Selective extraction of U(VI), Th(IV), and La(III) from acidic matrix solutions and environmental samples using chemically modified Amberlite XAD-16 resin

A new grafted polymer has been developed by the chemical modification of Amberlite XAD-16 (AXAD-16) polymeric matrix with [(2-dihydroxyarsinoylphenylamino)methyl]phosphonic acid (AXAD-16-AsP). The modified polymer was characterized by a combination of (13)C CPMAS and (31)P solid-state NMR, Fourier transform-NIR-FIR-Raman spectroscopy, CHNPS elemental analysis, and thermogravimetric analysis (TGA). The distribution studies for the extraction of U(VI), Th(IV), and La(III) from acidic solutions were performed using an AXAD-16-AsP-packed chromatographic column. The influences of various physiochemical parameters on analyte recovery were optimized by both static and dynamic methods. Accordingly, even under high acidities (>4 M), good distribution ratio (D) values (10(2)-10(4)) were achieved for all the analytes. Metal ion desorption was effective using 1 mol L(-1) (NH(4))(2)CO(3). From kinetic studies, a time duration of