dc.contributor | Universidade Federal de São Carlos (UFSCar) | |
dc.contributor | Universidade Estadual de Campinas (UNICAMP) | |
dc.contributor | Universidade Estadual Paulista (Unesp) | |
dc.date.accessioned | 2015-03-18T15:53:41Z | |
dc.date.available | 2015-03-18T15:53:41Z | |
dc.date.created | 2015-03-18T15:53:41Z | |
dc.date.issued | 2015-01-15 | |
dc.identifier | Microporous And Mesoporous Materials. Amsterdam: Elsevier Science Bv, v. 202, p. 198-207, 2015. | |
dc.identifier | 1387-1811 | |
dc.identifier | http://hdl.handle.net/11449/116664 | |
dc.identifier | 10.1016/j.micromeso.2014.09.058 | |
dc.identifier | WOS:000346211600025 | |
dc.identifier | 6466841023506131 | |
dc.identifier | 0000-0002-3823-0050 | |
dc.description.abstract | The zeolite with BEA structure has been obtained using different Al amounts in the presence of tetraethylammonium as a structure directing agent. The effect of the Si/Al molar ratio on the crystal size, morphology, yield, chemical composition and catalytic properties was investigated. The materials have been characterized towards zeolitic properties by XRD, SEM, EDS, TGA, Si-29 MAS-NMR, XPS and TEM. The chemical composition of the crystals depends on the concentration of the initial reaction mixture and that a decrease in the Al content is associated with an increase in particle size. The characterization by TGA/DTA of as-synthesized zeolites with BEA structure showed that an increase of Si content resulted in the formation of [=Si-O-][TEA(+)] species, this was supported by Si-29 MAS-NMR. The XPS results also showed that the chemical composition of the surface differed from that of the bulk material, this was supported by TEM/EDS results. The results of catalytic activity tests indicated that a fraction of the [=Si-O-][TEA(+)]species was present on the external surfaces of the crystals, although the largest fraction appeared to be in the interior of the particles. As-synthesized BEA zeolite showed good catalytic activity and suggests that this material can be applied in other reactions involving basic sites. (C) 2014 Elsevier Inc. All rights reserved. | |
dc.language | eng | |
dc.publisher | Elsevier B.V. | |
dc.relation | Microporous And Mesoporous Materials | |
dc.relation | 3.649 | |
dc.relation | 1,080 | |
dc.rights | Acesso restrito | |
dc.source | Web of Science | |
dc.subject | Hydrothermal synthesis | |
dc.subject | BEA structure | |
dc.subject | Siloxy species | |
dc.subject | Basic catalysis | |
dc.subject | Knoevenagel condensation | |
dc.title | As-synthesized TEA-BEA zeolite: Effect of Si/Al ratio on the Knoevenagel condensation | |
dc.type | Artículos de revistas | |