Synthesis of TOPO/XAD-16 impregnated resins and effective adsorption of uranium (VI) in acidic solution

In this study, TOPO/XAD-16 solvent impregnated resins (TOPO/XAD-16) were prepared by wet impregnation and the best impregnation conditions were determined by orthogonal experiment. SIRs were characterized by SEM, FTIR and BET, and the influencing factors were also investigated about U(VI) adsorption on SIRs, such as contact time, solid–liquid ratio, pH and ionic strength. The results showed that adsorption data can be well fitted by pseudo-second-order kinetic model and Langmuir model. Meanwhile, the adsorption process was multistep kinetics controlled by chemisorption and intraparticle diffusion model. Adsorbed U(VI) ions on SIRs and CSIRs (coated solvent impregnated resins) were desorbed effectively using 1.0 mol/L NH 4 HCO 3 . After 6 cycles, the adsorption rate of CSIRs is still more than 90%, which manifested CSIRs prepared can really improve the stability of SIRs. Therefore, CSIRs has good reusability, and has great potential to extract uranium from acidic uranium wastewater.