Thermal decomposition of hemicelluloses
2014 (English)In: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 110, 130-137 p.Article in journal (Refereed) Published
Decomposition modeling of biomass often uses commercially available xylan as model compound representing hemicelluloses, not taking in account the heterogeneous nature of that group of carbohydrates. In this study, the thermal decomposition behavior of seven different hemicelluloses (beta-glucan, arabinogalactan, arabinoxylan, galactomannan, glucomannan, xyloglucan, and xylan) were investigated in inert atmosphere using (i) thermogravimetric analysis coupled to Fourier transform infrared spectroscopy, (ii) differential scanning calorimetry, and (iii) pyrolysis-gas chromatography/mass spectroscopy. Results on decomposition characteristics (mass loss rate, reaction heat and evolving gas composition) were compared and summarized for the different hemicelluloses and for comparison also crystalline cellulose was included in the study. The mass loss rate characteristics differed between the polysaccharides, with cellulose and glucan-based hemicelluloses as the thermally most stable and xylan as the least stable sample. The heat flow during slow heating in nitrogen flow showed a much more exothermal decomposition of xylan compared with the other hemicelluloses. The composition of off-gases during heating showed large differences between the samples. During decomposition of xylan high levels of CO2 and lower levels of other components were formed, whereas also CO, methanol, methane, furfural, 5-hydroxymethylfurfural and anhydrosugars were formed in substantial amounts from the other polysaccharides. The formation of anhydrosugar was correlated to the monosaccharide composition of the polysaccharide chain. The results from the current study contribute to new knowledge concerning thermochemical behavior of different hemicelluloses.
Place, publisher, year, edition, pages
2014. Vol. 110, 130-137 p.
Pyrolysis, Thermal decomposition, Hemicellulose, Xylan
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:umu:diva-100161DOI: 10.1016/j.jaap.2014.08.013ISI: 000347496800015OAI: oai:DiVA.org:umu-100161DiVA: diva2:790600