Synthesis and properties of a cellulose exchanger with the crown ether diaminodibenzo-17-crown-5 as anchor group

A new cellulose exchanger was synthesized from “o-aminophenolcellulose” by diazotation and coupling with diaminodibenzo-17-crown-5. The distribution coefficients for Ca²⁺, Sr²⁺, Ba²⁺, Na⁺ and K⁺ were determined in water/methanol mixtures as a function of the water content. Separation of Ca²⁺, Na⁺ and K⁺ and fractionation of the calcium isotopes ⁴⁸Ca and ⁴⁰Ca were investigated. The enrichment factor ε = 4.9 · 10^?3 for ⁴⁸Ca²⁺ is appreciably higher than that found for cation exchange resins with ? SO₃H groups, but lower than that reported for certain cryptands.