Characterization and carbonylic hydrogenation of methyl oleate over Ru-Sn/Al2O3: Effects of metal precursor and chlorine removal

Hydrogenation of methyl oleate to oleyl alcohol was evaluated over Ru-Sn/Al2O3 catalysts, prepared from different precursors, at 270 degrees C and 5.0 MPa. Two kinds of metal precursors were employed: chlorine-free precursors and inorganic chlorides. in addition, several methods for chlorine removal of metal-chloride-based catalysts were studied. Catalysts were characterized by EDX, XRF, DRX, BET and TPR analyses. Selectivity toward unsaturated alcohol was higher with the bimetallic catalyst based on chlorine-free precursors than with the catalyst based on metal chlorides, owing that chlorine avoids, at certain extent, an effective interaction between ruthenium and tin species. However, the most selective catalyst was the bimetallic one based on chloride precursors and reduced with NaBH4, due to elimination of residual chlorine and higher dispersion of Ru-Sn species. (C) 2009 Elsevier B.V. All rights reserved.