The effect of the sulfiding mixture (H-2/H2S and N-2/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 degrees C and 5 MPa. Reaction rates for both catalysts increased upon sulfiding in N-2/H2S mixture. This N-2/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. (C) 2010 Elsevier BM. All rights reserved.