Abstract

The liquefaction of biomass in ethanol, at the critical point, has high potential due to low temperature and pressure (243 degrees C, 63 bar) when compared with water (374 degrees C, 220 bar). The current study deals with the fractionation of birch wood powder which was liquefied under supercritical ethanol over acidic or non-acidic catalysts, 5 wt % Fe-Beta-H-150 and 5 wt % Fe-SiO2, respectively. Based on the results, the reaction mechanism for the formation of lignin degradation products was proposed. The main phenolic product was isoeugenol over 5 wt % Fe-Beta-H-150 while intermediate products, i.e. such as coniferyl, and sinapyl alcohol, 4-propenyl syringol, syringaresinol, as well as syringyldehyde reacted rapidly further. The thermodynamic analysis was performed by Joback approach and using Gibbs-Helmholtz equation supporting the obtained results. (C) 2020 Energy Institute. Published by Elsevier Ltd. All rights reserved.

Keywords

Hydrothermal liquefaction (HTL); Birch; Supercritical ethanol; Hydrogen atmosphere; Iron supported zeolite; Isoeugenol; Thermodynamic analysis

Published in

Journal of the Energy Institute
2020, volume: 93, number: 5, pages: 2055-2062
Publisher: ELSEVIER SCI LTD

Authors' information