Separation of Gallium from the Akaline Solution of Bauxite Sintering Process

During the production of alumina from low-grade bauxite via the sintering process, gallium (Ga) is simultaneously transferred into the leach liquor. The ion exchange and solvent extraction were employed to evaluate the selective separation of Ga from bauxite sintering leach liquor. The separation of Ga and aluminum (Al) from bauxite sintering leach liquor was investigated using SEPLITE ® LSC-600 special chelating resin (Sunresin New Materials Co., Ltd., Xi’an, China) as the adsorbent and a trioctylmethylammonium chloride (N263)-based organic solvent as the extractant. For the LSC-600 resin, an adsorption efficiency of 79.70% and a distribution coefficient of 31.42 mL/g for Ga were achieved at a solid-to-liquid (S/L) ratio of 2.5/20 with a contact time of 30 min. In comparison, the N263 organic solvent yielded a Ga extraction efficiency of 89.23% and a distribution coefficient of 82.89 at an organic-to-aqueous (O/A) ratio of 2/20 and a contact time of 15 min. Although N263 outperformed the LSC-600 resin in terms of extraction performance, the subsequent stripping process using hydrochloric acid (HCl) proved to be relatively challenging. This work demonstrates that N263 serves as a highly effective extractant for selective gallium recovery from alkaline leach liquor, providing a new approach for the comprehensive utilization of low-grade bauxite. Graphical