ION-EXCHANGE PROPERTIES OF THE SODIUM PHLOGOPITE AND BIOTITE

The ion exchange behavior of three sodium micas (phlogopite, Ward's Sc i.; phlogopite, Suzorite Inc., biotite, Ward's Sci.) towards Li+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, Pb2+, Hg2+, Co-2+,Co- Cu2+, Cd2+ and Zn2+ ions has been studied. The ion exchange isotherms of alkali, alk aline earth and some other divalent cations were determined and concen tration equilibrium constants as a function of metal loading and tempe rature were analyzed. Sotlium micas exhibit high affinity for heavy al kali metals with the selectivity order Rb+ > Cs+ > K+. By studying the cesium uptake in the presence of NaNO3, CaCl2, NaOH, NaOH+KOH, HNO3 e lectrolytes (in the range of 0.01-6 (M) under bar) it was found that s odium micas could remove cesium efficiently in neutral and alkaline me dia, which make them promising for certain types of nuclear waste trea tment.