Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays
Pillared clays are interesting materials with applications in catalysis and adsorption processes. To obtain these materials, several preparation procedures are necessary and must be optimized to tune the final properties of the resulting pillared clay. Therefore, this article reports the influence o...
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MDPI AG
2021-10-01
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| Series: | Minerals |
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| Online Access: | https://www.mdpi.com/2075-163X/11/11/1211 |
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| author | Anderson Parodia Janaina A. Prasniski Francine Bertella Sibele B. C. Pergher |
| author_facet | Anderson Parodia Janaina A. Prasniski Francine Bertella Sibele B. C. Pergher |
| author_sort | Anderson Parodia |
| collection | DOAJ |
| description | Pillared clays are interesting materials with applications in catalysis and adsorption processes. To obtain these materials, several preparation procedures are necessary and must be optimized to tune the final properties of the resulting pillared clay. Therefore, this article reports the influence of synthesis parameters (temperature and concentration) of Keggin-Al<sub>13</sub> polycations and different intercalation times (0.5 up to 72 h) on the structural properties of Al-pillared clays. The natural clays are from Brazil, and they are composed mainly of montmorillonite. By XRD, N<sub>2</sub> sorption, XRF and <sup>27</sup>Al NMR results of the Al-PILCs, we verified that the pillaring solution could be prepared at room temperature with an aging time of 24 h. For the cation exchange process, a period of at least 2 h is necessary to ensure the formation of pillared materials. The concentration of the Keggin-Al<sub>13</sub> polycations was evaluated by using diluted pillaring solutions followed by applying re-pillaring procedures. After submitting the pillared clay to another pillaring process, the number of pillars in the interlamellar space increased; however, the micropore volume decreased concomitantly. Thus, by optimizing the synthesis conditions of the Keggin-Al<sub>13</sub> polycations, Al-PILCs could be obtained with good values of basal spacing and specific surface area. |
| first_indexed | 2024-03-10T05:15:04Z |
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| id | doaj.art-bd060bb926e640b296ddf8159277483b |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-10T05:15:04Z |
| publishDate | 2021-10-01 |
| publisher | MDPI AG |
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| series | Minerals |
| spelling | doaj.art-bd060bb926e640b296ddf8159277483b2023-11-23T00:31:56ZengMDPI AGMinerals2075-163X2021-10-011111121110.3390/min11111211Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared ClaysAnderson Parodia0Janaina A. Prasniski1Francine Bertella2Sibele B. C. Pergher3Molecular Sieves Laboratory (Labpemol), Federal University of Rio Grande do Norte—UFRN, Av. Senador Salgado Filho, 3000, Natal 59078-970, BrazilMolecular Sieves Laboratory (Labpemol), Federal University of Rio Grande do Norte—UFRN, Av. Senador Salgado Filho, 3000, Natal 59078-970, BrazilLaboratório de Reatividade e Catálise (LRC), Universidade Federal do Rio Grande do Sul, CP 15003, Porto Alegre 91501-970, BrazilMolecular Sieves Laboratory (Labpemol), Federal University of Rio Grande do Norte—UFRN, Av. Senador Salgado Filho, 3000, Natal 59078-970, BrazilPillared clays are interesting materials with applications in catalysis and adsorption processes. To obtain these materials, several preparation procedures are necessary and must be optimized to tune the final properties of the resulting pillared clay. Therefore, this article reports the influence of synthesis parameters (temperature and concentration) of Keggin-Al<sub>13</sub> polycations and different intercalation times (0.5 up to 72 h) on the structural properties of Al-pillared clays. The natural clays are from Brazil, and they are composed mainly of montmorillonite. By XRD, N<sub>2</sub> sorption, XRF and <sup>27</sup>Al NMR results of the Al-PILCs, we verified that the pillaring solution could be prepared at room temperature with an aging time of 24 h. For the cation exchange process, a period of at least 2 h is necessary to ensure the formation of pillared materials. The concentration of the Keggin-Al<sub>13</sub> polycations was evaluated by using diluted pillaring solutions followed by applying re-pillaring procedures. After submitting the pillared clay to another pillaring process, the number of pillars in the interlamellar space increased; however, the micropore volume decreased concomitantly. Thus, by optimizing the synthesis conditions of the Keggin-Al<sub>13</sub> polycations, Al-PILCs could be obtained with good values of basal spacing and specific surface area.https://www.mdpi.com/2075-163X/11/11/1211pillared claysAl-PILCKeggin-Al<sub>13</sub> polycationssynthesis parameterstemperatureintercalation time |
| spellingShingle | Anderson Parodia Janaina A. Prasniski Francine Bertella Sibele B. C. Pergher Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays Minerals pillared clays Al-PILC Keggin-Al<sub>13</sub> polycations synthesis parameters temperature intercalation time |
| title | Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays |
| title_full | Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays |
| title_fullStr | Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays |
| title_full_unstemmed | Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays |
| title_short | Keggin-Al<sub>13</sub> Polycations: Influence of Synthesis and Intercalation Parameters on the Structural Properties of Al-Pillared Clays |
| title_sort | keggin al sub 13 sub polycations influence of synthesis and intercalation parameters on the structural properties of al pillared clays |
| topic | pillared clays Al-PILC Keggin-Al<sub>13</sub> polycations synthesis parameters temperature intercalation time |
| url | https://www.mdpi.com/2075-163X/11/11/1211 |
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