Thermal treatment of lignin, cellulose and hemicellulose in nitrogen and carbon dioxide

Fast pyrolysis of Lignin produces "Light tar" (soluble in acetone) and "Heavy tar" (soluble in NMP), char, a minor fraction of soot. The "Light tar" contains Vanillin, which can be considered the main primary depolymerization product, but also aliphatics and PAHs. Higher temperature enhances "Heavy tar" and graphitization of the char.

The paper explores the primary products from fast pyrolysis of biomass components: Lignin, Cellulose and Hemicellulose (Xylan). A heated strip reactor is employed at temperatures of 1573 K and 2073 K with N-2 and CO2 atmospheres. Volatiles quench immediately after volatilization on a cold pyrex bridge, while char remains on the heated strip for 3 s. Tar, soot and char are collected and subject to chemical treatments and analyses, including gas chromatography-mass spectrometry and Size Exclusion Chromatography, Thermogravimetric analysis, Raman spectroscopy and Scanning Electron Microscopy.