Ionic liquid modified montmorillonite-supported Ru nanoparticles: highly efficient heterogeneous catalysts for the hydrodeoxygenation of phenolic compounds to cycloalkanes

The Ru/MMT@IL-SO3H catalyst was prepared by immobilizing Ru nanoparticles onto montmorillonite (MMT) with the assistance of an acidic ionic liquid (1-sulfobutyl-3-methylimidazolium hydrosulfate, IL-SO3H). Transmission electron microscopy examination indicated that the loaded Ru species were distributed uniformly on the MMT support with a particle size of about 1.3 nm, which existed mainly in the form of a metallic state as confirmed by X-ray photoelectron spectroscopy analysis. X-Ray diffraction analysis indicated that the interlayer distance of MMT was increased due to the impregnation of IL-SO3H. The activity of Ru/MMT@IL-SO3H for hydrodeoxygenation (HDO) of various phenolic compounds was investigated. It was demonstrated that the as-prepared catalyst served as a bifunctional catalyst and displayed high efficiency for HDO reactions of a series of phenolic compounds to cycloalkanes.