TG–FTIR and Py–GC/MS analysis on pyrolysis and combustion of pine sawdust

Pyrolysis and combustion of pine sawdust have been investigated by using thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG–FTIR) analysis in this paper. Pyrolysis–gas chromatography and mass spectrometry (Py–GC/MS) analysis was employed to characterize subsequently the structure and composition of evolving gas in pine sawdust pyrolysis process. TG results showed that both pyrolysis and combustion of pine sawdust presented three weight loss stages, respectively. The apparent activation energy of pyrolysis reaction is 108.18kJmol^‑1 in temperature of 239–394°C, while under combustion process which is 128.43kJmol^‑1 and 98.338kJmol^‑1 in 226–329°C and 349–486°C, respectively. The evolving gaseous products during the pyrolysis and combustion infrared spectrums such as H₂O, CH₄, CO, CO₂, phenol and alkane were found. Py–GC/MS results indicated that the main compounds of pine sawdust thermal decomposition were small molar gases, acetaldehyde, acetic acid, anhydride with formic and acetic anhydride. And possible formation pathways for main pyrolysis products were tentatively presented.