Effect of Innovative Mixed Collectors on the Improvement of Flotation Recovery of Lepidolite-Spodumene Ore

Lepidolite and spodumene are important lithium sources that are concentrated through a flotation process. However, the main collectors for lithium ore are homogeneous surfactants ODA (C₁₈H₃₉N) and DDA(C₁₂H₂₈ClN) with one hydrophobic group and hydrophilic chain, which typically exhibit low selective flotation efficiency. Therefore, this study aimed to investigate using a mixed collector system with an amine-based combined surfactant, sodium dodecyl sulfate (SDS) + sodium oleate (NaOL):octadecylamine (ODA) 3:1 (IM-11) + (SDS) 1:1 and a mixture of dodecyl methylamino bromide (DDAB) + dodecylamine hydrochloride (DDA) 1:1 for the lithium flotation and to compare this with a conventional single-molecule benzenesulfonic acid (BSA). According to the results, when the pH was 11.3, the SDS + NaOL + ODA 3:1 and IM11 + SDS 1:1 mixture of lepidolite ore enriched the pure lithium content to 2.52%. The zeta potential results showed that the washed surface was more adsorbed than the main surface of the lithium ore. The results also indicated that the SDS + NaOL + ODA and IM11 + SDS combination is more suitable for the main surface of lithium and more adsorbed on the surface of lepidolite. The economic assessment of lepidolite and spodumene ores shows that using a combination of SDS + IM11 can be more profitable than when using the single-molecule BSA. This study describes a novel, high-efficiency collector mechanism for flotation beneficiation of lepidolite ore.