Titanium-doped ruthenium catalysts were prepared, characterized, and studied in the vapor-phase selective hydrogenation of crotonaldehyde. The catalysts were prepared by co-impregnation and by the chemical vapor deposition (CVD) method. XPS results indicate that titanium was well dispersed on the support for the catalyst prepared by CVD. Ruthenium dispersion was diminished by titanium addition, and a strong interaction of ruthenium with titanium was deduced from CO adsorption microcalorimetry. Results obtained in the vapor-phase hydrogenation of crotonaldehyde showed that the monometallic Ru catalyst had no selectivity toward crotyl alcohol, whereas the RuTi catalyst prepared by the CVD method gave the highest selectivity. (C) 2008 Elsevier Inc. All rights reserved.