Herein we report the fast pyrolysis of the lignin monomers sinapyl and coniferyl alcohol, as well as mixtures of the two, at 650 °C using pyrolysis-GC/MS. The total ion chromatogram area % of certain marker pyrolysates for each alcohol were summed and used to calculate sinapyl:guaiacyl (S:G) ratios in the mixtures; these ratios were then plotted against the actual molar S:G ratios of the starting material. 13 coniferyl alcohol marker pyrolysates and 9 sinapyl alcohol marker pyrolysates provided acceptable linear correlation, whereas several other marker groups chosen did not correlate to the actual S:G ratio in the starting material. Results indicated that the demethoxylation of sinapyl alcohol and/or its pyrolysates occurs during pyrolysis at 650 °C; however, the amount of demethoxylated products generated is statistically insignificant. Having obtained the pyrolysis profile of the various S:G mixtures, marker pyrolysates for the calculation of the S:G ratio in lignin can be carefully selected according to unique samples. These marker groups can then be calibrated against known S:G ratios to provide analysis of the actual S:G ratio of lignin in biomass. For example, pyrolysates chosen from the pyrolysis of peach pit lignin were calibrated in order to determine the S:G ratio in peach pit lignin. The resulting S:G ratio was similar to that obtained from capillary electrophoresis of the products from KMnO4 oxidation of the peach pit lignin.
|Number of pages||9|
|Journal||Journal of Analytical and Applied Pyrolysis|
|State||Published - Jan 2013|
Bibliographical noteFunding Information:
This work was funded by a grant from the National Science Foundation ( EFRI-0937657 ) and by the U.S. Department of Energy (DOE) under award no. DE-FG36-O8GO88043. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE.
- Lignin monomers
- S:G ratio
ASJC Scopus subject areas
- Analytical Chemistry
- Fuel Technology