The Effect of Cation Exchange of Tris(Ethylenediamine)Cobalt(III) for Sodium on Nitrogen Sorption by Montmorillonite

Abstract

The cation exchange process between tris(ethylenediamine)cobalt(llI) and Na + on mont- moriUonite was studied by atomic absorption spectrophotometry, X-ray diffraction, differential thermal analysis, and nitrogen sorption at 78~ The exchange of Co(en)33+ for Na § was found to be extremely favorable, with a tendency toward segregation of the two kinds of cations in the mixed clays studied. Small amounts of Co(en)a § were found to lower the nitrogen sorption capacity of Na § mont- morillonite while clays with high Co(en)3 +a content had greatly enhanced sorption. An explanation is offered in terms of a dual role of the Co(en)3 +~ in determining the kind and amount of nitrogen sorption in the exchanged montmorillonite.