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CuO/MgO system having different compositions was prepared by impregnation method followed by calcination at 400-900 °C. The effect of CuO content, calcination temperature and doping with small amounts of K⁺ species (1-3 mol %) on physicochemical, surface and catalytic properties of the system were investigated using XRD, adsorption of N2 at -196 °C, and conversion of isopropyl alcohol at 150-400 °C using a flow technique. The results revealed that the solids having the formulae 0.2 and 0.3 CuO/MgO calcined at 400 °C consisted of nanosized MgO and CuO as major phases together with Cu₂O as minor phase. The BET-surface areas of different adsorbents are decreased by increasing CuO content, calcination temperature and K⁺- doping. MgO-support material showed very small catalytic activity in 2-propanol conversion. The investigated system behaved as selective catalyst for dehydrogenation of 2-propanol with selectivity > 80%. The catalytic activity increased by increasing CuO content and decreased by increasing the calcination temperature within 400-900 °C. K⁺ - doping increased the catalytic activity and catalytic durability.

The effects of Co 3 O 4 loading, precalcination temperature and ZnO treatment on the catalytic properties of the Co 3 O 4 /Al 2 O 3 system were investigated. The amounts of Co 3 O 4 were varied between 5.57 wt% and 32.0 wt% and the resulting solids subjected to heat treatment at temperatures in the range 400-600ºC. The amounts of ZnO were varied between 0.36 wt% and 2.12 wt%. The results obtained indicated that ZnO treatment of Co 3 O 4 /Al 2 O 3 solids followed by precalcination at 400ºC resulted in a progressive decrease in the particle size of the Co 3 O 4 crystallites in the resulting samples. The catalytic activity of such solids towards H 2 O 2 decomposition decreased progressively as the precalcination temperature employed was increased in the range 400-600ºC. The relationship between the catalytic activity expressed as a plot of the reaction rate constant, k, versus the amount of Co 3 O 4 in the samples showed a progressive increase in the range 5.6-17.7 wt% followed by an abrupt increase when the extent of loading exceeded this limit. Treatment with ZnO effected a measurable increase (42%) in the specific surface area (S BET) of the treated solids. However, such treatment also resulted in a considerable increase in the value of the reaction rate constant for the catalyzed reaction. Thus, the maximum increase in the value of k 20ºC due to doping with 2.12 wt% ZnO attained a value of 543% while the corresponding increase in the value of the reaction rate constant per unit surface area, _ k 20ºC , was 331%. Precalcination at 400-600ºC of Co 3 O 4 /Al 2 O 3 solids subjected to ZnO treatment did not modify the mechanism whereby the catalytically active constituents (surface cobalt species) were involved in the reaction although their concentration was altered without affecting their energetic nature.

The effects of Ag-doping on the physico-chemical, spectral, surface, and catalytic properties of the FeMgO system with various Fe2O3 loadings were investigated. The dopant (Ag) molar ratio varied between 0.01 % and 0.05 %. The techniques employed for characterisation of catalysts were TG/DTG, XRD, ESR, N2 adsorption at −196°C, and catalytic decomposition of H2O2 at 25–35°C. The results obtained revealed that the investigated catalysts consisted of nanosized MgO as the major phase, apart from the MgFe2O4 and/or Fe3O4 phases. ESR result of the FeMgO system revealed the presence of paramagnetic species as a result of Ag-doping. The textural properties including SBET, porosity and St were modified by Ag-doping. The doping process with Ag-species improved the catalytic activity of the FeMgO system. Increasing the calcination temperature from 400°C to 800°C increased the catalytic activity (k*30 °C) of 0.05 AgFeMgO in H2O2 decomposition by 21.2 times.