Physicochemical, surface and catalytic properties of nanosized copper and manganese oxides supported on cordierite

Nanosized CuO, Mn2O3 and a mixture of both oxides supported on cordierite were prepared by wet impregnation followed by calcination at 350–700 °C. The prepared sampled were characterized by using XRD, EDX, nitrogen adsorption at −196 °C and CO-oxidation by O2 at 250 °C. The results revealed that heating the supported mixed oxides at temperatures starting from 500 °C resulted in a solid–solid interaction between some of CuO and Mn2O3 yielding copper manganite (CuMn2O4) the amount of which increased by heating at 700 °C. EDX investigation showed that the surface concentration of copper and manganese species in individual supported oxides loaded on cordierite much decreased by increasing the calcination temperatures. Opposite trends manifested in case of mixed oxides supported solids. The BET-surface areas and catalytic activity were much increased by loading individual oxides and/or a mixture of both oxides on cordierite support material. The activity of binary oxides supported on cordierite was found to increase progressively by increasing their calcination temperature within 350–700 °C, opposite to the individual oxide supported catalyst.

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► Cordierite is devoted with high thermal stability and low thermal expansion coefficient.
► Cordierite is commonly used as a catalyst support for a variety of transition metals.
► CuO, Mn2O3 and a mixture of both on cordierite are active solids for CO oxidation.
► Temperature of heat treatment may modify the catalytic activity of supported catalysts.
► The activity of individual and binary supported oxides may be different from each other.