Synergy of metallic Pt and oxygen vacancy sites in Pt–WO3−x catalysts for efficiently promoting vanillin hydrodeoxygenation to methylcyclohexane

Abstract

Pt–WO_3−x catalysts showed very high catalytic activity in complete hydrodeoxygenation (HDO) of vanillin, a typical model compound of lignin, affording methylcyclohexane (MCH) in 92.5% yield at 220 °C, under 4.0 MPa H₂ and in 2 h in n-hexane as the solvent. By tuning the reduction time and pre-treatment of the WO₃ support, the influence of Pt species and oxygen vacancy sites of Pt–WO_3−x on vanillin HDO performance was analyzed. The reaction pathway of vanillin HDO over Pt–WO_3−x was proposed. Moreover, Pt–WO_3−x showed wide applicability to the HDO of other phenols and high catalytic stability.