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EN
A group of supported ruthenium catalysts was prepared and tested in methanation of small CO amounts (7000 ppm) in hydrogen-rich streams. High surface area graphitized carbon (484 m2/g) was used as a support for ruthenium and RuCl3 was used as a Ru precursor. Some of the Ru/C systems were additionally doped with barium (Ba(NO3)2 was barium precursor). The catalysts were characterized by the chemisorption technique using CO as an adsorbate. To determine the resistance of the catalysts to undesired carbon support methanation, the TG-MS experiments were performed. They revealed that the barium addition inhibits support losses. The studies of CO methanation (fl ow reactor, atmospheric pressure) have shown that some of the supported ruthenium catalysts exhibit high activities referred to the metal mass. The catalytic properties of ruthenium proved to be dependent on metal dispersion. Some of the Ru/C and Ba-Ru/C systems exhibit higher activity in CO hydrogenation than the commercial nickel-based catalyst.
EN
The effect of chlorine precursor of ruthenium on the dispersion of the metal on the surface of Ru/MgF2 type catalysts has been studied. Results of the dispersion measurements performed by the static method of hydrogen chemisorption have shown that, similarly as for the majority of the known metallic catalysts, the dispersion decreases with ruthenium loading. The results permitted a determination of the optimum conditions for chemisorption measurements on ruthenium catalysts that is the measurement temp. of 100C and equilibrium time of 22 min. The size of the crystallites determined in the chemisorption study was compared with that following from electron microscope observations, and the mean size determined by the latter method proved much smaller than that found by the chemisorption method.
EN
A group of supported ruthenium catalysts was prepared and tested in methanation of small CO amounts (7000 ppm) in hydrogen-rich streams. High surface area graphitized carbon (484 m2/g) was used as a support for ruthenium and RuCl3 was used as a Ru precursor. Some of the Ru/C systems were additionally doped with barium (Ba(NO3)2 was barium precursor). The catalysts were characterized by the chemisorption technique using CO as an adsorbate. To determine the resistance of the catalysts to undesired carbon support methanation, the TG-MS experiments were performed. They revealed that the barium addition inhibits support losses. The studies of CO methanation (fl ow reactor, atmospheric pressure) have shown that some of the supported ruthenium catalysts exhibit high activities referred to the metal mass. The catalytic properties of ruthenium proved to be dependent on metal dispersion. Some of the Ru/C and Ba-Ru/C systems exhibit higher activity in CO hydrogenation than the commercial nickel-based catalyst.
EN
An aerobic oxidation of dibenzothiophene and related compounds using a catalytic amount of ruthenium chloride in hydrocarbon solvents at 80°C for 20 h gave the corresponding sulfones in almost quantitative yields. The reaction might proceed via autoxidation of solvents to hydroperoxides and the reaction of sulfur compounds with the resulting hydroperoxides.
PL
Sulfony otrzymano metodą aerobowego utleniania dibenzotiofenu oraz związków pokrewnych w temperaturze 80°C przez 20 godz. Materiały te otrzymano przy użyciu katalitycznej ilości chlorku rutenu w rozpuszczalnikach wodorowęglowych. Można przypuszczać, że reakcja przebiega następująco: rozpuszczalniki samorzutnie się utleniają do wodoronadtlenków, które potem reagują ze związkami siarki.
PL
W pracy przedstawiono wyniki badań katalizatorów rutenowych naniesionych na binarne nośniki CeO2-Al2O3. Katalizatory otrzymano przez impregnację lub wytrącanie. Temperatura utleniania tlenem wynosiła 370°C. Redukcję wodorem wykonywano w temperaturze określonej przez badania temperaturowo programowanej redukcji. Badane katalizatory charakteryzowano metodami TPR, TPO, XRD. Redukcja układu RuO2/CeO2-Al2O3 ma złożony charakter. Badania TPR wskazują na przebieg redukcji RuO2 z maksymalną szybkością w temperaturze 120-145°C. Obecność rutenu przyspiesza redukcję CeO2. Badania XRD wybranych katalizatorów kalcynowanych oraz redukowanych w różnych temperaturach w zakresie 120-900°C pozwoliły na określenie składu fazowego badanych układów. Określono także wpływ temperatury na wielkość krystalitów CeO2 i naniesionego rutenu. Wykonano testy aktywności katalitycznej badanych układów w reakcji uwodornienia CO2 w zakresie temperatury 50-300°C.
EN
This work presents the results of studies on ruthenium catalysts supported on binary supports CeO2-Al2O3. The catalysts were obtained by impregnation or precipitation. The catalysts under study were characterised by TPR, TPO and XRD methods. The reduction of RuO2/CeO2-Al2O3 system is complex. The reduction of RuO2 is complete already at the low temperatures 120-145°C. Ru promotes the reduction of surface CeO2. XRD studies of chosen catalysts calcined and reduced at different temperatures in the range 120-900°C allowed to identify phase composition of the investigated systems. An influence of temperature on the size of CeO2 crystallites and ruthenium support was also determined. Catalytic activity tests of studied systems in CO2 hydrogenation reaction in temperature range 50-300°C were carried out.
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