Sorption of radioactive cobalt in natural Mexican clinoptilolite

Abstract

The ability of a natural Mexican clinoptilolite to sorb radioactive cobalt from aqueous solution was studied. The zeolite was stabilized partially with sodium and the content of Na⁺ in the samples was determined by neutron activation analysis. Ion exchange experiments were performed with solution labeled with radioactive⁶⁰Co at pH 6.5. XRD patterns were used to verify if the crystallinity of the aluminosilicate was affected by ionic exchange. A fast sorption uptake was observed and it was found that 0.408 meq/g of zeolite of Na⁺ ions were replaced by cobalt ions, followed by a desorption process where the uptake decrease to 0.314 meq/g of zeolite. This behavior is a consequence of the partial dehydration of the zeolite.