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

摘要

Mechanochemical alloying of Cu + Al and Cu + Fe + Al powders with subsequent hydro-thermal treatment and calcination were used to synthesize ceramometal catalysts. In addition, CuAl + Cufoam and CuFeAl + Cufoam 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 CuAl ceramometals are more active toward the low-temperature water-gas shift reaction than CuFeAl. This is related to a higher con-centration 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 unrein-forced ones. This is caused by the developed macropore structure and a higher perme-ability of granules with foam Cu, which weaken the internal diffusion limitations. The maximum activity of the CuAl + Cufoam 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.(c) 2022 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.