Lignin oxidation by MnO2 under the irradiation of blue light

Abstract

Traditionally, conventional heat has been required for a large proportion of the oxidation and degradation process to utilise lignin from biomass. A photocatalysis system which is considered as a novel and green strategy for chemical reactions has been applied and a photo-MnO₂ catalytic lignin oxidation method has been developed. In this study, we investigated a promising photocatalytic heterogeneous system for lignin oxidation. Recyclable MnO₂ which is readily available and blue light which is a hazardless light are used in this system. 1-Phenylethanol was used as a model compound to study the suitable conditions for this system. After optimizing the reaction conditions, organosolv lignin, kraft lignin, and alkali lignin were applied to this system and the successful oxidation of lignins and their further degradation were shown.