Peculiar catalytic properties of oxide glass-(ceramics) in epoxidation reactions

Glass-(ceramic) samples were prepared by melting mixtures of Na2O-V2O5-(Al2O3)-P2O5-Nb2O5 in various molar ratios, and their catalytic performances were correlated to the structural, thermal, and electrical properties. The catalysts were tested in an epoxidation reaction, with tert-butyl hydroperoxide in decane and water as oxidants. Samples containing the highest vanadium content are highlighted as the best catalysts (cyclooctene conversion 70-90 %), highly selective towards the desired epoxide (70-80 %). At the same time, high electrical conductivity is observed with the value of similar to 10(-5) S cm(-1) @30 degrees C, which is 4-6 orders of magnitude higher in comparison to other studied samples.