In Situ Formation of CoMoS Interfaces for Selective Hydrodeoxygenation of p-Cresol to Toluene

Abstract

Catalytic hydrodeoxygenation (HDO) of phenolics to aromatics is one of the most important reaction routes in bio-oil upgrading. Sulfided CoMo catalysts are good candidates for this reaction, but their activities are strongly associated with the number of exposed surface sites and Co–Mo synergy. Herein, we employ zeolitic imidazolate framework-67 as a cobalt precursor and template for inverse deposition of MoS2 ultrathin sheets inside the framework to form CoMoS interfaces by using a simple hydrothermal method. The size-confined MoS2 possesses a few-layered structure and abundant surface defects. It is found that in situ generation of a CoMoS active phase would take place to reach the best activity of our catalysts under the HDO reaction condition or by H2 prereduction treatment. With varying different Co–Mo molar ratios, the optimized CoMoS-0.18 catalyst exhibits the highest HDO activity, with a p-cresol conversion of 92.4% and a toluene selectivity of 95.5% at 250 °C. The high performance is ascribed to the formation of an accessible surface CoMoS phase after surface restructuring.