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Activated carbon impregnated with precursor salts of Ba, Co, Cu, Fe, Mg, Mn, Ni, Pb and V and their binary mixtures was used for adsorption of SO2 at 20 °C. The most promising materials for SO2 removal are carbons doped with V, Cu and mainly their binary mixtures, which show a synergetic effect. Kinetic curves and isotherms of SO2 adsorption were obtained at 20 °C. These isotherms are reasonably well fitted by the Langmuir model and the respective parameters were determined. TPD experiments show that adsorption of SO2 increases the oxygenated groups on the carbon surface. The sample doped with V, after SO2 adsorption at 20 °C, presents an increase of basic oxygenated groups, which may be responsible for the observed extra adsorption of SO2. [Copyright &y& Elsevier]

Abstract: Vanadia-titania catalysts prepared by different sol–gel procedures were studied as heterogeneous catalysts for the liquid phase oxidation of limonene. The catalysts were characterized by XRD, XPS, ICP and nitrogen adsorption. According to the XRD results the catalyst samples can be divided in two different groups: anatase samples and anatase+rutile samples. XRD signals of vanadia are not found in the diffractograms. The main reaction products are polymers. Limonene oxide, limonene glycol, carveol and carvone are obtained in small amounts. A number of autoxidation products, alcohols, aldehydes and ketones, are also obtained. The effects of titania composition on the reaction orientation are discussed. [Copyright &y& Elsevier]