Comparison of Cation Exchange in Ganophyllite and [Na + Al]-Substituted Tobermorite: Crystal-Chemical Implications

Sridhar Komarneni and Stephen Guggenheim
Materials Research Laboratory and Department of Agronomy, The Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A.
Department of Geological Sciences, University of Illinois at Chicago, Chicago, Illinois 60680, U.S.A.

Abstract: Ganophyllite and [Na+ + Al3+]-substituted tobermorite exhibited similar cation exchange properties and, in particular, selective cesium exchange. [Na+ + Al3+]-substituted tobermorite and ganophyllite showed a selective Cs exchange of 10.77 and 8.71 meq/100 g from 0.02N NaCl and of 11.08 and 9.04 meq/100 g from 0.02N CaCl2, respectively. The [Na+ + Al3+]-substituted tobermorite is structurally similar to ganophyllite: both are roughly analogous to 2:1 layer silicates, both have cross-linking tetrahedra across the interlayer region, and both have exchangeable cations located in zeolite-like sites in the interlayer region. The similarities in cation exchange properties imply that the residual charge configuration of the analogue 2 : 1 layer must be approximately equivalent also.

Keywords: ganophyllite • tobermorite • cation exchange

Mineralogical Magazine; June 1988 v. 52; no. 366; p. 371-375; DOI: 10.1180/minmag.1988.052.366.08
© 1988, The Mineralogical Society
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