SELECTIVE STRONTIUM REMOVAL FROM A SODIUM-NITRATE AQUEOUS-MEDIUM BY NANOFILTRATION-COMPLEXATION

In aqueous medium, selective complexation increases the ionic separati on by nanofiltration. The combination of nanofiltration and complexati on can be applied to the nuclear effluents treatment. To separate radi oelements from a sodium salt medium, poly(acrylic acid) is associated to the FILMTEC NF 70 membrane. Effects of transmembrane pressure, pH, ligand concentration and ionic strength on salts retention are describ ed, and the complexation constants are estimated. Finally, to reach th e objectives, a strontium two - stages concentration by nanofiltration - complexation with a control of retentate salinity is investigated i n a nonactive solution case.