title: Gas-Phase Reactions of Glyceraldehyde and 1,3-Dihydroxyacetone as Models for Levoglucosan Conversion during Biomass Gasification.
abstract: Levoglucosan, the major intermediate in wood gasification, is decomposed selectively to C1/C2 fragments at 550-600 °C. Kinetic analyses suggest that radical chain mechanisms with the involvement of short-lived carbonyl intermediates explain the lower production of larger fragments. To address this hypothesis, the gas-phase reactivities of glyceraldehyde (Gald), 1,3-dihydroxyacetone (DHA), and glycerol, as simple C3 model compounds, were compared at 400-800 °C under N2 flow at residence times of 0.9-1.4 s. Retro-aldol fragmentation and dehydration proceeded for the pyrolysis of Gald/DHA at 400 °C, far below the 600 °C decomposition point of glycerol. Pyrolysis of Gald/DHA generated exclusively syngas (CO and H2). On the basis of the results of theoretical calculations, the effects of carbonyl intermediates on reactivity were explained by postulating uni- and bimolecular reactions, although the bimolecular reactions became less effective at elevated temperatures.
authors.affiliation: Graduate school of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto, 606-8501, Japan.
authors.forename: Asuka
authors.initials: A
authors.lastname: Fukutome
authors.affiliation: Graduate school of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto, 606-8501, Japan. kawamoto@energy.kyoto-u.ac.jp.
authors.forename: Haruo
authors.initials: H
authors.lastname: Kawamoto
authors.affiliation: Graduate school of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto, 606-8501, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Saka
mesh_terms: D018533:Biomass; D004098:Dihydroxyacetone / Q000737:chemistry*; D005740:Gases / Q000737:chemistry*; D005947:Glucose / Q000031:analogs & derivatives* / Q000737:chemistry; D005985:Glyceraldehyde / Q000737:chemistry*; D008962:Models, Theoretical
chemical_list: D005740:Gases; D005985:Glyceraldehyde; C014989:1,6-anhydro-beta-glucopyranose; D005947:Glucose; D004098:Dihydroxyacetone
keywords: biomass; carbohydrates; density functional calculations; gas-phase reactions; pyrolysis