Work

Preparation of a Porous Tri-n-decylamine Modified Adsorbent for the Efficient Removal of Uranium and Iron from Rare Earth

Year: 2025

Type: article

Abstract: The presence of impurities Fe and trace radioactive U in rare earths may lead to a significant decline in the performance of high-purity rare earth products. To remove them from rare earths in a green and efficient way, an amine-based silicon functional adsorbent TNDA/SiO2-P was prepared by simple vacuum impregnation method, which has a high organic loading rate of 31.2 wt.%. The experimental results show that it exhibited good adsorption selectivity for uranium and iron with the separation factors SF(U/RE) = 20147, SF(Fe/RE) = 88128 in 5 M HCl. The adsorption kinetics was fast with equilibrium obtained in 60 min. 0.1 M hydrochloric acid can desorb U and iron. The deep removal of U and Fe from rare earths including scandium can be achieved through chromatographic columns. FT-IR, XPS and DFT calculations mutually confirmed the selectivity mechanism that the positive charged protonation TNDA/SiO2-P adsorbs the complex anions of U and iron in the hydrochloric acid system protonation U and Fe by protonation and carrying positive charge under high acid conditions, adsorbing. The adsorbent exhibits exceptional potential for the production of ultra-high-purity rare earth elements (REEs), offering superior selectivity and efficiency in separation processes.

Source: Metals

DOI: 10.3390/met15101064