Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-29T14:14:29.505Z Has data issue: false hasContentIssue false
  • English
  • Français

Characterization of smectites synthesised from zeolites and mechanism of smectite synthesis

Published online by Cambridge University Press:  09 July 2018

S. Komarneni  and
E. Breval
S. Komarneni
Affiliation:
Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802, USA
E. Breval
Affiliation:
Materials Research Laboratory, The Pennsylvania State University, University Park, PA 16802, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Smectites were synthesised hydrothermally from zeolites in an Mg-rich brine at 300°C under a confining pressure of 30 MPa and characterized by XRD using the Greene-Kelley Li-saturation test and the K+-saturation/glycolation test. The synthetic smectites were found to be dioctahedral with only tetrahedral negative layer charge; the layer charge was also deduced to be low and they are classified as beidellites. The mechanism of formation includes H+ saturation of zeolites by the hydrolysis of Mg2+ under hydrothermal conditions, followed by decomposition of the zeolites and recrystallization to beidellites. These results show that solution chemistry is an important factor affecting stability of zeolites under hydrothermal conditions.

Type
Research Article
Information
Clay Minerals , Volume 20 , Issue 2 , June 1985 , pp. 181 - 188
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1985

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

Braithwaite, J.W. & Molecke, M.A. (1980) Nuclear waste canister corrosion studies pertinent to geologic isolation. Nucl. Chem. Waste Management 1, 37–50.Google Scholar
Brindley, G.W. & Brown, G. (1980) Crystal Structures of Clay Minerals and their X-ray Identification, pp. 170 and 328. Mineralogical Society, London.Google Scholar
Greene-Kelley, R. (1955) Dehydration of the montmorillonite minerals. Mineral. Mag. 30, 604–615.Google Scholar
Grim, R.E. (1968) Clay Mineralogy, p. 86. McGraw-Hill Book Company, New York.Google Scholar
Grim, R.E. & Guven, N. (1978) Bentonites; Geology, Mineralogy, Properties and Uses, p. 21. Elsevier, Amsterdam.Google Scholar
Hofmann, U. & Klemen, E. (1950) Loss of exchangeability of lithium ions in bentonite on heating. Z. anorg. allg. Chem. 262, 95–99.Google Scholar
Jackson, M.L. (1969) Soil Chemical Analysis—Advanced Course, p. 187. Published by the author, Department of Soil Science, University of Wisconsin, Madison, WI 53706.Google Scholar
Komarneni, S. (1981) Hydrothermal stability of β-Cs2U2O7 and SrZrO3 in fluids. J. Inorg. NucL Chem. 43, 2833–2837.Google Scholar
Komarneni, S., Freeborn, W.P. & Smith, C.A. (1979) Simple cold-weld sealing of noble metal tubes, Am. Miner. 64, 650–651.Google Scholar
Komarneni, S. & Roy, D.M. (1983) Alteration of clay minerals and zeolites in hydrothermal brines. Clays Clay Miner. 31, 383–391.Google Scholar
Schultz, L.G. (1969) Lithium and potassium absorption, dehydroxylation temperature, and structural water content of aluminous smectites. Clays Clay Miner. 17, 115–149.Google Scholar