Hydrogenation of 9‐octadecenoic acid by Ru−Sn−Al 2 O 3 catalysts: Effects of catalyst preparation method

Evaluation of the method of preparation and the sequence of metal incorporation onto the catalyst showed that they had profound effects on the catalytic behavior of Ru−Sn−Al 2 O 3 catalysts used in the selective hydrogenation of oleic acid to 9‐octadecen‐1‐ol. When Ru was loaded first onto the support and then followed by Sn, the catalyst had lower activity but greater ability to preserve the unsaturated bond. On the other hand, when the sequence of loading was reversed, the behavior of the catalyst changed correspondingly, i.e., the catalyst showed higher activity but poorer ability to protect the unsaturated bond. The metal particles incorporated via the sol‐gel method were finely and evenly distributed on the support. As such, they were more readily shielded by the second metal particles that were subsequently incorporated via the impregnation process. When both metals were loaded via the sol‐gel process, the best result was obtained with superior performance in activity, as well as selectivity in the preservation of double bond.