In this study, we investigate materials based on ruthenium combined with tungsten and phosphorus (Fig. ) as an alternative class of catalysts for selective oxidation. Platinumgroup-metal-based catalysts commonly result in hydrocarbon combustion products (Fig. ). The combination of these metals with tungsten and phosphorus, in a tungsten-phosphate-like matrix, however, could favor the selectivity towards the desired olefins and oxygenates, following a catalyst design strategy based on the dilution of highly active metal sites. With the aim of studying these systems, HTE measurements were performed using 120 different three-component catalyst compositions containing ruthenium, tungsten and phosphorus in different proportions. At each catalyst composition, several reaction temperatures between 200ºC and 400ºC were examined. The detailed preparation, characterization and reactivity analysis of these catalysts in the selective oxidation of n-butane, propane and propylene is discussed in a separate contribution. In this paper, we only provide details on the propylene selective oxidation reaction. All the reactions were carried out in tubular, fixed-bed reactors with the following reaction feed: Ar, H2O, N2, O2 and propylene (C3H6) with molar rates 4.015, 4.015, 104.40, 20.08, and 1.57 mmol/h, respectively. The same mass of catalyst was used in all reactions, so that the contact time, in terms of volumetric flow per mass of catalyst, was kept fixed across experiments. These three-component catalysts are prepared on a SiO2 pseudo-liquid support and might present a disordered, possibly amorphous, structure. The atomic structures of all the tested catalysts are not known in detail. However, similar catalytic performance was found for crystalline and disordered phases at the same composition. This indicates that the composition is more crucial for the catalytic performance than the degree of crystallinity.