Highly selective demethylation of anisole to phenol over H4Nb2O7 modified MoS2 catalyst

Abstract

Hydrogenolysis of lignin to obtain value-added phenolic chemicals is an important approach for its comprehensive utilization. Herein, H₄Nb₂O₇ modified MoS₂ catalyst with short slabs and narrow stacking degree was successfully synthesized by the one step hydrothermal method and used in the selective demethylation of anisole to phenol. The MoS₂–H₄Nb₂O₇-160 catalyst exhibited the best activity with 97.7% conversion of anisole and 98.0% selectivity of phenol under 3 MPa H₂ pressure at 270 °C for 4 h, which has been rarely reported on anisole transformation over heterogeneous catalysts so far. The characterizations results demonstrated that the H₄Nb₂O₇ modification reduced the slab length and stacking degree of MoS₂ during the hydrothermal process and enhanced the acidity property therefore improved the cleavage ability of C_ArO–CH₃ bond. This study provides a new scheme for the activity enhancement of MoS₂ in lignin demethylation, laying a foundation on the improvement of lignin utilization and the development of renewable energy strategy.