Five titanium-containing silicates, with different structural features, were compared: TiMCM-41, ordered titanium-grafted mesoporous silica, TiSiO2 Davison, nonordered titanium-grafted porous silica, TiSiO2 Aerosil, nonporous pyrogenic titanium-grafted silica, MST, nonordered in-framework mesoporous material, and TiO2SiO2 Grace, commercial amorphous porous mixed oxide. They were tested in the liquid-phase epoxidation reaction on six unsaturated cyclic terpenes. Good performances were obtained on the commercial mixed oxide and also on the three grafted silicates. The in-framework MST showed the worst activity results. Under these conditions, the porosity features do not affect the catalytic performances noticeably and the use of an ordered mesoporous material is not strictly required. Likewise, a very high surface area is not mandatory in order to have an efficient titanium-grafted catalyst in the epoxidation of these substrates.
Epoxidation on titanium-containing silicates: do structural features really affect the catalytic performance?
Matteo Guidotti;Nicoletta Ravasio;Rinaldo Psaro;Giovanni Ferraris;
2003
Abstract
Five titanium-containing silicates, with different structural features, were compared: TiMCM-41, ordered titanium-grafted mesoporous silica, TiSiO2 Davison, nonordered titanium-grafted porous silica, TiSiO2 Aerosil, nonporous pyrogenic titanium-grafted silica, MST, nonordered in-framework mesoporous material, and TiO2SiO2 Grace, commercial amorphous porous mixed oxide. They were tested in the liquid-phase epoxidation reaction on six unsaturated cyclic terpenes. Good performances were obtained on the commercial mixed oxide and also on the three grafted silicates. The in-framework MST showed the worst activity results. Under these conditions, the porosity features do not affect the catalytic performances noticeably and the use of an ordered mesoporous material is not strictly required. Likewise, a very high surface area is not mandatory in order to have an efficient titanium-grafted catalyst in the epoxidation of these substrates.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
