The vapor phase conversion of guaiacol over Ru catalysts supported on C, SiO2, Al2O3, and TiO2 at 400 A degrees C in flowing atmospheric hydrogen is reported. Results indicate a strong synergy between Ru and TiO2 when compared with other catalysts studied as evidenced by enhanced activity for deoxygenation, transalkylation, and decreased deactivation rates. These results are attributed to the enhanced activity of the support brought about by the ability of Ru to reduce TiO2 and create highly active sites for the conversion of guaiacol.