Thermally synthesized nanosized copper ferrites as catalysts for environment protection

Nanosized copper ferrites were prepared by thermal method from the corresponding hydroxide carbonate precursors varying the temperature of synthesis. The phase composition of the obtained materials was characterized by XRD, Mössbauer spectroscopy, DSC and TPR analysis. Their catalytic properties were tested in total oxidation of toluene and methanol decomposition to CO and hydrogen. The relation between the synthesis parameters, phase composition of the samples and their transformation under the oxidation or reduction reaction medium was investigated in turns to understand the catalytic behavior of the obtained materials.

The catalytic behavior of the obtained ferrites depends not only on their initial phase composition, but on the phase transformations due to the influence of the reaction medium.Figure optionsDownload as PowerPoint slideResearch Highlights
► The phase composition of thermally synthesized copper ferrites depends on the annealing temperature, with a tendency to tetragonal structure formation over the cubic one at higher temperatures.
► Under the oxidation reaction atmosphere during the total oxidation of toluene, the catalytic activity of the samples decreases with the formation of tetragonal ferrite phase.
► Under the reduction reaction atmosphere during the methanol decomposition to CO and methane, complex phase transformation to Cu, CuO, magnetite and carbide, which reflects on the catalytic activity and selectivity, is observed.