Effect of different particle size fractions on flotation separation of fine rutile from garnet

The flotation separation of fine minerals, including rutile, has long been a challenging research focus. This study selected rutile and garnet samples with size fractions of −15, −38, and −74 μm to investigate the impact of particle size on flotation separation. Infrared spectroscopy, Zeta potential analysis, adsorption capacity measurements, and high-speed camera were utilized to analyze the mechanism. Results indicate that a high-grade concentrate with recovery of 92.33 % was achieved by mixing −74 μm rutile and −15 μm garnet in a 1:1 ratio. Benzohydroxamic acid (BHA) collector primarily chemisorbs onto the surface of rutile particles. BHA's adsorption capacity on each particle size's rutile surface is significantly higher than that of garnet. Meanwhile, sodium fluorosilicate (SSF) exhibits the strongest inhibitory effect on −15 μm garnet particles. Additionally, adhesion between bubbles and −74 μm rutile is much stronger than that between bubbles and fine particles overall. These findings have significant reference value for improving eclogite-type rutile ore's fine particle separation.