Production of Bio-Based Chemicals, Acetic Acid and Furfural, through Low-Acid Hydrothermal Fractionation of Pine Wood (Pinus densiflora) and Combustion Characteristics of the Residual Solid Fuel

Low-acid hydrothermal (LAH) fractionation conditions were optimized for the effective degradation of hemicellulose from pine wood (Pinus densiflora). The hemicellulosic sugar yield was maximized at 82.5% when fractionated 190 °C, with 0.5 wt.% sulfuric acid, and 10 min. Consecutively, acidified heat treatment zinc chloride solvent extraction ethyl acetate carried out recovery bio-based platform chemicals, such as furfural acetic liquid hydrolysate through liquid–liquid (LLE). Overall, 61.5% xylose decomposed into furfural, acid 62.3% 66.1%. After LAH fractionation, 64.8% solid remained pelletized. pellets showed excellent fuel characteristics, i.e., significant ash rejection (74.5%) high calorific values (4770 kcal/kg), precursors NOx SOx also decreased by up to 60.0% 71.4%, respectively.