Catalytic abatement of trichloroethylene over Mo and/or W-based bronzes
| Autor: | J.M. López Nieto, M. D. Soriano, Antonio E. Palomares, N. Blanch-Raga, Patricia Concepción, Joaquín Martínez-Triguero |
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| Rok vydání: | 2013 |
| Předmět: |
Thermal desorption spectroscopy
Process Chemistry and Technology Inorganic chemistry chemistry.chemical_element Infrared spectroscopy Catalytic oxidation Chlorinated VOCs Mo–W–O mixed oxides bronzes Tungsten INGENIERIA QUIMICA Catalysis Trichloroethylene Adsorption chemistry Atomic ratio Temperature-programmed reduction General Environmental Science |
| Zdroj: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia instname |
| ISSN: | 0926-3373 |
| DOI: | 10.1016/j.apcatb.2012.10.016 |
| Popis: | [EN] In this paper we present the results of the synthesis, characterization and catalytic behaviour of Mo(W)¿Nb¿V¿O mixed metal oxides bronzes for the catalytic oxidation of trichloroethylene. The catalysts were prepared hydrothermally with different Mo/W/Nb/V/P atomic ratio and heat-treated at 500 and 700 °C. They were characterized by several techniques as N2-adsorption, X-ray diffraction, FTIR, SEM-EDS, temperature programmed desorption, temperature programmed reduction, UV¿vis, Fourier transformed infrared spectroscopy of adsorbed pyridine and 18O/16O isotope exchange. X-ray diffraction patterns (XRD) of samples heat-treated at 500 °C suggest the presence of a semi-crystalline material with a diffraction peak at ca. 2¿ = 22.2°, while XRD patterns of samples heat-treated at 700 °C show the formation of a tetragonal tungsten bronze (TTB) structure. The activity for the catalytic abatement of trichloroethylene strongly depends on the heat-treatment temperature and the catalyst composition. Thus, samples with W/(Mo + W) atomic ratios of 0.25-0.75 and heat-treated at 500 °C are the most active ones. The enhanced activity has been related to the remarkable higher surface area of the catalyst and to the catalyst composition which influences the acid characteristics as well as the reducibility and reoxidation of the catalysts. The importance of the oxygen dissociation on the catalyst surface and the diffusion of oxygen species through the catalyst are also discussed. The authors wish to thank DGICYT in Spain (Project CTQ2009-14495 and CSD2009-00050-CONSOLIDER/INGENIO 2010) and Universitat Politecnica de Valencia for the financial support. N.B.R. acknowledges Catedra Cemex Sostenibilidad (UPV) for a fellowship. M.D.S. acknowledges Universitat Politecnica de Valencia for a fellowship. |
| Databáze: | OpenAIRE |
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