Aerobic epoxidation of olefins catalyzed by Co-SiO₂ nanocomposites

Abstract

Cobalt-silica nanocomposite catalysts have been prepared using sol-gel process followed by drying under different conditions. The use of amino functionalized silane in the gelation step provided homogeneous distribution of the cobalt through the whole material. TEM, XPS and H₂-TPR data reveal that highly dispersed cobalt(II) sites are present in the samples. The catalysts were evaluated for selective aerobic epoxidation of olefins without the use of sacrificial reductant. Among the Co-SiO₂ nanocomposite catalysts, aerogel prepared catalyst has shown superior activity due to the high porosity clubbed with highly accessible cobalt(II) sites.