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Acid activation of a Spanish sepiolite: II. Consideration of kinetics and physico-chemical modifications generated

Published online by Cambridge University Press:  09 July 2018

M.A. Vicente Rodriguez ,
J.D. Lopez Gonzalez ,
M.A. Bañares Muñoz  and
J. Casado Linarejos
M.A. Vicente Rodriguez
Affiliation:
Departamento de Química Inorgánica, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Senda del Rey s/n, 28040 Madrid Departamento de Química Inorgánica, Facultad de Química, Universidad de Salamanca, Plaza de los Caídos s/n, 37008 Salamanca
J.D. Lopez Gonzalez
Affiliation:
Departamento de Química Inorgánica, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Senda del Rey s/n, 28040 Madrid
M.A. Bañares Muñoz
Affiliation:
Departamento de Química Inorgánica, Facultad de Química, Universidad de Salamanca, Plaza de los Caídos s/n, 37008 Salamanca
J. Casado Linarejos
Affiliation:
Departamento de Química Física, Facultad de Química, Universidad de Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain
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Abstract

Sepiolite from Vallecas (Spain) was treated with HCl solutions (1.25; 2.5; 5.0; 10.0 and 20.0 wt%) at 25°C for 2, 6, 24 and 48 h. The solutions obtained after washing the acid treated samples were analysed and a kinetic model was applied to the cation dissolution data. The development of porosity and number of acid centres was studied. The experimental conditions which yield products with the highest surface activity were established. The size of the silica fibres, obtained after the treatment, decreases when the intensity of the treatments is increased. These characteristics are important for the adsorptive properties and the catalytic potential of a solid.

Type
Research Article
Information
Clay Minerals , Volume 30 , Issue 4 , December 1995 , pp. 315 - 323
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1995

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