Fig. 1. Synthesis route of P-TETA-AO, P-TEPA-AO, and P-PEHA-AO

Fig. 2. Synthesis reaction formula of P-TETA, P-TEPA, and P-PEHA

Fig. 3. Synthesis reaction formula of P-TETA-AN, P-TEPA-AN, and P-PEHA-AN

Fig. 4. ATR-FTIR spectra of the material before and after modification

Fig. 5. SEM images of pristine PP/PE SNW, and P-TETA-AO, P-TEPA-AO, P-PEHA-AO before and after uranium absorption(a~g), image on color changes of three kinds of adsorption materials before and after uranium adsorption (h) (color onlinr)

Fig. 6. (a) TG and (b) DTG curves of pristine PP/PE SNW, P-TETA-AO-U, P-TEPA-AO-U, and P-PEHA-AO-U (color online)

Fig. 7. Diagrams of changes in water contact angle before and after modification of (a) P-TETA-AO, (b) P-TEPA-AO, and (c) P-PEHA-AO

Fig. 8. Effects of pH on uranium removal ratio of (a) P-TETA-AO, (b) P-TEPA-AO and (c) P-PEHA-AO

Fig. 9. Dependence of uranium removal ratio on time, pseudo-first-order and pseudo-second-order models kinetic fitting for (a~c) P-TETA-AO, (d~f) P-TEPA-AO, (g~i) P-PEHA-AO

Fig. 10. Adsorption properties of (a~b) P-TETA-AO, (c~d) P-TEPA-AO, (e~f) P-PEHA-AO affected by the initial concentration of uranium and adsorption isotherm.

Fig. 11. Langmuir and Freundlich isotherms models of (a~b) P-TETA-AO, (c~d) P-TEPA-AO, (e~f) P-PEHA-AO

Fig. 12. Uranium removal ratio of P-TETA-AO, P-TEPA-AO, and P-PEHA-AO in simulated seawater.

Fig. 13. Adsorption-desorption efficiency of (a) P-TETA-AO, (b)P-TEPA-AO, and (c) P-PEHA-AO for uranium

Fig. 14. ATR-FTIR spectra of (a) P-TETA-AO, (b) P-TEPA-AO, and (c) P-PEHA-AO before and after uranium adsorption

Fig. 15. (a) XPS spectra of three materials before and after uranium adsorption; (b) U4f spectra after uranium adsorption;(c~k) spectra of various elements before and after uranium adsorption