Uranium(VI) separation from aqueous solution by calix[6]arene modified textiles

The separation of uranium(VI) from aqueous solution by textile bound uranophile calix[6]arenes is possible at pH values greater than or equal to4. A maximum of 7.6.10(-7) Mol uranium per 1 g of the calixarene modified textile is bound at pH 5. The influence of competing ions on the uranium separation at pH 5 is very small. However, at pH 7 in carbonate rich waters calcium ions have a competing effect. Under environmentally relevant pH conditions the uranium is strongly bound to the calixarene modified textile. Under acidic conditions an almost complete regeneration of the calixarene modified textile is possible. The regenerated material can be utilized for further uranium separation cycles.