High selectivity in anion exchange reactions of the anionic clay, cobalt hydroxynitrate

The selective uptake of fluoride ions from a mixture of halide ions and the selective uptake of chloride ions from a mixture of chloride, bromide and iodide ions were observed in the competitive anion exchange reactions of cobalt hydroxynitrate. In the case of divalent anions, the selective uptake of carbonate ions from a mixture of carbonate, oxalate and sulfate ions and the selective uptake of oxalate ions from a mixture of oxalate and sulfate ions were observed.