Assessing the influence of biomass origin and fractionation methods on pyrolysis of primary biomass fractions

Abstract

Pyrolysis has emerged as a highly promising technology for the efficient utilization of organic materials, particularly lignocellulosic materials. This study investigates the behavior and influence of three primary biomass fractions (cellulose, hemicellulose, and lignin) derived from different sources (trees, shrubs, and agricultural residues) on the kinetic of the pyrolysis process. With this objective, different fragmentation methods were employed to isolate the main components of the lignocellulosic biomass, followed by thermogravimetric analysis to examine the pyrolysis process. The activation energy was determined using both, the Friedman differential kinetic models of and the Flynn-Wall-Ozawa integrated method, with the latter being found to be more efficient. The activation energy (Ea) was found to be influenced by several factors, including the fractionation process and the origin of the raw material. For hemicellulose, the Ea was in the range of 200–300 kJ mol, while cellulose showed Ea values of about 180–220 kJ mol-1. In contrast, lignin displayed a wider range of Ea variation, with its vaues being more sensitive to the fractionation method used. Gas samples were collected through adsorption tubes during pyrolysis for analysis of gas stream compositions from different lignocellulosic fractions using gas chromatography/mass spectrometry. Furfural, among other compounds, was predominantly detected in the pyrolysis of hemicellulose fractions, ranging from 6.6 % to 19.3 %.