Structure Investigation of La, Y, and Nd Complexes in Solvent Extraction Process with Liquid Phosphine Oxide, Phosphinic Acid, and Amine Extractants

Author(s)

Botelho, Amilton Barbosa ; da Silva, Natalia Olim Martins ; Tenorio, Jorge Alberto Soares ; Espinosa, Denise Crocce Romano

• Document type: Journal article
• Source: METALS; v. 13, n. 8, p. 16-pg., 2023-08-01.

Abstract

The main challenge in separating REEs through hydrometallurgical processes is their chemical similarities. Despite the literature widely presenting the possibilities for organic extractants, there is a lack of evaluation of the structures formed between the REEs and the extractants. The present study aimed to evaluate different extractants (neutral, anionic, and acid extractants) for separating La, Y, and Nd. The extraction efficiencies were evaluated, and the structure investigation was carried out in FT-IR. From the results obtained, it is clear that the extraction order is Alamine 336 <<< Cyanex 272 < Cyanex 923, where both acid extractants were more selective for Y than for La and Nd. The extraction achieved 99% at pH 5.0 in nitric acid media, and a Y/La ratio of 2 and a Y/Nd ratio of 4 using Cyanex 923. The present study also elucidated the organometallic complexation between Cyanex 923 and Cyanex 272 with Y and La, which may improve separation processes to obtain critical metals from primary and secondary sources. (AU)

• FAPESP's process: 19/11866-5 - Development of innovative processes for the recovery of critical metals
• Grantee: Denise Crocce Romano Espinosa
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 21/14842-0 - Elucidation of the organometallic complexation mechanism between organic extractants and rare earth elements
• Grantee: Amilton Barbosa Botelho Junior
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 23/01032-5 - Separation of critical metals through supported liquid membrane: evaluation of synergistic interaction between organophosphorus and membranes
• Grantee: Amilton Barbosa Botelho Junior
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor