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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
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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

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