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Abstract  

Cu–Cr and Co–Cr oxide systems supported on Al2O3 and Al2O3 + SiO2 were studied in order to find the appropriate combination as a catalyst for the reduction of NO with CO with respect to the active phase and the nature of the support. The catalysts were prepared by successive impregnation of the support with solution mixtures of tartaric acid and nitrate. The catalysts were characterized by atomic absorption spectroscopy (AAS), Brunauer, Emmett, Teller (BET), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) methods. The copper–chromium catalysts are more active than the cobalt–chromium ones. The catalysts supported on Al2O3 + SiO2 are more active than the supported on pure alumina. The probable reasons are the higher content of copper and cobalt on the surface of Al2O3 + SiO2 and a formation of less active in the studied reaction copper and cobalt aluminates on the alumina supported catalysts.

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to gold catalysts. The increases in the particle size observed on Nb 2 O 5 can be explained considering its lower surface area and deposition mechanism of colloids over the support. On Nb 2 O 5 supported catalysts, the addition of gold to iridium

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, Piedigrosso P, Colomer JF, Mukhopadhyay K, Doome R et al. Synthesis of single- and multi-wall carbon nanotubes over supported catalysts, Appl. Phys. A 1998; 67: 11–22. Doome R. Synthesis of

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Introduction The Fischer–Tropsch (FT) synthesis is a process of hydrocarbon production from carbon monoxide and hydrogen. Cobalt-supported catalysts are currently preferred over Fe-based systems due to their superior

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. The interaction of Pd with Mn 2 O 3 results in good catalytic activity of the catalyst. The catalytic activity of the doped catalysts was compared with supported catalysts. Stability studies were performed and the catalytic activity was tested in the

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prone to recycling difficulty [ 10 ], though this type of catalyst has shown excellent catalytic performance in homogeneous reactions with a wide variety of substrates [ 11 ]. Generally, supported catalysts are simply prepared by the impregnation of

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homogeneous catalysts and simultaneously avoiding its disadvantages like handling and reusability. These supported catalysts have often shown high catalytic activities in comparison to unsupported analogues due to the better interaction of active sites with

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Fischer–Tropsch synthesis, isomerization, esterification reactions [ 8 , 9 ], synthesis of biodiesel and catalytic purification of automobile exhaust, etc. [ 10 , 11 ]. Research indicates that the performance of zirconia supported catalysts is superior

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on continuous flow processes using scCO 2 and supported catalysts, see: (a) Stouten , S. C. ; Noël , T. ; Wang , Q. ; Hessel , V. Chem. Eng. Process. 2014 , 83 , 26 – 32 ; (b

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. Obviously, the metal loading was controlled at 3.0 wt%. After loading, compared with activated carbon, the BET surface area of supported catalysts decreased slightly, since the metal with big particle size partially blocked the micro-pores in the activated

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