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Reaction Kinetics, Mechanisms and Catalysis
Authors: Jung-Nam Park, Jeong Kuk Shon, Mingshi Jin, Soo Sung Kong, Kiyoung Moon, Gwi Ok Park, Jin-Hyo Boo, and Ji Man Kim

], CuMn 2 O 4 [ 6 ], and Au [ 7 , 8 ] catalysts are active towards CO oxidation at room temperature. It has been also reported that pretreatment in an oxidative atmosphere results in the improvement of catalytic activity for CO oxidation by forming

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field. A number of studies have demonstrated that supported noble metal (such as Au and Pt) catalysts have high catalytic activities for low-temperature CO oxidation [ 1 , 2 ]. However, due to high prices and the scarcity of noble metals, attention has

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Iwona Tomska-Foralewska, Wiesław Przystajko, Mariusz Pietrowski, Michał Zieliński, and Maria Wojciechowska

Abstract  

Novel magnesium oxo-fluoride supports containing different amounts of MgO, prepared by the sol–gel method have been proposed for the synthesis of gold catalysts. The MgF2–MgO supports have mesoporous structure and their surface area is a few times larger than those of pure MgF2 or pure MgO. Gold catalysts have been prepared by impregnation of the MgF2–MgO supports with HAuCl4 in the amount corresponding to 1 wt.% Au. The gold catalysts has been characterized by XRD, TEM measurements and the catalytic activity in CO oxidation at temperatures 30–300 °C have been performed. The Au/MgF2–MgO catalysts show higher activities (depending on the content of MgO in the support) as compared to Au/MgF2 and Au/MgO prepared under the same conditions. Their activities fall into the upper range of gold catalysts supported on other carrier reported in literature.

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has resulted in an extensive research in CO oxidation catalysis. Many catalyst systems including noble metals, metal oxides and composites, have been studied for high CO conversion at various temperatures and reaction environments. Among them, metal

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determine the effect of H 2 on CO oxidation kinetics [ 2 , 11 – 13 ]. Under PROX conditions, the CO and O 2 reaction orders were found as 0.58 and 0.23, respectively, over Au/α-Fe 2 O 3 [ 2 ]. The discrepancy observed between these results and those of

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catalytic activity of the Ce–Zr–O solid solution on low-temperature CO oxidation, water–gas shift reaction and preferential oxidation of CO in excess hydrogen [ 19 ], and surfactant-assisted one-step prepared CuO/Ce 0.8 Zr 0.2 O 2 catalysts with mesoporous

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, M. Scurtu, S. Mihaiu, M. Caldararu, and M. Zaharescu

-activity catalysts [ 9 , 10 ]. For example, Ce 0.8 Sn 0.2 O 2 and Ce 0.3 Sn 0.7 O 2 mixed oxides were found to have higher CO oxidation activity and lower values of activation energy as compare to SnO 2 and CeO 2 single oxides [ 9 ]. A similar conclusion was

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became a more and more serious problem around the industrialized countries, SnO 2 -based catalysts, which were modified by various precious and base metal oxides, have been studied as catalysts for CO oxidation, hydrocarbon combustion and some other types

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Abstract  

Nano-particle, pure and CuOx-modified, fluorite-structured cubic-CeO2 were successfully synthesized with surface areas near 240 m2/g applying a microemulsion method with mixed templating surfactants (viz. DDAB and Brij®35). Following calcination at 400–800 °C, the products were characterized by X-ray powder diffractometry, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy, and, then, tested as catalysts for methylbutynol decomposition and CO oxidation in the gas phase. Results obtained showed the pure and CuOx-modified cerias to exhibit comparable activities towards the alcohol decomposition into acetone and acetylene, but the modified ceria exhibited considerably higher activity towards the CO oxidation than the pure one. The calcination product of CuOx-modified ceria at 800 °C was capable of lowering the light-off temperature of the CO oxidation from 300 °C (on the pure) down to 70 °C. Surface chemical consequences of the CuOx-modification, viz. increasing the Ce(III)/Ce(IV) atomic ratio, as well as the establishment of Cu(I) and Cu(II) sites, have been allocated the responsibility of the observed upsurge of the CO oxidation activity.

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