Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-23T16:14:10.530Z Has data issue: false hasContentIssue false

Dissolution kinetics of sepiolite from Eskisehir (Turkey) in hydrochloric and nitric acids

Published online by Cambridge University Press:  09 July 2018

H. Cetisli
Affiliation:
Anadolu University, Engineering and Architectural Faculty, Chemical Engineering Department, Eskisehir, Turkey
T. Gedikbey
Affiliation:
Anadolu University, Engineering and Architectural Faculty, Chemical Engineering Department, Eskisehir, Turkey

Abstract

Dissolution kinetics of sepiolite from Eskisehir (Turkey) have been investigated at various temperatures and particle sizes using dilute hydrochloric and nitric acids. Dissolution reaction rate constants were calculated and apparent activation energies were dependent on acid concentration. For both acids, apparent activation energy values reached a minimum of ∼11 kcal/mol at an acid concentration of 0·75 M. For the second-order reaction which is independent of the acid concentration, the activation energy was 14·5 kcal/mol for both acids. The reaction rate constants were proportional to the acid concentrations, and inversely proportional to the square-root of the initial particle radii of the sepiolite.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abdul-Latif, N. & Weaver, E.C. (1969) Kinetics of dissolution of palygorskite (attapulgite) and sepiolite. Clays Clay Miner., 17, 169–178.Google Scholar
Acosta, J.L., Rocha, C.M. & Ojeda, M.C. (1984) The effect of several modified sepiolites on the transition temperatures and crystallinity of filled polypropylene. D. Angew. Makromol. Chemie, 126, 51–57.Google Scholar
Bonilla, J.L., Lopez-Gonzalez, J.D., Ramirez-Saenz, A., Rodriguez-Reinoso, F. & Valenzuela-Calahorro, C. (1981) Activation of a sepiolite with dilute solutions of HN03 and subsequent heat treatment: II. Determination of surface acid centres. Clay Miner., 16, 173–179.Google Scholar
Cetisli, H. (1988) The Surface Acid-Base and Sorption Properties of Sepiolite from Eskisehir, Turkey. TUBITAK, MAG-704, Ankara.Google Scholar
Cetisli, H. (1989) The surface acid-base properties of sepiolite from Eskisehir. DOGA, Turk. J. Eng. Envir. Sci., 13, 213–228.Google Scholar
Corma, A., Perez-Pariente, J., Fornes, V. & Mifsud, A. (1984) Surface acidity and catalytic activity of a modified sepiolite. Clay Miner,, 19, 673–676.Google Scholar
Corma, A., Mifsud, A. & Perez, J. (1986) Etude cinetique de Tattaque acide de la sepiolite: Modifications des proprietes texturales. Clay Miner., 31, 69–84.Google Scholar
Corma, A. & Perez-Pariente, J. (1987) Catalytic activity of modified silicates: I. Dehydration of ethanol catalysed by acidic sepiolite. Clay Miner., 22, 423–433.Google Scholar
Dandy, A.J. & Nadiye-Tabbiruka, M.S. (1982) Surface properties of sepiolite from Amboseli, Tanzania, and its catalytic activity for ethanol decomposition. Clays Clay Miner., 30, 347–352.Google Scholar
Gonzalez Hernandez, L., Ibarra, Rueda L. & Rodriguez, Dias A. (1982) Preparation of silica by acid dissolution of sepiolite and study of its reinforcing effect in elastomers. D. Angew. Makromol. Chemie, 103, 51–60.Google Scholar
Gonzalez, L., Ibarra, L.M., Rodriguez, A., Moya, J.S. & Valle, F.J. Fibrous silica gel obtained from sepiolite by HC1 attack. Clay Miner., 19, 93–98.Google Scholar
Gulensoy, H. (1984) Kompleksometrinin Esaslari ve Kompleksometrik Titrasyonlar pp. 152158. Fatih Ya., Istanbul.Google Scholar
Jimenez-Lopez, J., Lopez-Gonzalez, J.D., RamireZ-Saenz, A., Rodriguez-Reinoso, F., Valenzuela-Calahorro, C. & Zurita-Herrera, L. (1978) Evaluation of surface area in a sepiolite as a function of acid and heat treatment. Clay Miner., 13, 375–385.Google Scholar
Rodriguez-Reinoso, F., Ramirez-Saenz, A., Lopez-Gonzalez, J.D., Valenzuela-Calahorro, C. & Zurita-Herrera, L. (1981) Activation of sepiolite with dilute solutions of HNO3 and subsequent heat treatment: III. Development of porosity. Clay Miner., 16, 315–323.Google Scholar
Satterfied, C.N. (1980) Rates and kinetics models of catalytic reactions. Pp. 4267 in: Heterogen Catalysts in Practice. McGraw-Hill Book Co., New York.Google Scholar
Shimosaka, K., Kawano, M. & Taniguchi, T. (1973) Effect of acid treatment for sepiolite. J. Clay Sci. Soc. Japan, 13, 113–122.Google Scholar
Wadworth, M.E. & Miller, J.D. (1979) Hydrometallurgical processes. Pp. 133197 in: Rate Processes of Extractive Metallurgy. (H.Y. Sohn & M.E. Wadworth, editors). Plenum Press, New York.Google Scholar