Binary Oxides Prepared by Microwave-Assisted Solution Combustion: Synthesis, Characterization and Catalytic Activity

Abstract

Three different alumina-based Ni, Cu, Co oxide catalysts with metal loading of 10 wt %, and labeled 10Ni–Al, 10Co–Al and 10Cu–Al, were prepared by microwave-assisted solution combustion. Their morphological, structural and surface properties were deeply investigated by complementary physico-chemical techniques. Finally, the three materials were tested in CO oxidation used as test reaction for comparing their catalytic performance. The 10Cu–Al catalyst was constituted of copper oxide phase, while the 10Ni–Al and 10Co–Al catalysts showed the presence of “spinels” phases on the surface. The well-crystallized copper oxide phase in the 10Cu–Al catalyst, obtained by microwave synthesis, allowed for obtaining very high catalytic activity. With a CO conversion of 100% at 225 °C, the copper containing catalyst showed a much higher activity than that usually measured for catalytic materials of similar composition, thus representing a promising alternative for oxidation processes.