Enhanced recovery of fine rare earth minerals using active oil microbubbles: Flotation performance and mechanisms

Fluoro-carbonate rare earth minerals typically exhibit fine-grained dissemination characteristics, and the mineral liberation process often produces excessively fine particles that significantly impair collector efficiency in rare earth flotation. To address this challenge, this study developed an innovative approach by transforming conventional collectors into active oil microbubbles (AOM), thereby dramatically enhancing particle-bubble collision efficiency and flotation performance for fine-grained bastnaesite. The generated microbubbles exhibited an optimal size distribution ( > 90% below 10 μm) and remained stable for over 120 minutes. Compared with conventional collectors, AOM flotation achieved a reduction in reagent dosage, an increase in fine particle recovery, and faster flotation kinetics (89.4% recovery reached within 90 s). Adsorption tests showed that AOM displayed a 4.6-fold higher adsorption capacity (0.96 mg g−1) than conventional collectors, following pseudo-second-order chemisorption behavior. These findings demonstrate that AOM collectors effectively enhance the flotation efficiency of fine-grained bastnaesite through synergistic improvement of stability, adsorption, and collection performance.