Lanthanide recovery by silica-Cyanex 272 material immobilized in alginate matrix

Abstract

Mesoporous silica impregnate with Cyanex 272 (bis/2,4,4-trimethylpentyl/phosphinic acid) extractant was immobilized into an alginate matrix to obtain a composite sorbent easy to use and applicable in fixed-bed column continuous systems. The sorption efficiency of this material was tested for the recovery of Eu(III) ions from aqueous solutions in batch and continuous mode. The competition among rare earths ions (europium, lanthanum, and lutetium) and among rare earths and calcium or sodium ions was investigated. High calcium concentrations strongly reduce the sorption capacity of the alginate matrix that composes the hybrid material and the Cyanex 272 impregnated into silica powder improves the rare earths' sorption performance in this calcium charged media. The experimental breakthrough curves obtained were satisfactory fitted by Thomas model.

Enhancing the Recovery of Rare Earth Elements from Red Mud

“…REEs are presumed to be worth recovering from RM owing to their high economic value and importance in industrial applications 17, 19, 20. The recovery of REEs has not only been focused on a single process, but also the incorporation of REE recovery into the complex utilization of RM is being considered as an economically beneficial and waste‐free goal 21. The presence of one of these REEs, namely Sc, accounts for more than 90 % of the trace metal value in RM 22.…”

“…Some literature data on the leaching of REEs from bauxite residues are available 4, 10–13, 15, 16. There are also some literature data on the leaching of REEs from bauxite residues 10, 19, 21–23, 26–30. A previous study 15 investigated metal leaching extraction with various acids, acid concentrations, and leaching conditions.…”

Extraction of Rare Earth Metals by Solid-Phase Extractants from Phosphoric Acid Solution

“…Mohammedi et al [11] proposed a composite sorbent for extracting Eu (III). The sorbent is a mesoporous silicon dioxide coated with a surface layer of Cyanex 272 extractant impregnated and immobilized in an alginate matrix.…”