A NEW METHOD TO DETERMINE THE COMPOSITION OF BIOMASS BY THERMOGRAVIMETRIC ANALYSIS

A method for the direct determination of the cellulose and lignin cont ent of biomass has been developed. The method assumes that negligible interactions exist between biomass macrocomponents and it is based on the analysis of thermogravimetric (TG) pyrolysis data. The TG-weighed sum method seems to be reliable and less time consuming than conventio nal methods for the determination of the cellulose and lignin content. Some limitations of the macrocomponent approach in the description of biomass pyrolysis are also discussed. In particular, hemicellulose py rolysis data are analyzed. The use of xylans as substitute materials f or hemicellulose have been critically examined. The results obtained p oint out that the widely practiced use of xylans as substitute compoun ds for the simplified description of hemicellulose pyrolysis can lead to significant errors.