HCl (0.42 mL), formic acid (0.36 mL) and water (0.64 mL). The suspension was then stirred for 5 h at 80 °C and filtered and the residue was washed with dioxane until the solution became clear (solid/cellulose fraction). The combined filtrate was dried at 60 °C under vacuum and extracted with THF followed by drying at 40 °C to obtain a dark oil (liquid/lignin fraction).