MOLECULAR-BEAM MASS-SPECTROMETRIC ANALYSIS OF LIGNOCELLULOSIC MATERIALS .1. HERBACEOUS BIOMASS

A rapid analytical technique has been developed to qualitatively scree n and quantitatively analyze biomass feedstocks for conversion into hy drocarbon fuels and chemicals. In this rapid analytical pyrolysis appr oach, herbaceous biomass feedstocks stored in the open without cover f or 6 to 9 months were characterized using the molecular-beam mass spec trometer (MBMS). The biomass materials were pyrolyzed at 600 degrees C and the volatile pyrolysis products were analyzed in real time by the MBMS. The mass spectral data were further analyzed by multivariate st atistical techniques (Factor Analysis). The contents of nitrogen compo unds, pentosans and hexosans estimated from the pyrolysis mass-spectro metric/multivariate analysis techniques correlated well with the resul ts obtained by conventional wet chemical methods. However, lignin corr elation was very weak because of the presence of microbial degradation products of biomass (humic material) that interfered with the Klason lignin analysis. This rapid analytical technique was used to analyze v arious fractions of the stored biomass feedstocks. A comparison of exp osed surface biomass materials and the unexposed materials showed that the exposed fraction lost 30% (wt) of the carbohydrate component of t he biomass relative to the fresh material.