Effect of H2reduction on the catalytic properties of MoO3 with noble metals for the conversions of pentane and propan-2-ol

Abstract

The catalytic properties of H₂-reduced MoO₃ with noble metals for the conversions of pentane and propan-2-ol were studied. No appreciable difference appeared in the pentane isomerization activity and in the propan-2-ol dehydration activity among Pt, Pd, Rh, and Ir/MoO₃ catalysts after reduction at 773 K for 12 h. H₂-Reduced Ru/MoO₃ exhibited lower isomerization and dehydration activities than the other catalysts. The isomerization and the dehydration activities of H₂-reduced Ru/MoO₃ was improved by an increase in the amount of Ru loading, while those of H₂-reduced Pt/MoO₃ changed very little. XRD and TPR studies showed that the reduction process of Ru/MoO₃ varied with the amount of Ru. By contrast, reduction of Pt/MoO₃ involved the formation of a hydrogen molybdenum bronze, H_xMoO₃, irrespective of the amount of Pt. We suggest from these results that reduction of H_xMoO₃ can yield the active phase for pentane isomerization and for propan-2-ol dehydration.