Efficient adsorption of ^152+154Eu(III) by surfactant modified mg/al layered double hydroxide

The remediation of radioactive liquid waste, particularly those containing complexing ligands, remains a critical environmental challenge. In this study, magnesium-aluminum layered double hydroxides (Mg/Al-LDHs) were modified via a one-pot synthesis using cetyltrimethylammonium bromide (CTAB) to enhance their adsorption performance toward Eu-EDTA anionic complexes, a model radionuclide contaminant. The modified LDH materials were characterized by FT-IR, XRD, SEM, and TGA/DTA to assess their structural, morphological, and thermal properties. Adsorption experiments revealed that 90 % of Eu-EDTA was removed within 60 min, reaching equilibrium after 180 min. The adsorption capacity increased by 50 % post-modification, achieving a maximum of 36.6 mg g^-1 for ^152+154Eu. Kinetic data fitted well with the pseudo-second-order model, while the Langmuir isotherm best described the equilibrium behavior. Thermodynamic parameters confirmed the endothermic and spontaneous nature of the adsorption process. These findings demonstrate that CTAB-modified LDH is a promising material for the efficient removal of anionic radionuclide complexes from aqueous solutions.