Ceria-Praseodymia Mixed Oxides: Relationships Between Redox Properties and Catalytic Activities Towards NO Oxidation to NO2 and CO-PROX Reactions
| Autor: | Noelia Guillén-Hurtado, José Juan Calvino-Gámez, Xiaowei Chen, Avelina García-García, Javier Giménez-Mañogil, Susana Fernandez-Garcia |
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| Přispěvatelé: | Universidad de Alicante. Departamento de Química Inorgánica, Universidad de Alicante. Instituto Universitario de Materiales, Materiales Carbonosos y Medio Ambiente |
| Rok vydání: | 2016 |
| Předmět: |
CO-PROX
Química Inorgánica Chemistry Inorganic chemistry PROX Ceria-praseodymia 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Alkali metal Mass spectrometry 01 natural sciences Redox Catalysis 0104 chemical sciences Thermogravimetry Lattice oxygen Catalytic oxidation NO oxidation Molecule 0210 nano-technology Redox properties |
| Zdroj: | RUA. Repositorio Institucional de la Universidad de Alicante Universidad de Alicante (UA) |
| ISSN: | 1572-9028 1022-5528 2015-6480 |
| Popis: | A series of CexPr1−xO2−δ catalysts was prepared by co-precipitation method in alkali media. These catalysts were characterized by N2 adsorption–desorption isotherms at −196 °C, X-ray diffraction, thermogravimetry combined with mass spectrometry (TG-MS), and temperature-programmed reduction with H2 and CO (H2-TPR and CO-TPR, respectively). Catalytic tests were performed for temperature programmed NO oxidation to NO2 (from 25 to 750 °C) and for the preferential oxidation of CO in H2 rich stream (CO-PROX reaction) in the range of 150–500 °C. The trends in the order of catalytic activities towards NO oxidation and CO-PROX are correlated with the redox properties of the catalysts and their composition. CexPr1−xO2−δ mixed oxides present very different catalytic behaviours towards NO oxidation and CO-PROX reactions. These experimental trends might be explained by the balance of several factors: the acid character of the NO and CO molecules, the different lattice oxygen mobility of the catalysts, the presence of surface carbonates species in the samples, and the catalysts’ reducibility under H2 and CO. The understanding of the features that govern the activity towards these environmentally relevant oxidation reactions is important in the designing of effective catalysts. The authors gratefully acknowledge the financial support of Generalitat Valenciana (PROMETEOII/2014/010), MINECO (CTQ2015-64801-R, MAT2013-40823-R, CSD2009-00013) and the UE (FEDER funding). X. Chen thanks the program of “Ramón y Cajal” from Ministry of Science and Innovation of Spain. |
| Databáze: | OpenAIRE |
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