Different knitted silica-fibre supported metal oxides (oxides of Co, Ni, Mn, Cr) and various combinations of them, platinum-activated cobalt and nickel oxide catalysts as well as noble metal (Pt, Pd) catalysts were prepared. The catalysts were tested for their activity in propane and natural gas combustion in a continuous flow tube reactor at temperature range of 423-823 K and GHSV of 23900 and 47800 h#x2212;1. High combustion efficiencies were obtained by the metal oxides and platinum activated metal oxides. Co3O4was found to be the most active single metal oxide catalyst in propane combustion. The low temperature activity of metal oxide was strongly improved by use of platinum as an activator. The propane combustion over Pd/SiO2was found to be structure sensitive under our experimental conditions. The dependence of the rate of propane combustion over noble metal containing catalysts was found to be zero order with respect to oxygen and one with respect to propane. The reaction orders over metal oxides were fractional (0 n,m 1). The catalysis were more active in propane than in natural gas combustion. NiO and Pd were found to be the most active catalysts in natural gas combustion. The activity pattern of the prepared catalysts in complete oxidation of propane and natural gas is reported. The catalysts were characterized by O2-TPD and the chemisorption of propane, carbon monoxide and hydrogen.
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