Relevance of Sulfiding Pretreatment on the Performance of Re/Zro2 and Re/Zro2-Sulfated Catalysts for the Hydrodeoxygenation of Guayacol

RUIZ P.; LEIVA, K.; GARCIA, R.; REYES P; FIERRO, J.; ESCALONA, N.
Applied Catalysis A: General 384 (2010) 78–83.

DOI: 10.1016/j.apcata.2010.06.009

Abstract

The effect of the sulfiding mixture (H₂/H₂S and N₂/H₂S) over Re/ZrO₂ and Re/ZrO₂-sulfated catalysts in the hydrodeoxygenation (HDO) of 2-methoxyphenol (guayacol) in the presence of CS₂ has been studied. The catalysts were prepared by wet impregnation and characterized by X-ray diffraction (XRD), BET surface area, X-ray photoelectron spectroscopy (XPS) and surface acidity techniques. The reaction was carried out in a batch reactor at 300 °C and 5 MPa. Reaction rates for both catalysts increased upon sulfiding in N₂/H₂S mixture. This N₂/H₂S mixture promotes the formation of ReS_(2 − x) species over support surfaces and leads to an increase in the rate of direct demethoxylation and an enhancement in the phenol/cathecol ratio. An increase in the concentration of CS₂ leads to an increase in the HDO and cathecol and inhibits the demethoxylation of guayacol.