High-Temperature Synthesis of Ordered Mesoporous Aluminosilicates from ZSM-5 Nanoseeds with Improved Acidic Properties
Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Straße 29a, 18059 Rostock, Germany
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Nanomaterials 2014, 4(3), 712-725; https://doi.org/10.3390/nano4030712
Received: 6 June 2014 / Revised: 4 August 2014 / Accepted: 5 August 2014 / Published: 18 August 2014
(This article belongs to the Special Issue Ordered Mesoporous Nanomaterials)
Ordered mesoporous SBA-15 analogs with different Si/Al ratios were successfully prepared in a two-step process from self-assembly of ZSM-5 nanoseeds at high temperature in mildly acidic media (473 K, pH 3.5). The obtained products were characterized as SAXS, XRD, N2 sorption, FTIR, TEM, NH3-TPD, AAS and ICP. The results show that the initial Si/Al molar ratio of ZSM-5 precursors strongly affects the final materials’ properties. A highly condensed, well-ordered mesoporous SBA-15 analog with improved hydrothermal stability and acidic properties can be prepared from low aluminum containing ZSM-5 precursors (Si/Al ≥ 20). Reducing the initial Si/Al molar ratio to 10, however, leads to the formation of a disordered mesoporous SBA-15 type material accompanied by degraded textural and acidic properties. The gas phase cracking of cumene, carried out as probe reaction to evaluate Brønsted acidity, reveals that an increased density of Brønsted acid sites has been achieved over the SBA-15 analogs compared to conventional Al-SBA-15 due to the preservation of zeolite building units in the mesopore walls of the SBA-15 analogs.
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MDPI and ACS Style
Vu, X.H.; Eckelt, R.; Armbruster, U.; Martin, A. High-Temperature Synthesis of Ordered Mesoporous Aluminosilicates from ZSM-5 Nanoseeds with Improved Acidic Properties. Nanomaterials 2014, 4, 712-725. https://doi.org/10.3390/nano4030712
AMA Style
Vu XH, Eckelt R, Armbruster U, Martin A. High-Temperature Synthesis of Ordered Mesoporous Aluminosilicates from ZSM-5 Nanoseeds with Improved Acidic Properties. Nanomaterials. 2014; 4(3):712-725. https://doi.org/10.3390/nano4030712
Chicago/Turabian StyleVu, Xuan H.; Eckelt, Reinhard; Armbruster, Udo; Martin, Andreas. 2014. "High-Temperature Synthesis of Ordered Mesoporous Aluminosilicates from ZSM-5 Nanoseeds with Improved Acidic Properties" Nanomaterials 4, no. 3: 712-725. https://doi.org/10.3390/nano4030712
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