Mechanism study of tobacco pyrolysis based on the analysis of characteristic products and in-situ identification of functional groups evolution on pyrolytic char

Abstract

To master the fundamental knowledge of the tobacco thermal degradation process is of great significance for the utilization of tobacco waste. Thermogravimetric analysis coupled with Fourier transform infrared spectrometer was used to analyze the thermal degradation of tobacco lamina and the release behavior of small molecular gas products. Based on the composition and component characteristics of tobacco lamina, the process was divided into four stages to elucidate its thermal degradation mechanism. Tobacco lamina pyrolysis at 200–800 °C was carried out on a microreactor with the products analyzed by gas chromatography-mass spectrometry. On the basis of obtaining variation rule of products belonging to different families of organic compounds with temperature, the evolution properties of products within the same family were summarized. Thereinto, the compositions of nitrogen-containing heterocyclic compounds and hydrocarbons were most affected by temperature. The in-situ infrared of the solid residue during tobacco lamina pyrolysis and the corresponding two-dimensional perturbation correlation infrared spectroscopy were performed to reveal the evolution of functional groups on the surface of the pyrolytic char. The results showed that the dehydration and ring-opening reaction of polysaccharides were earlier than the decomposition of carbonyl containing compounds.