Cation-Exchange Behavior of Clays and Synthetic Aluminosilica Gels1

C. H. Chu and L. J. Johnson
Department of Agronomy, The Pennsylvania State University University Park, Pennsylvania 16802
1 Authorized for publication as Paper No. 5512 in the journal series of the Agricultural Experimental Station, The Pennsylvania State University.

Abstract: Cation-exchange capacities determined by methylene blue adsorption (CEC MB) and by the amount of K displaced from a K-saturated clay by NH4 (CEC K//NH4) correlate closely in five soil clays from Pennsylvania, but differ greatly in two soil clays with a large content of amorphous material. CEC MB was found to provide a more precise distinction between montmorillonite and vermiculite than CEC K//NH4. Synthetic aluminosilicate gels showed CEC K//NH4 > CEC Ca/Mg > CEC MB, but no relation to the behavior of the two soil clays with a large content of amorphous material was found.

Key Words: Amorphous Material • Ca/Mg • K//NH4 • Methylene Blue • Montmorillonite • Vermiculite

Clays and Clay Minerals; April 1979 v. 27; no. 2; p. 87-90; DOI: 10.1346/CCMN.1979.0270202
© 1979, The Clay Minerals Society
Clay Minerals Society (www.clays.org)