Efficient separation and recovery of Re (VII) from Re/U bearing acidic solutions using aminotriazole modified cellulose microsphere adsorbents

Abstract

In this work, aminotriazole-modified microcrystalline cellulose microspheres (3-ATAR) containing an abundant nitrogen content as promising adsorbent was prepared via a radiation grafting method for the selective recovery ReO4- in the presence of UO22+ in acidic solution. A series of batch and column adsorption experiments including monocomponent and binary systems, were designed for evaluating the adsorption and separation performance of Re (VII) onto 3-ATAR. The 3-ATAR exhibited a good adsorption capacity (max 146.4 mg·g-1) of Re(VII) and a rapid adsorption rate, with equilibrium time of 45 min. In binary solution, the high selectivity coefficients (βRe/M) indicated that 3-ATAR could separate and recover Re(VII) from U(VI) and other metal ions (Cu(II), Cr(III), Ni(II), Zn(II)). In particular, it was found that the adsorption of Re was almost unaffected in U/Re-bearing solutions no matter how much the U(VI) was changed. In the column experiment, when the concentration of U(VI) was 40 times higher than that of Re(VII), 3-ATAR manifested high Re(VII) selectivity over U(VI) from a synthetic uranium ore leachate. This work demonstrated that 3-ATAR could provide an efficient, selectively, sustainable, and industrially feasible way for Re(VII) to be recovered from uranium ore leachate and other prospective sources.