(中南大学 资源加工与生物工程学院，长沙 410083)
摘 要: 在一水硬铝石的单矿物浮选中，采用油酸为捕收剂，考察增效剂吐温-20对捕收剂油酸的增效作用。通过溶液化学分析、吸附量测定、动电位的测试及液体表面张力的测试等方法揭示了吐温-20的增效机理。结果表明：低浓度的增效剂吐温-20能提高油酸的浮选性能，浮选回收效率提高12%左右；增效剂的增加顺序影响油酸的浮选性能，预先混匀油酸与添加剂的添加方式最佳，油酸与增效剂的最佳质量比为30:1；在pH=9左右，油酸钠以酸-皂聚合体HOl·Ol-与矿物表面作用，因此，其浮选性能及其溶解度与表面活性有关。动电位测试表明，增效剂促进了油酸在矿物表面的吸附，使矿物表面的动电位降低。溶液的表面张力测定显示，增效剂的加入使油酸的临界胶束浓度(cMC)降低，相当于降低了药剂的作用浓度。吸附量检测表明，表面活性剂促进了油酸在矿物表面的吸附，使油酸的吸附量增加。
关键字: 一水硬铝石；油酸；浮选；Tween-20；增效剂
（School of Mineral Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:In single mineral flotation of diaspore, with the oleic acid as collector, the synergistic effect of Tween-20 on the collector was studied. Testing methods of solution chemistry analysis, determination of adsorption and potentiodynamic test, the solution surface tension test reveals the enhancement mechanism of Tween-20. The experimental results show the potentiator has a marked influence on the recovery of diaspore, which is raised by 12% and the addition sequence also affects the flotation behavior. The reagents should be mixed thoroughly before addition and the best mass ratio of collector oleic acid to potentiator Tween-20 is 30:1. At pH 9, sodium oleate acts with the surface of mineral, at the form of acid-soap polymer [HOl·Ol-]. Zeta potential test shows that the potentiator promotes the absorption of collector on the mineral surface, which lowers the Zeta potential. The surface tension experiments results show that the addition of potentiator Tween-20 lowers the cMC value of oleic acid solution, thus resulting in decreasing the agent concentration. By the adsorptive capability tests, with the increasing addition of the Tween-20, the adsorption of oleic acid on diaspore increases.
Key words: diaspore; oleic acid; flotation; Tween-20; potentiator
