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Abstract: Hydrotalcite originated Cu–Mg–Al, Co–Mg–Al and Cu–Co–Mg–Al oxide systems were tested as catalysts for the total oxidation of mono-carbon VOCs (methane, methanol, and formic acid). Both calcination temperature of the hydrotalcite precursors as well as doping of the catalysts with potassium promoter influenced their catalytic activity. Increased calcination temperature, which resulted in a decrease of the surface area of the samples and formation of the spinel phases, activated the Co–Mg–Al catalyst, while the opposite effect was observed for the Cu–Mg–Al and Cu–Co–Mg–Al catalysts. On the other hand doping of the catalysts with potassium promoter significantly activated the Cu–Mg–Al and Cu–Co–Mg–Al catalysts in the processes of methanol and formic acid conversion, while only slightly influenced the catalytic performance of the Co–Mg–Al sample. [Copyright &y& Elsevier]

Abstract: This study examined the catalytic behavior of La–Ba–Ni catalysts regarding the total oxidation of five CVOCs. The experimental results demonstrate that La–Ba–Ni catalysts are superior in suitability for the total oxidation of CVOCs. More than one Ba(3d5/2), La(3d5/2), and Ni(2p1/2) peaks appeared in each XPS spectrum due to a chemical shift to a higher binding energy. Since the electropositivity of Ba is higher than that of Ni, chloride is transferred from the Ni-site to the Ba-site with ease, thereby enhancing activity. [Copyright &y& Elsevier]

Abstract: Co and Ni ferrospinels were prepared by coprecipitation and by mechano-chemical method, characterized using XRD, N2 adsorption, EDX and H2-TPR techniques and tested in the catalytic total oxidation of propane within the temperature range of 250–600°C. Depending on the ferrospinel composition, the method of preparing it and the reaction conditions, total conversion to CO2 was observed at temperatures between 400°C and 500°C. The best results were obtained with the Co ferrite catalyst prepared by coprecipitation, which gives total conversion at temperatures as low as 400°C. The ferrospinel catalysts showed a good stability during the catalytic test. [Copyright &y& Elsevier]

Abstract: Pt–MCM-41 materials were synthesized by a simple method via simultaneous self-assembling and Pt incorporation, using cetyltrimethylammonium chloride (CTAC) as a structure directing agent. Sample characterization was performed by N2 sorption, XRD, TEM and high-resolution TEM (HRTEM) measurements. The highly ordered structure of MCM-41 was not appreciably affected by the formation of the Pt particles well dispersed in the MCM-41 as cubic nano-crystallite of ca. 10nm. The Pt–MCM-41 sample was tested as a highly active catalyst towards complete oxidation of toluene. High surface area, well dispersed Pt, and appropriate Pt crystallite size may answer for the excellent catalytic performance. [Copyright &y& Elsevier]