Synthesis, characterization and catalytic activity of highly dispersed Mo-SBA-15

Molybdenum-containing SBA-15 materials have been prepared using a co-condensation method with a wide range of metal loadings under acidic conditions and using non-ionic surfactants. These materials display good catalytic activity in the epoxidation of olefins with alkyl hydroperoxides, being the catalytic activity correlated with the nature of supported molybdenum species. The immobilized metal species show different stabilities against leaching depending on their nature. Reutilization catalytic tests indicate that some fraction of the molybdenum show a high stability and it seems to be responsible for the major part of the catalytic activity of these materials. Stable molybdenum species use in a very efficient manner the alkyl hydroperoxide in the epoxidation of olefins whereas leached species lead to non-oxidative consumption of the oxidant and promote secondary reactions.

Mo-containing SBA-15 materials with high accessibility of metallic sites have been prepared under high acidic conditions using non-ionic surfactants. Microenvironment of Mo species within the silica support influences dramatically on the oxidant efficiency and stability of active sites in the liquid-phase epoxidation of 1-octene using tert-butyl hydroperoxide as oxidant. Figure optionsDownload as PowerPoint slide