(中南大学 资源加工与生物工程学院，长沙 410083)
摘 要: 通过矿物浮选实验、沉降实验、动电位和DLVO理论计算，考察氯化钠在蛇纹石/黄铁矿浮选体系中的聚集/分散作用，研究氯化钠对颗粒间的分散作用机制。结果表明：蛇纹石颗粒可通过异相凝聚作用罩盖在黄铁矿表面，阻碍黄药在黄铁矿表面吸附，影响黄铁矿的浮选；氯化钠的加入能增加蛇纹石与黄铁矿颗粒间的分散性，提高黄铁矿/蛇纹石混合矿体系中黄铁矿的回收率。研究结果表明，在pH为8.5时，氯化钠的浓度越高，对混合矿颗粒间的分散性越强；蛇纹石通过静电作用吸附在黄铁矿表面影响其浮选，氯化钠加入压缩双电层，使带相反电性的颗粒间电位绝对值显著降低，降低静电引力，使异相凝聚程度减弱，降低蛇纹石对黄铁矿的抑制作用。
关键字: 黄铁矿；蛇纹石；氯化钠；分散；作用机理
（School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:The aggregation/dispersion effect of sodium chloride on flotation system of serpentine and pyrite and its mechanism were studied by flotation experiments, sedimentation tests, zeta potential and calculations of DLVO theory. The results show that the serpentine particles shroud on pyrite surface by hetero-aggregation, depress the adsorption of xanthate on pyrite surface and decrease the flotation recovery rate of pyrite. The dispersion between particles of the serpentine and pyrite increases in the presence of sodium chloride. The higher concentration of sodium chloride is added, the higher dispersion exists between the particles. Sodium chloride adjusts the surface potential of serpentine through compressing double electrode layer and then disperses serpentine and pyrite, then improving the flotation performance of pyrite.
Key words: pyrite; serpentine; sodium chloride; dispersion; mechanism
