Carbon xerogel supported noble metal catalysts for fine chemical applications

• Author(s): Machado, Bruno ; Gomes, Helder ; Serp, Philippe ; Kalck, Philippe ; Figueiredo, José ; Faria, Joaquim
• Date: 2008
• Persistent ID: http://hdl.handle.net/10198/1324
• Origin: Biblioteca Digital do IPB
• Subject(s): Carbon xerogel; Surface chemistry; Selective hydrogenation; Cinnamaldehyde
• Document Type: Article
• Language: English

Description

Carbon xerogel, a mesoporous material, was produced by polycondensation of resorcinol and formaldehyde. A concentrated nitric acid solution was subsequently used to introduce high amounts of oxygenated groups on the surface. The carbon xerogel served as a support for Pt, Ir and Ru monometallic catalysts by using organometallic precursors. The catalysts were tested in the liquid-phase selective hydrogenation of cinnamaldehyde to cinnamyl alcohol. The introduction of surface groups was important to increase metal dispersion but proved to limit selectivity towards the unsaturated alcohol. After a thermal treatment at 973 K the catalysts showed excellent thermal stability and a narrow metal size distribution. Regarding the catalytic results measured at 50% conversion, Pt catalysts exhibited the highest selectivity to cinnamyl alcohol (73 %) followed by Ir with 65 % and finally Ru with only 32 %.