Synthesis and characterization of H-ZSM-5/[Al]MCM-41microporous-mesoporous hybrid materials
Palavras-chave:
molecular sieves, microporous-mesoporous hybrid, synthesis, characterizationResumo
In this work, H-ZSM-5/[Al]MCM-41 hybrid material was prepared by using a as-synthesized H-ZSM-5 zeolite, using CTABr as structure directing agent. X-ray diffraction confirmed the preservation of the MFI phase (ZSM-5), while the formation of the hexagonal mesophase (MCM-41) was also observed, resulting in the combination of both structures in the hybrid material. Thermal analysis enabled the identification of the appropriate calcination temperature for the complete removal of CTA⁺. The SiO2/Al2O3 molar ratios determined by XRF were 24.6, 32.2, and 23.8, respectively, for H-ZSM-5, MCM-41 and the hybrid. The SEM micrographs revealed hexagonal polyhedral crystals for H-ZSM-5, a tubular morphology for [Al]MCM-41 and the hybrid appears to be an interwoven mixture of the two morphologies. Nitrogen physisorption showed BET surface areas of 343, 854, and 483 m2g-1, and the hybrid exhibited 16.3% micropores and 83.7% mesopores. These materials are promising as catalysts or catalyst supports.
Referências
1. Y. Liu; W. Zhang; T. J. Pinnavaia. J. Am. Chem. Soc. 2000, 122, 8791.
2. H. Kosslick; G. Lischke; G. Walther; W. Storek; A. Martin; R. Fricke. Microporous Mater. 1997, 9, 13–33.
3. T. Prasomsri; W. Jiao; S.Z. Weng; J. Garcia Martinez; Chem. Commun. 2015, 51, 8900–8911.
4. Y. Lui; T. J. Pinnavala. Chem. Matter. 2002, 14, 3.
5. S. Ramírez; J. M. Domínguez; L. A. García; M. A. Mantilla; C. A. Flores; J. Salmones; D. Jerónimo. Petrol. Sci. Technol. 2004, 22, 119-127.
6. P.F. Corregidor, P.M. Cuesta, D.E. Acosta, H.A. Destéfanis, Appl. Catal. A Gen. 2019, 587, 117262.
7. M.B. dos Santos, K.C. Vianna, H.O. Pastore, H.M. Andrade, A.J. Mascarenhas. Micropor. Mesopor. Mat. 2020, 306, 110413.
8. H.O. Pastore, M. Munsignatti, D.R. Bittencourt, M.M. Rippel. Micropor. Mesopor. Mat. 1999, 32, 211.
9. J.C. Vartuli; W.J. Roth; J.S. Beck; S.B. McCullen; C.T. Kresge. in Synthesis, Springer Berlin Heidelberg, 2001, 97.
10. N. La-Salvia; J.J. Lovón-Quintana; A.S.P. Lovón; G.P. Valença. Mater. Res. 2017, 20, 1461.
11. J.M.D. Cónsul; C.A. Peralta; E.V. Benvenutti; J.A. Ruiz; H.O. Pastore; I.M. Baibich. J. Mol. Catal. A: Chem. 2006, 246, 33.
12. J. Rouquerol; F. Rodríguez-Reinoso; K.S.W. Sing. Characterization of Porous Solids III, Elsevier, Amsterdam, 1994.
