First Report on a 1-Cycle Solid-Phase Extraction Method for Selective Separation of Am³⁺ and Eu³⁺: Use of BTP-Grafted Silica Decorated on Activated Carbon

Abstract

A new composite sorbent material was prepared by grafting bistriazinylpyridine (BTP) onto silica and then blending it with activated charcoal (AC− Si−BTP) for the selective separation of Am 3+ over Eu 3+ using a 1-cycle solid-phase extraction for the direct separation of lanthanides from actinides. BTP was attached to silica via a sulfonamide bond between R−BTP and amino silane, and the resulting Si− BTP was covalently bonded to activated carbon (AC) with a favorable orientation of the ligand coordination sites. The material exhibited a significantly large distribution coefficient for Am 3+ over Eu 3+ at lower acidities (<0.5 M HNO 3 ), and the separation factor between the two metal ions was found to be maximum in 0.2 M HNO 3 with a value of 110. The loading capacity of the material was 4.05 ± 0.12 mg of Eu per gram of the composite when investigated at pH 3. The radiation stability of the material was excellent when studied up to an absorbed dose of 1000 kGy. The material was tested for the separation of Am 3+ and Eu 3+ in a column mode, which gave selective loading of Am 3+ over Eu 3+ . The reusability studies indicated slow leaching of the BTP fraction from the solid, with a resultant decrease of the K d values with time. To address this issue, the material was embedded in polysulfone beads for a separate set of studies, but the separation efficiencies were found to be comparable.

Adsorption of Europium (III) on Amidoxime-Functionalized Ficus virens Aerial Root Hydrochar: Statistical Optimization, Equilibrium Isotherm, and Kinetic Analyses

“…Europium, the most active metal among rare-earth metals, is used in control rods as an effective neutron absorber in nuclear reactors and is one of the tenacious radionuclides in nuclear effluents owing to its extended half-life . It is one of the primary constituents of wastewater generated in the processing of bastnasite and monazite and the radioactive waste from the fission of uranium-235 fuel rods where its concentration is higher with a varying pH range compared to the natural waters . The higher environmental mobility of Eu 3+ has impelled its widespread distribution in the environment and bioaccumulation and consequently presents impending toxic and radioactive effects on both aquatic ecosystems and human health .…”