Catalysis Letters, Vol.85, No.3-4, 223-228, 2003
Vapor-phase epoxidation of propene over Au/Ti-MCM-41 catalysts: influence of Ti content and Au content
Ti-MCM-41 samples were used for propene epoxidation using H-2 and O-2 after Au deposition by deposition precipitation. Au nanoparticles supported on Ti-MCM-41 with Ti incorporated hydrothermally followed by post-synthesis grafting gave higher propene oxide yields than Ti-MCM-41 with Ti incorporated hydrothermally or by grafting. Au L-3-edge EXAFS spectra show he presence of metallic Au for the low Au content (0.21 wt%) catalyst which is more selective to epoxidation, while at high Au loadings (0.42 wt%) oxidic Au species are observed and he catalyst shows lower epoxide selectivity.