Highly efficient adsorption of uranyl ions using hydroxamic acid-functionalized graphene oxide

Abstract A chelating matrix prepared by immobilizing N-hydroxyl amine onto graphene oxide functionalized with aspartic acid (GO-HDX) was applied to recover UO 2 2+ from their SO 4 2− leach liquor. SEM-EDAX, FT-IR, TGA, and XRD instruments, in addition, Raman spectroscopy (IR-Raman), were used to analyze the synthesized GO-HDX. The static extraction technique optimized various physicochemical parameters that impacted the UO 2 2+ extraction. The optimal pH, time of contact, initial concentration, GO-HDX dose, temp., foreign ions, and eluting agents were gained. The experimental equilibrium documents were assessed using Langmuir and Freundlich equations. The Langmuir equation model quite fits the investigational adsorption data with a maximum uptake of 277.78 mg/g, and it implied the attending of monolayer coverage of adsorbed molecules. Pseudo-first- and pseudo-second-order analyses were done to inspect the kinetic results. The data indicated that pseudo-second-order kinetics fit all concentrations. The intended thermodynamic factors were ∆G° negative values and ∆H° positive value. The data signified that the UO 2 2+ extraction onto GO-HDX was spontaneous adsorption and endothermic at higher temperatures. The regeneration efficiency of GO-HDX was 98% using 1 M HCl.