Effect of Fe/Ir ratio on the surface and catalytic properties in citral hydrogenation on Fe-Ir/TiO2 catalysts

✍ Scribed by P. Reyes; H. Rojas; J.L.G. Fierro

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 212 KB
• Volume: 203
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(03)00263-2

✦ Synopsis

The selective hydrogenation in liquid phase of citral on Ir/TiO 2 and Fe-Ir/TiO 2 catalysts have been studied at 363 K and 8.27 bar. The influence of the reduction temperature and the Fe/Ir atomic ratio on the surface and catalytic properties were investigated. The Fe-Ir/TiO 2 catalysts were prepared by impregnating a FeCl 3 solution on the pre-reduced Ir/TiO 2 monometallic catalyst. In the series of catalysts reduced at low temperatures (473 K), incorporation of iron led to an increase in the activity, reaching a maximum in conversion for an atomic ratio Fe/Ir of 1 and then decreasing for higher Fe-loading. On the contrary, those catalysts reduced at high temperatures (773 K) exhibited a different trend, the catalytic activity decreased continuously upon the incorporation of iron. The results also showed that all the studied Ir/TiO 2 and Fe-Ir/TiO 2 catalysts display high selectivities towards the unsaturated alcohols during citral hydrogenation. The modification of those iridium sites in the close vicinity of Fe 3+ ions is suggested as to explain the observed behavior.