Identification of the cleavage mechanisms and hydrogenation activity of the β-O-4 linkage in a lignin model compound over Ni-CeO2/H-ZSM-5

Abstract

Strategies for catalytic lignin depolymerization to yield ethylbenzene chemicals are green, sustainable and environmentally friendly methods. In this study, a series of Ni-CeO2/H-ZSM-5 catalysts were prepared via the precipitation method, which catalytically degraded the β-O-4 chemical bonding structure to yield ethylbenzene chemicals. The 2-(2-methoxy-phenoxy)-1-phenylethanol substance (β-O-4) was selected as a typical lignin model compound for the investigation of the intrinsic depolymerization mechanism and the catalytic performance. The results demonstrated that the introduced CeO2 active phase can effectively promote the catalytic conversion of the β-O-4 chemical bonding structure to ethylbenzene chemicals. Physicochemical data demonstrate that the reaction pathways and hydrogenation selectivity were effectively regulated and controlled by the tuning of the dehydration and hydrogenolysis processes via the introduction of CeO2, which realized the selective adjustment of the redox properties and the surface valence states of active species in the catalytic process due to its excellent oxygen transfer performance.