Vitrification of gamma irradiated 60Co2+ zeolites

A and X Go-exchanged zeolites were thermally treated until vitrification and, then, gamma irradiated. Desorption of cobalt from those treated solids was verified by ion exchange with 1N NaCl solution. As the calcining temperature increased, the crystallinity of cobalt exchanged zeolites decreased. At high temperatures (1000 degreesC), the vitrification was an intermediate state as the amorphous compounds recrystallized in the form of nepheline. The irradiation induced small changes in the cell parameters. In X zeolite, irradiation treatment diminished the vitrification temperature. The vitrifred samples, whether irradiated or not, safely trapped the cobalt originally present in the zeolites. The solids were characterized by X-ray diffraction, IR-spectroscopy and the cobalt content was determined by neutron activation analyses. (C) 2001 Elsevier Science B.V. All rights reserved.