Pyrolysis of poplar wood sawdust by TG-FTIR and Py–GC/MS

Pyrolysis of certain poplar wood sawdust (PWS) was studied by thermogravimetric analyzer coupled with Fourier transform infrared spectroscopy (TG-FTIR). Different heating rates were applied with final temperature of 950 °C and about 80% loss weight was observed at the heating rate of 20–80 °C/min. The temperature trend of evolving gaseous products of PWS was also investigated. Following experimental research on pyrolysis of PWS was carried out on a pyrolysis–gas-chromatography/mass spectrometry (Py–GC/MS). Associated with the analysis results of TG-FTIR and Py–GC/MS for the pyrolytic products, PWS undergoes in three consecutive stages, corresponding to (1) moisture evaporation, (2) thermal decomposition, and (3) further carbonization. The main pyrolysis sections and the maximum weight loss rates are similar for different heating rates. Carbonyls, including aldehydes and ketones, are the main volatile products, in addition to phenols, furans, benzenes, acids, and so on. As the main gaseous products, CO, CO2, CH4 are released out greatly. Furthermore, possible pyrolysis mechanisms of cellulose, hemicellulose and lignin in biomass including PWS were also proposed. All of the results and findings would help further understanding of thermal behavior of PWS and its thermo-chemical utilization for fuels and chemicals.