The efficient synthesis of a molybdenum carbide catalystvia H2-thermal treatment of a Mo(vi)–hexamethylenetetramine complex

Abstract

An efficient method for preparation of Mo₂C catalyst is described, where Mo₂C is obtained by the heat treatment of a single solid precursor containing (NH₄)₆Mo₇O₂₄ and hexamethylenetetramine (HMT) at 923 K in H₂ flow without conventional prolonged carbonization. The catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area measurement, and transmission electron microscopy (TEM). Furthermore, these catalysts are evaluated in the dibenzothiophene (DBT) hydrodesulfurization (HDS) reaction, and proved to be superior to those prepared by a temperature-programmed reduction (TPRe) method. The better catalytic performance is ascribed to higher dispersion of Mo₂C on the support and a lower surface polymeric carbon content. This hydrogen thermal treatment (HTT) method provided a new strategy for the preparation of a highly active molybdenum carbide catalyst.