title: The effect of ethanol on hydroxyl and carbonyl groups in biopolyol produced by hydrothermal liquefaction of loblolly pine: (31)P-NMR and (19)F-NMR analysis.
abstract: The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390°C for 30min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300°C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1wt.% bio-oil and 2.4wt.% solid residue. (31)P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by (19)F-NMR, which showed that ethanol reduced the concentration of carbonyl groups.
authors.affiliation: School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849 USA.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Celikbag
authors.affiliation: School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849 USA; Center for Bioenergy and Bioproducts, Auburn University, Auburn, AL 36849 USA; Department of Biosystem Engineering, Auburn University, Auburn, AL 36849, USA. Electronic address: bkv0003@auburn.edu.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Via
authors.affiliation: Center for Bioenergy and Bioproducts, Auburn University, Auburn, AL 36849 USA; Department of Biosystem Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Sushil
authors.initials: S
authors.lastname: Adhikari
authors.affiliation: Department of Biosystem Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Gisela
authors.initials: G
authors.lastname: Buschle-Diller
authors.affiliation: Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Auad
mesh_terms: D001704:Biopolymers / Q000302:isolation & purification*; D000431:Ethanol / Q000737:chemistry*; D017665:Hydroxyl Radical; D041603:Pinus taeda / Q000737:chemistry*; D011108:Polymers / Q000032:analysis; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D001704:Biopolymers; D011108:Polymers; D012996:Solutions; D012997:Solvents; C024617:polyol; D014867:Water; D017665:Hydroxyl Radical; D000431:Ethanol
keywords: (19)F-NMR; (31)P-NMR; Bio-oil; Biopolyol; Hydrothermal liquefaction