"Structured catalysts" » "Structured catalyst"
Publication Date: 2013.
Metallic supported structured catalysts were obtained by washcoating AluchromYHf monoliths with an Au/TiO2 catalyst. The powder catalyst was synthesized by DAE (direct anionic exchange) method. Using this catalyst, a stable slurry was prepared and used to washcoat the monoliths. TEM and SEM studies revealed that gold nanoparticles in the Au/TiO2 powder catalyst had an average diameter of 3–4 nm, but during the preparation of the structured catalyst, aggregate Au particles of the slurry reached diameters of 9 nm. Before coating, Aluchrom YHf monoliths were thermally treated to generate a homogeneous and well-adhered oxide rough surface layer, mainly composed of -Al2O3 whiskers, which favored the anchoring of the catalyst. The catalytic layer deposited was well attached and contained not only the Au/TiO2 catalyst but also metallic oxides formed from stainless steel components that diffused through the oxide scale. The structural characterization was performed by XRD, XRF, TEM, SEM, GD-OES and SBET.<br />The catalytic activity of the powder and structured catalysts was tested in the oxidation of the CO<br />reaction. Catalysts demonstrated to be active at room temperature. After a first activation run, and in spite of their larger gold particle size, the catalytic activities of the structured catalysts overcame those of the powder catalyst. This improvement is probably due to the segregation of the transition metal oxides toward the surface oxide scale.
Author affiliation: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentina
Author affiliation: Ivanova, S.. Universidad de Sevilla; España
Author affiliation: Sanz, O.. Universidad de Sevilla; España
Author affiliation: Domínguez, M. I.. Universidad de Sevilla; España
Author affiliation: Corrales, A.. Universidad de Sevilla; España
Author affiliation: Odriozola, J.A.. Universidad de Sevilla; España
Author affiliation: Centeno, M.A.. Universidad de Sevilla; España
Repository: CONICET Digital (CONICET). Consejo Nacional de Investigaciones Científicas y Técnicas