| The oxidation of propylene over BiMeVOx catalyst has been investigated. {dollar}rm Bisb2Mosb{lcub}x{rcub}Vsb{lcub}1-x{rcub}Osb{lcub}(11+x)/2{rcub}{dollar} showed similar behaviour to {dollar}rm Bisb2MoOsb6{dollar}; substantial yields of acrolein were observed. A slight maximum (95% as compared to 88%) in acrolein selectivity is observed in the mixed Mo/V compounds when compared with x = 0 and x = 1 materials. Minor amounts of propylene oxide were seen with all catalysts, however, all of the oxide catalysts produced less than the homogeneous gas-phase reaction. The use of hydrogen peroxide as oxidant was studied over an oxide catalyst, over Ag and with an empty reactor. With the oxide catalyst, higher propylene oxide selectivities were observed with hydrogen peroxide than with molecular oxygen while the reverse observation was made with Ag and the empty reactor. It was concluded that the mixed Mo/V materials, like their parent, are incapable of activating O{dollar}sb2{dollar} as a single O atom donor. |
