Abstract
Carbon materials prepared by biomass pyrolysis have been studied for conversion of lignin into phenols. In this study, the control mechanism of free radicals on phenolic products selectivity was studied using guaiacol as a model chemical. The results showed that gaseous radicals or carbon-centered radicals of carbon materials could promote phenols formation through different mechanisms. In gas-phase system, the selectivity of phenols was mainly controlled by methyl radicals which led to a theoretical selectivity of phenols lower than 50%. In the heterogeneous system, methyl radicals and phenolic radicals were easily and rapidly adsorbed on the carbon edge sites. The o-hydroxyphenoxy radical was the key intermediate and was firstly absorbed on the carbon center radical sites where phenols produced at the same position after undergoing desorption and hydrogenation. In conclusion, the present study concluded that conversion of lignin to phenols can proceed rapidly as long as there are carbon-centered radicals distributed at zigzag edge on the carbon surface.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.