Effect of Zr(IV) to phosphorus ratio on U(VI) adsorption by diethylenetriamine-pentamethylene phosphate Zr(IV) hybrids

In this work, diethylenetriamine pentamethylenephosphonic acid (DTPMP) was ultilized into preparing of Zr(IV) organophosphates hybrids (Zr-DTPMP- x , x  was the molar ratio of Zr(IV)/DTPMP in the synthetic process, x  = 0.5, 1, 2, and 3) using a hydrothermal method. The physical and chemical properties of Zr-DTPMP- x were characterized by SEM&EDS, FT-IR, XRD, Zeta potential, XPS, TGA and contact angle analysis. Moreover, the adsorptive performances of Zr-DTPMP- x for U(VI) were investigated. The adsorption results showed that the optimum molar ratio of Zr(IV) to phosphine, pH, equilibrium time, and dosage was 0.5, 4.0, 180 min, and 10 mg, respectively. Besides, the adsorption of U(VI) was in accordance with the pseudo-second-order kinetic model and Sips isothermal model. Moreover, the adsorption capacity determined by Sips isothermal model was 181.34 mg g −1 for Zr-DTPMP-0.5. Furthermore, the adsorptive selectivity of Zr-DTPMP-0.5 for U(VI) was superior than the others. Zr-DTPMP-0.5 may be a powerful candidate for diminishing the contamination of U(VI).