Thermodynamic Study on Ligno-Cellulosic Pyrolysis on Wood Materials.

This study aims to examine the thermodynamic-related phenomena that occurred to the liquid smoke and other products (e.g. acetic acid and solid residue) that resulted from the pyrolysis on three kinds of lignin-cellulosic materials (i.e. teak wood, pine wood sawdust). The pyrolysis proceeded at five maximum temperatures, i.e. 110-500°C, each for 5 hours. At 200°C, the liquid smoke yield from those two materials achieved the greatest, i.e. 17.05% (teak wood), and 14.46% (pine wood). Acetic acid concentration as present in the liquid smoke varied, i.e. 5.09-9.78% (from teak wood), and 3.63-5.29% (pine wood). The formation of acetic acid was not spontaneous due to the positive change in Gibbs free energy with increasing pyrolysis temperature. Formation of solid residue from each of the three lignincellulosic materials was accompanied with the positive changes (>0) in both enthalpy and entropy, indicating of its endothermic process. The enthalpy/heat content of the solid residue increased with the pyrolysis temperature, suggesting the carbonization occurred intensively (e.g. increasing the carbon content as well as charcoal portion). The heat content/calorific value of the teak-wood's solid residue was the greatest (18.89-28.36MJ/kg), followed in decreasing order by those from teak wood's residue (18.73-27.92 MJ/kg, as the second highest) Results of these thermodynamicrelated phenomena expectedly bring remarkable benefits, e.g. (1) understanding whether the formation of particular pyrolysis products (e.g. organic acid, acetic acid, and charcoal) was endothermic, not-spontaneous, or something else. [ABSTRACT FROM AUTHOR]