HDEHP-CMPO/SiO2-P: a promising solid-phase extractant for uranium recovery from different acidic media

A novel macroporous silica-based HDEHP-CMPO impregnated polymeric solid-phase extractant showed an excellent uranium adsorption efficiency from HNO3, HCl, and H2SO4 media with the wide concentration range from the near neutral to high acidic conditions. The adsorption equilibrium data were well described with the Redlich-Peterson isotherm with the relatively high uranium adsorption capacity. Furthermore, the HDEHP-CMPO/SiO2-P showed a significant selectivity for U(VI) among the coexisting elements while the co-extraction of Fe(III) with U(VI) was observed. In desorption process, Fe(III) and U(VI) were separated and desorbed efficiently using the 1 M H2SO4 solution at 55 A degrees C and 1 M NH4HCO3 solution at 25 A degrees C, respectively.