Reduction and catalytic behaviour of heterobimetallic copper–lanthanide oxides

The reduction of the heterobimetallic copper–lanthanide oxides 2CuO·CeO₂ and 3CuO·Ln₂CuO₄ (Ln = La, Pr, Nd) was studied by H₂-TG/DTA and H₂-TPR. All systems exhibit two main reduction steps accompanied by mass losses in the temperature range 20–1000 °C. The first step was attributed to CuO reduction, whereas the second step is due either to copper reduction in the Ln₂CuO₄ phase with the concomitant formation of Ln₂O₃ or to the surface reduction of CeO₂. The products were characterized by XRD, SEM, EDX, and BET techniques and are better described as supported copper type materials. They were active for the mesityl oxide (4-methyl-2-penten-2-one) gas phase hydrogenation.