Design of a solar reactor for the removal of uranium from simulated nuclear wastewater with oil-apatite ELM system
Ali Aghababai Beni
Abstract
Nuclear wastewater containing uranium ions is a serious threat to the environment. In this study, uranium (VI) ions were adsorbed from the synthesized wastewater by hydroxyapatite nanoparticles (NHAP) in the emulsion liquid membrane (ELM) process. The NHAP was dispersed in the oil, and ELM globules were formed by injecting the NHAP-oil phase into the wastewater. The FT-IR of NHAP, before and after separation process showed the hydroxyl, amine, and phosphoryl groups are important to immobilization of U(VI) ions in oil phase. The morphology of NHAP was identified with FE-SEM, with the NHAP size intially 50 nm, while and at the end the size was about 1 μm. The following optimum conditions were selected: pH = 4, NHAP concentration = 12.4 gL-1, volume of ELM = 43 ml, retention time = 45 min, air flow rate = 0.5 Lmin-1 and impeller rotation speed = 200 rpm. The viscosity of the oil phase decreased with solar radiation and the U(VI) adsorption on the NHAP surface was improved. The oil and air phase distribution within the water phase was simulated. Adsorption isotherms, thermodynamic parameters and kinetic data were investigated.