Highly efficient adsorptive removal of uranyl ions from aqueous solutions using dicalcium phosphate nanoparticles as a superabsorbent

• Published in: Nuclear engineering and technology Vol. 50; no. 7; pp. 1112 - 1119
• Main Authors: Saghatchi, Hadis, Ansari, Reza, Mousavi, H. Zavvar
• Format: Journal Article
• Language: Korean
• Published: 2018
• Subjects: Nanoparticles; Adsorption; Monetite; Adsorption isotherm; Uranium (VI)
• ISSN: 1738-5733; 2234-358X

Dicalcium phosphate nanoparticles (DCP-NPs) was synthesized chemically and used for adsorptive removal of uranyl ions from aqueous solutions in a batch system. A commercial grade of DCP (monetite) was also employed for comparison. The synthesized and commercial adsorbents (S-DCP and C-DCP) were characterized by FT-IR, SEM and XRD techniques. The investigation of adsorption isotherms indicated that the maximum adsorption capacities ($q_m$) for C-DCP and S-DCP were 714.3 and $666.7mg\;g^{-1}$ (at 293 K), respectively. The experimental kinetics were well-described by the pseudo-second-order kinetic and the equilibrium data were fitted with both Langmuir and Freundlich adsorption models. Thermodynamic studies indicated that the adsorption of uranyl ions on the monetite surface was a spontaneous exothermic process. The exhausted adsorbents could be regenerated by washing with $0.10mol\;L^{-1}$ NaOH.