| Journal: | Brazilian journal of chemical engineering |
| Database: | PERIÓDICA |
| System number: | 000309002 |
| ISSN: | 0104-6632 |
| Authors: | Batista, M.S1 Melo, R.A.A2 Wallau, M Urquieta González, E.A |
| Institutions: | 1Universidade Federal de Sao Carlos, Departamento de Engenharia Quimica, Sao Carlos, Sao Paulo. Brasil 2Centro Universitario do Sul de Minas, Laboratorio de Catalise e Desenvolvimento de Materiais, Varginha, Minas Gerais. Brasil |
| Year: | 2005 |
| Season: | Sep |
| Volumen: | 22 |
| Number: | 3 |
| Pages: | 433-442 |
| Country: | Brasil |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Experimental |
| English abstract | Propane oxidation and reduction of NO to N2 with propane under oxidative conditions on a Cu-Al-MCM-41 mesoporous molecular sieve and Cu-ZSM-5 zeolites were studied. Both types of catalysts were prepared by ion exchange in aqueous solutions of copper acetate and characterised by X-ray diffraction (XRD), nitrogen sorption measurement, diffuse reflectance ultra-violet spectroscopy (DRS-UV), diffuse reflectance infra-red Fourier transform spectroscopy (DRIFTS) of the adsorption of CO on Cu+ and temperature-programmed reduction with hydrogen (H2-TPR). The NO reduction was performed between 200 and 500 ºC using a GHSV = 42,000 h-1. H2-TPR data showed that in the prepared Cu-Al-MCM-41 all the Cu atoms are on the surface of the mesopores as highly dispersed CuO, which results in a decrease in specific surface area and in mesopore volume. H2-TPR together with DRIFTS data provided evidence that in Cu/ZSM-5 catalysts, Cu atoms are found as two different Cu2+ cations: Cualpha2+ and Cubeta2+, which are located on charge compensation sites, and their thermo-redox properties were different from those of Cu atoms in Cu-Al-MCM-41. The specific activity of the Cu2+ exchangeable cations in Cu-ZSM-5, irrespective of their nature, was much greater than that of the Cu2+ in Cu-Al-MCM-41, where they are found as CuO |
| Disciplines: | Química |
| Keyword: | Ingeniería química, Catálisis, Tamices moleculares, Propano, Oxidación, Oxido nitroso, Reducción, Zeolitas |
| Keyword: | Chemistry, Chemical engineering, Catalysis, Molecular sieves, Propane, Oxidation, Nitrous oxide, Reduction, Zeolites |
| Full text: | Texto completo (Ver HTML) |
