Influence of Cu foam framework on the physico-chemical properties and catalytic behavior of Cu(Fe)AlO/Cu(Fe)Al ceramometal granules in WGSR

Mechanochemical alloying of Cu + Al and Сu + Fe + Al powders with subsequent hydrothermal treatment and calcination were used to synthesize ceramometal catalysts. In addition, CuAl + Cu foam and CuFeAl + Cu foam ceramometal catalysts reinforced with Cu foam were also synthesized. The obtained ceramometals are the metallic cores containing copper, iron and aluminum alloys, which are covered with a shell consisting of the oxides of these metals. Structural, microstructural and textural features of the synthesized composite catalysts were studied using XRD, XPS, SEM with EDX, and adsorption-desorption isotherms. It was shown that СuAl ceramometals are more active toward the low-temperature water-gas shift reaction than CuFeAl. This is related to a higher concentration of highly active sites on the surface of these ceramometals. The activity of ceramometal granules reinforced with Cu foam is much higher as compared to unreinforced ones. This is caused by the developed macropore structure and a higher permeability of granules with foam Cu, which weaken the internal diffusion limitations. The maximum activity of the CuAl + Cu foam catalyst granules exceeds that of the CuZnAl oxide catalyst by a factor of 2.5. Thermal conductivity of ceramometal catalysts was estimated to be higher for reinforced ceramometals, reaching 4.5 W/mK. So, the integration with foam Cu leads to an improvement of thermal, textural and catalytic properties of ceramometals. • Porous ceramometals CuAlO/CuAl and CuFeAlO/CuFeAl are integrated with foam Cu. • Integration with foam Cu improves permeability and activity of ceramometal catalyst. • Ceramometal CuAlO/CuAl + Cu foam possesses higher activity than oxide CuZnAl one. • Active centers of CuAlO/CuAl are more active than those of CuFeAlO/CuFeAl and CuZnAl.