Selective formation of levoglucosenone and 1,4:3,6-dianhydro-α-D-glucopyranose

For the first time, the non-catalytic formation of value-added liquid products, such as levoglucosenone (LGO) and 1,4:3,6-dianhydro-α-D-glucopyranose (DGP) from wood cellulose pulp residue (WCPR) has been achieved using dry torrefaction (DT) under solvent-free conditions and in a nitrogen atmosphere. This study systematically examined the influence of reaction conditions on the DT process, evaluating their effects on the surface morphology and elemental composition of the resulting biochar. This process encompassed a temperature range of 210–300 °C and reaction durations spanning from 15 to 60 min. Optimal conditions for liquid product selectivity were identified, achieving 67.7 % selectivity for LGO at 270 °C after 15 min and 32.6 % selectivity for DGP at 240 °C after 30 min. The highest yields were obtained at 300 °C after 60 min, reaching 10.5 % for LGO and 8.5 % for DGP.