abstract
Eucalyptus globulus forest residues, bark, and branches, were characterized by wet chemistry methods and involved in the liquefaction process using a glycerol-ethylene glycol reaction mixture (1:1, v/v) catalyzed by strong mineral acid (3% H2SO4) or strong mineral base (6% KOH). The effect of the reaction conditions (temperature and duration) and the particle size on the yield of liquefied products have been evaluated. Acid catalysis revealed remarkably higher yields (25-50%) than when using basic catalyst. It was considered that bark was more vulnerable to liquefaction with respect to particle size than branches. Too high temperatures (>180 degrees C) are not advantageous regarding the liquefaction yields and, therefore, temperatures around 160-180 degrees C would be preferable. The best yield for the bark sample (>80 mesh fraction) was obtained at 180 degrees C for 60 min (61.6%), while for the branches the best yield was obtained at 160 degrees C for 60 min (62.2%). Under compromised conditions (180 degrees C for 60 min), the fine fraction (>80 mesh) of bark and branches did not show significant differences between their liquefaction yields and can be processed together while adjusting the suitable processing time. The main advantage of the use of these residues instead of solid wood is that it would bring the Forest managing companies a much higher income for their wastes that are usually burned and the use of lignocellulosic materials in detriment of petroleum-based materials for the production of polymers would make industry less dependent on oil prices fluctuations.
keywords
SUPERCRITICAL-FLUID EXTRACTION; GLYCEROL-BASED LIQUEFACTION; LIPOPHILIC EXTRACTIVES; CHEMICAL-COMPOSITION; POLYHYDRIC ALCOHOLS; POLYURETHANE FOAMS; RAPID LIQUEFACTION; CORK LIQUEFACTION; WOOD-LIQUEFACTION; BIOPOLYOLS
subject category
Chemistry; Engineering; Materials Science; Physics
authors
Fernandes, A; Cruz-Lopes, L; Dulyanska, Y; Domingos, I; Ferreira, J; Evtuguin, D; Esteves, B
our authors
Dmitry Evtyugin
Associate Professor with Aggregationacknowledgements
This research was funded by national funds through FCT-FundacAo para a Ciencia e Tecnologia, I.P., through CERNAS Research Centre, within the scope of the project UIDB/00681/2020.