System on Propane Selective Oxidation

A catalytic system Mo-V-Nb-W supported on alumina was prepared by impregnation and investigated for the selective oxidation of propane. The effects of the variation of each metal and of the catalyst preparation were analysed. The results show that Mo and V species supported on alumina can lead to catalysts with high selectivity to propene and reasonable selectivity to acrolein. The presence of Nb and W seems to have little effect. The catalyst can be affected by the method of impregnation. 

Catalyst preparation. One library of catalysts, indicated below with the name Library 1, was prepared by wet impregnation to have a range of concentrations 

A second library of six catalysts, shown in Table 2, codes FI to F6, was prepared to examine the effect of varying the method and sequence used for the impregnation process in this series, the samples contained only Mo and V at nominally identical concentrations (with a ratio Mo/V of ca. 6), with V approx 1% (but not comparable with previous series). Two additional samples, F7 and F8, were prepared to show any effects of including Nb and W (each in amount of ca. 1%) in this formulation. 

The samples FI, F2, F3, F7 and F8 were prepared by wet impregnation using excess solutions as above the preparation of FI, F7 and F8 involved feeding the support with each solution in turn before finally drying and calcining (as for the samples of Table 1) whereas F2 and F3 involved drying and calcining before addition of the second component. In contrast, samples F4, F5 and F6 

Sample Code Metal oxides (nominal w/w%) Impregnation method Sequence 

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