Abstract: Taking the lithium-containing tailings of a concentrator in Jiangxi Province as the object, the flotation process optimization test was systematically carried out to solve the problem of fine-grained lith⁃ ium mica recovery. The process mineralogy analysis shows that the content of Li2O in the tailings is 0.30%, and the lepidolite is mostly in the form of intergrowth in the coarse fraction. It is necessary to improve the dis⁃ sociation degree of lepidolite monomer by grinding. Under the condition of grinding fineness of -0.074 mm accounting for 85%, after desliming by cyclone, hydrochloric acid and sodium hydroxide were used as pH regulators, sodium silicate was used as inhibitor, and dodecylamine/sodium dodecyl benzene sulfonate was used as combined collector. After one roughing, four cleanings and three scavenging, lepidolite flotation con⁃ centrate with Li2O content of 1.98% and Li2O recovery of 67.12% was obtained. The electrokinetic potential test showed that the anionic collector could be adsorbed between the dodecylamine cations by electrostatic force, and the hydrophobic association between the carbon chains further stabilized the adsorption of the an⁃ ionic collector on the surface of lepidolite. Because the neutralization efficiency of sodium dodecyl benzene sulfonate on the cationic charge of dodecylamine is better than that of sodium oleate, the Li2O grade and re⁃ covery of flotation concentrate are higher under the action of dodecylamine/ sodium dodecyl benzene sulfo⁃ nate.

Key words: lepidolite, re-separation of tailings, anionic/cationic mixed collector, flotation