Ion-exchange in chabazite

Several near homoionic forms of a purified natural chabazite from Bowie, Arizona have been prepared. Ion-exchange isotherms have been measured for the uptake of caesium and strontium onto each of the forms of chabazite using radiochemical methods. Selectivity series were constructed based on free energies of exchange (Delta G degrees) calculated from Kielland plots derived from the isotherms. Values of Delta H degrees and Delta S degrees were also derived. Comparisons are made to other literature values of these thermodynamic functions. Comments are made on the potential use of the natural chabazite in the treatment of aqueous nuclear waste. (C) 1998 Elsevier Science B.V. All rights reserved.