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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 °C) are not advantageous regarding the liquefaction yields and, therefore, temperatures around 160–180 °C would be preferable. The best yield for the bark sample (>80 mesh fraction) was obtained at 180 °C for 60 min (61.6%), while for the branches the best yield was obtained at 160 °C for 60 min (62.2%). Under compromised conditions (180 °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.

In the last decades, numerous large forest fires have been recorded in Portugal. On 15 and 16 October 2017, seven extreme wildfires events (EWEs) took place in the central region of Portugal. Aiming to contribute to the assessment of the smoke impact of these EWEs, this study estimates their atmospheric emissions using a bottom-up approach with high spatial and temporal resolution. To this end, fire data were used, such as ignition location and time, propagation, burned area, and fuel load and emission factors according to forest species. A particular fire -EWE in Lousã with a high fuel load -emitted ~50% of the sum of the emissions of the six other case studies. The spatial distribution of the EWE emissions indicates that fuel load is an important component of emissions estimation. The obtained results were compared with remote sensing data, showing good agreement in terms of total values. During these EWEs, particulate matter and carbon monoxide emissions were higher than Portuguese anthropogenic emissions in 2017. This approach contributes to the state of the art on forest fire emissions, reducing uncertainty and obtaining the best possible and detailed quantification of the temporal and spatial variability of EWE emissions.