Limits of Cyanex 272 Selectivity for Cobalt Extraction in A Multi-Cationic Industrial Environment: Case Study of Lamikal, Lualaba (DRC)

This study examines the limits of Cyanex 272's absorption capacity in a complex industrial solvent extraction (SX) process for cobalt, applied at the LAMIKAL plants (Lualaba, DRC). The objective is to evaluate the actual performance of Cyanex 272 under multi-metal industrial conditions, where cobalt, copper and manganese coexist. Operating parameters such as pH, extractant concentration, organic/aqueous ratio (O/A) and contact time were optimised. The results show a cobalt extraction yield limited to 31.5%, compared to 98.6% for copper and 97.9% for manganese, revealing a low selectivity of Cyanex 272 towards cobalt in the presence of impurities. Recommendations are made to improve the selectivity of the process in a real industrial context.