COMPLEXATION PROPERTIES OF THE CHELATING RESIN FUNCTIONALIZED WITH IMINODIACETIC ACID - APPLICATION TO COLUMN SEPARATION OF MOLYBDENUM AND TUNGSTEN

A chelating polymer resin having iminodiacetic acid (IDA) as the functional group has been prepared for the selective adsorption of oxo-molybdenum(VI) or oxo-tungsten(VI). The C-13- and H-1-NMR spectra of these IDA complexes have been studied in the pH range of 4-7 to elucidate the complexation properties of the functional group. The NMR study in the homogeneous system suggests that the IDA forms a 1:1 complex with Mo-VI and W-VI in the pH region 4-7. The peak integration of coordinated acetate signals indicates that the complex formation of IDA is much favorable with Mo-VI than with W-VI. A selective adsorption of Mo-VI over W-VI has been realized by the chelating resin having an IDA group. A mutual separation of Mo-VI and W-VI has been demonstrated by the IDA resin in a column system.