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The synthesis, structural characterization and the surfactant behavior of a new family of chiral reactive surfactants derived from glucose are presented. N-alkylglucosylmethacrylamides and N-alkylglucosylacrylamides are prepared using a two-step process from glucose without protection. 2D NMR and ID spectroscopy are used to study the structures which reveal the existence of a rotational isomerism that is strongly dependent on the steric hindrance of the carbonyl substituent.

In the following work, the catalytic behavior of Pd catalysts prepared using different oxides as support (Al2O3, CeO2 and TiO2) in the catalytic combustion of propene, in low concentration in excess of oxygen, to mimic the conditions of catalytic decomposition of a volatile organic compound of hydrocarbon-type is reported. In addition, the influence of different promoters (Ce, Ti, Fe and Mn) when added to a Pd/Al2O3 catalyst was analyzed. Catalysts were prepared by the impregnation method and were characterized by ICP-OES, N2 adsorption, temperature-programmed reduction, temperature-programmed oxidation, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. Catalyst prepared using CeO2 as the support was less easily reducible, due to the stabilization effect of CeO2 over the palladium oxides. Small PdO particles and, therefore, high Pd dispersion were observed for all of the catalysts, as confirmed by XRD and TEM. The addition of Ce to the Pd/Al2O3 catalysts increased the metal-support interaction and the formation of highly-dispersed Pd species. The addition of Ce and Fe improved the catalytic behavior of the Pd/Al2O3 catalyst; however, the addition of Mn and Ti decreased the catalytic activity in the propene oxidation. Pd/TiO2 showed the highest catalytic activity, probably due to the high capacity of this catalyst to reoxidize Pd into PdO, as has been found in the temperature-programmed oxidation (TPO) experiments. [ABSTRACT FROM AUTHOR]

Abstract: The selective catalytic reduction of NO by n-decane (C10H22-SCR), with or without water (1.5vol.%), has been studied over sulphated titania catalysts (∼2wt% S). Such sulphated materials have been explored as candidates for HC-SCR by decane with process temperatures >600°C. The nature of the functional groups from residual reaction products and the thermal stability of sulphated compounds were characterized by mass spectroscopy, FTIR analysis and temperature programmed desorption experiments. It was observed that hydrocarbons (C x H y ), aldehyde (RCHO), acid (RCOOH), ester (RCOOR) and primary and secondary amine (RNH2, R2NH) functional groups were present at the catalyst surface. For the sample not tested under HC-SCR reaction, the sulphate compounds (SO4 2−, SO3 2−) were stable up to 600°C under He-TPD whereas for samples tested under the HC-SCR reaction, sulphate species were released above 400°C. This might be due to the exothermic oxidation reaction of deposited carbon compounds, characterized by ex situ analysis, with oxygen supplied by the sulphated support. This effect was confirmed by mixing the catalyst with soot particles. Lastly, we propose a reaction scheme for the HC-SCR of NO by decane over sulphated titania. [Copyright &y& Elsevier]

Highlights: [•] LaMnO3 were synthesized by three different methods, citrate sol–gel, glycine combustion and co-precipitation. [•] LaMnO3 synthesized by citrate sol–gel exhibited the best catalytic performance for toluene oxidation. [•] No by-products were formed but only CO2 and H2O. [•] Specific surface area, reducibility and surface adsorbed oxygen were the main parameters. [•] Apparent activation energies of all samples correlated well with their catalytic activities. [ABSTRACT FROM AUTHOR]