| Catalytic fast pyrolysis of lignin has been proposed for the sustainable production of fuels and aromatic compounds. However, due to its heterogeneous structure, pyrolysis of lignin results in low selectivity and yields. It is therefore imperative to understand the relationship between lignin properties and pyrolytic behavior to produce lignin that is more suitable for pyrolysis. Lignin-rich solids were recovered from hot-water extracts of sugar maple; native and after electron beam irradiation (EBI). Along with milled wood lignins and two technical lignins (kraft softwood and hydrolytic hardwood), these lignins were chemically and thermally characterized and subjected to (catalytic) fast pyrolysis (Py-GCMS; TiO2/zeolite). Results showed that enrichment in syringyl units beneficially impacted lignin volatility but substantially hindered production of non-oxygenated "simple" phenols. EBI did not enhance production of aromatics (phenols/methylated aromatics). Lignins originating from softwoods and hardwoods should be studied for the pyrolytic production of phenolic and methylated aromatics, respectively. |
