Enhanced separation of europium radionuclides from active solutions using a novel sorbent of gadolinium metal–organic framework

Preserving environmental quality when disposing of hazardous waste, especially radioactive waste, is a relevant research area that attracts the interest of global scientists. The separation of harmful species on the surface of novel adsorbent metal-organic frameworks (MOFs) is a promising and effective method for achieving this goal. This study identifies a new metal-organic framework known as melamine-terephthalic acid (MTGd MOF) that was synthesized and then treated with oxalic acid to produce modified MTGd-OX MOF that has been characterized. The MOFs were formed successfully based on the characterization results. BET results show that MTGd MOF and MTGd-OX MOF have surface areas of 1857.40 and 1955.16 m² g^-1, respectively. The prepared materials were used in batch studies to explore the sorption behavior of Eu radionuclides onto unmodified and modified MOFs. The results indicate that MTGd-OX MOF had a more effective sorption capacity than MTGd MOF. Several variables, including the pH, ionic strength, initial concentration of ^152+154Eu ions, contact time, and optimal conditions for separating ^152+154Eu onto MTGd-OX MOF, were examined, including temperature. The MTGd-OX MOF capacity is about 37.22 mg g^-1 at pH 3.5, and the equilibrium was reached after 4 hours. The efficiency of MTGd-OX MOF as a sorbent was assessed by analyzing a real waste sample, which showed it had significant sorption efficiency.