Thermal behavior of extracted and delignified pine wood flour

• Thermal behavior of extracted and delignified pine wood flour was investigated.
• The thermal stability increased with the removal of extractives.
• Polar extractives contribution was greater than the less polar ones.
• The thermal stability decreased with the removal of lignin.

To investigate the effect of extractives and lignin on the thermal stability of wood flour (WF), thermogravimetric analysis was used to determine thermal degradation behavior of extracted and delignified mixed pine WF. The contribution of lignin to thermal stability was greater than that of extractives. Removing extractives resulted in improved thermal stability by increasing onset temperature T0, and solvents with greater polarity contributed more to increasing T0. However, solvent extraction had less effect on decomposition temperature (T2) than did delignification, which significantly decreased T2. A shoulder peak was observed only in delignified WF. Acetone/water extraction, hot-water extraction, and delignification are all significant model terms for variation in T0; delignification is the most significant factor affecting T0 and T2.