On selective properties of transition metal ferrocyanides

Selective properties of cobalt (2) normal ferrocyanide as to the ions of alkali metals and ammonium have been studied. Exchange of potassium-, rubidium-, cesium- and ammonium ions on the sorbent salt forms is investigated. The characteristic of the crystal structure is obtained, spectral characteristics of the compoUnds in the IR region are presented, reaction of isotopic exchange is studied. A model of alkali metal- and ammonium ions sorption is developed. It is shown that the sorbent selective properties, as to the ions of heavy alkali metals (rUbidium and cesium) are determined by their participation in the formation of donor-acceptor bond according to the dsub(π)-dative interaction with hexacyanferrate-ions in solid phase. A conclusion is draWn on a predominant role of chemical interaction in the process of alkali metal and ammonium ion sorption on transition metal ferrocyanides