C-12-RBS INVESTIGATION OF SCOLECITE CRYSTALS INTERACTED WITH CS-AQUEOUS AND SR-AQUEOUS SOLUTIONS

Crystals of the natural fibrous zeolite scolecite were exposed to cesi um and strontium aqueous solutions at room temperature. The reacted mi neral crystals were investigated by means of C-12-RBS using the 4.5 MV Tandem accelerator of the NRCPS ''Demokritos''/GR. The C-12-RBS spect ra indicated an inhomogeneous depth distribution of the sorbed element s on the scolecite and particular a remarkable metal accumulation in t he near-surface layers of the material. This phenomenon is more intens e in the case of strontium assigned to its bulkier hydrated cations an d the structural characteristics of the zeolite. The results of this w ork can contribute to the understanding of problems related to the tre atment of nuclear wastes using zeolitic materials and to their disposa l in zeolite-containing geologic formations. (C) 1998 Elsevier Science B.V.