloric Acid
keywords: Biorefinery; Lignocelluloses; Liquid hot water pretreatment; Promoter; Rice straw