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| MOURA, C. V. R.; NERES, H. L. S.; LIMA, M. G.; MOURA, E. M.; MOITA NETO, J. M.; OLIVEIRA, J. E. de; LIMA, J. R. O.; SITTOLIN, I. M.; ARAUJO, E. C. E.. |
| In this work, it was described the preparation and the characterization of a solid acid catalyst obtained by the mixture of Cr/Al oxides (CRAL). The catalyst was tested in the transesterification reaction of babassu oil with 5% of free fatty acid (FFA). The results of textural and acidity characteristics of CRAL were: area (56 m2 g-1), pore size (7.0 μm), total acidity (182.28 μmol g-1), wherein Brönsted sites are the most active. Powder X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) show three phases of the catalyst (Cr2O3/Na2Cr2O3/Al2O3), 0.25:0.25:0.50, respectively. The reaction reached conversion about 98.6% under the conditions: alcohol/oil molar ratio (24:1), catalyst... |
| Tipo: Artigo em periódico indexado (ALICE) |
Palavras-chave: Óleo de babaçu; Cinética; Reutilização; Heterogeneidade; Biocombustível; Catalisador; Lixiviação; Biodiesel; Catalyst; Babassu oil; Kinetic; Reusability; Leaching; Heterogeneity. |
| Ano: 2015 |
URL: http://www.alice.cnptia.embrapa.br/handle/doc/1030158 |
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| Carvalho,Marta C. N. A.; Perez,Carlos A.; Simão,Renata A.; Passos,Fabio B.; Schmal,Martin. |
| Silver supported catalysts on alpha-alumina were prepared and characterized by Brunauer-Emmet-Teller equations, scanning electronic microscopy, X-ray diffraction and atomic force microscopy techniques. Results show that these are powerful techniques for the determination of texture, morphology and surface properties. It has been shown that the addition of Cs in the Ag/Al2O3 catalyst increased the dispersion of silver with the formation of small silver particles over a thin silver film already formed over the alumina support. It is important to stress that atomic force microscopy measurements are significant to observe the film and the dispersion of Ag and, on the contrary, X-ray photoelectronic spectroscopy did not, however, it allows to the conclusion... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Silver; Cesium; Catalyst; AFM; XPS. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000100003 |
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