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Properties and Catalytic Activity of Acid-Modified Montmorillonite and Vermiculite

Published online by Cambridge University Press:  28 February 2024

J. Ravichandran  and
B. Sivasankar
J. Ravichandran
Affiliation:
Department of Chemical Engineering, Anna University, Madras - 600 025, India
B. Sivasankar
Affiliation:
Department of Chemistry, Anna University, Madras - 600 025, India
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Abstract

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The acidic properties of acid-modified montmorillonite and vermiculite were determined by pyridine and ammonia adsorption to correlate with the alkylating and dehydrating activity of the activated samples. Treatment of the minerals with different concentrations of hydrochloric acid results in the variation of overall acidity and density of acidic sites. Infrared (IR) spectral and differential scanning calorimetric analyses have revealed the presence of Bronsted and Lewis acid sites on the activated samples. The catalytic activity towards the above reaction has been correlated to the acid strength and density of Lewis acid sites. Treatment of montmorillonite with hydrochloric acid in the range of 0.1 and 0.3 M and vermiculite with 0.2 to 0.3 M seemed to be suitable for the conversion of methanol into olefin-rich hydrocarbons. Acid-activated montmorillonite catalyzed the isopropylation of benzene to a maximum extent of 16%, whereas acid-activated vermiculite gave a maximum conversion of only 4%.

Keywords

AcidityBenzeneCatalyst CharacterizationHydrocarbonsIsopropylationMethanol DehydrationMontmorilloniteVermiculite
Type
Research Article
Information
Clays and Clay Minerals , Volume 45 , Issue 6 , December 1997 , pp. 854 - 858
Copyright
Copyright © 1997, The Clay Minerals Society

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