Volatile compounds formed from the pyrolysis of chitosan

Chitosan is a renewable resource for the production of nitrogen-containing aromatic heterocyclics. It was found that chitosan started to decompose and produce some volatile compounds at around 525 K in a nitrogen atmosphere, the volatiles were characterized by Fourier transform infrared spectrometer. The apparent activation energy for the thermal degradation of chitosan was determined. To further investigate the degradation, chitosan was pyrolyzed under vacuum at 553 K for 1 h, and the volatile compounds were analyzed by gas chromatography/mass spectrometry. The volatile compounds included aromatic heterocyclics such as pyrazines, pyridines, pyrroles and furans, and the pyrazines were the major products. The pyrolysis mechanism of chitosan was also proposed.