Combustion treatment of Co2+ and Cs+ exchanged zeolites

The capacity of A, X and clinoptilolite zeolites to remove Co2+ or Cs+ is compared. The Co2+ and Cs+ exchanged zeolites were thermally and combustion treated until vitrification. Desorption of cobalt and cesium from those treated solids was tested by lixiviation with 1 N NaCl solution. As the calcining temperature increased, the cristallinity of cobalt and cesium exchanged zeolites decreased. The retention of cobalt and cesium in thermally treated exchanged zeolites is slightly higher than in combustion treated zeolites ignited at 1000 °C. The difference is attributed to the compounds (amorphous and crystalline) formed during the treatments. The cobalt and cesium content were determined by neutron activation analyses and the solids were characterized by X-ray diffraction, IR-spectroscopy and scanning electron microscopy (SEM).