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Journals / Journal of the Turkish Chemical Society Section A: Chemistry / 2021 / Cilt: 8 - Sayı: 4

Surface Acidities of Bentonite, Sepiolite, and Synthetic Silica-Aluminas

Mehmet Kadir YURDAKOÇ
Hasibe BÖLÜK
Aylin ALTINIŞIK TAĞAÇ
Pages
1153–1164
Publication Date
2021-11-30
DOI
—
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

IR spectroscopy with pyridine as a probe molecule was still very useful for the estimation of the surface acidities of the silica-alumina and also aluminosilicate structures such as clays and clay minerals.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:The surface acidities of Bentonite, Sepiolite, and Silica-Aluminas were determined by Hammett indicators, amine titrations, and of pyridine adsorption-IR spectroscopy.
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Key Findings & Data:Lewis and total surface acidity values of sepiolite were higher than bentonite, 0.53 and 2.22 mmole g-1, respectively.
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Conclusion & Impact:IR spectroscopy with pyridine as a probe molecule was still very useful for the estimation of the surface acidities of the silica-alumina and also aluminosilicate structures such as clays and clay minerals.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:surface acidity · Hammett indicators · amine titration

Abstract

The surface acidities of Bentonite, Sepiolite, and Silica-Aluminas were determined by Hammett indicators, amine titrations, and of pyridine adsorption-IR spectroscopy. The quantitative estimation of surface acidities of silica-aluminas and their natures as Brønsted and Lewis acid sites were evaluated. Lewis and total surface acidity values of sepiolite were higher than bentonite, 0.53 and 2.22 mmole g-1, respectively. Surface acidity values of sepiolite and bentonite were much lower than Siral compounds. Among the Siral compounds, Siral 30 was found to be more effective in terms of acidity. All samples have both Lewis and Brønsted acid centers in which the Lewis sites predominated. IR spectroscopy with pyridine as a probe molecule was still very useful for the estimation of the surface acidities of the silica-alumina and also aluminosilicate structures such as clays and clay minerals.

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Cite This Article

YURDAKOÇ, M. K., BÖLÜK, H., TAĞAÇ, A. A. (2021). Surface Acidities of Bentonite, Sepiolite, and Synthetic Silica-Aluminas. Journal of the Turkish Chemical Society Section A: Chemistry, Cilt: 8 - Sayı: 4, 1153–1164. https://ajindex.com/articles/781088

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