(中南大学 资源加工与生物工程学院，长沙 410083)
摘 要: 通过浮选实验、沉降实验、Zeta电位测试、红外光谱测试和显微镜下观测考察六偏磷酸钠在硫化铜镍矿浮选中的作用，研究六偏磷酸钠的分散作用机理。人工混合矿实验结果表明：镍黄铁矿易与蛇纹石发生异相凝聚，降低镍黄铁矿的浮选回收率；六偏磷酸钠能提高人工混合矿的分散性，实现镍黄铁矿与蛇纹石的浮选分离。硫化铜镍矿实际矿石浮选结果表明：六偏磷酸钠能较好地分散矿浆，当原矿镍品位为0.33%时，通过两次粗选就能得到合格的镍精矿产品，镍总回收率为80.27%。作用机理研究表明：六偏磷酸钠通过化学吸附以及溶出蛇纹石表面的镁离子两种方式调整蛇纹石的表面电性，进而分散镍黄铁矿与蛇纹石。
关键字: 六偏磷酸钠；硫化铜镍矿；蛇纹石；分散；浮选
（School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:Through flotation tests, sedimentation experiments, zeta potential measurements, infrared spectroscopic analysis and observation under microscope, the effect of sodium hexametaphosphate (SHMP) on the flotation of copper-nickel sulphide was investigated, and the dispersive mechanism of sodium hexametaphosphate was studied. The results of tests on artificial mixed mineral show that the hetero-coagulation between pentlandite and serpentine decreases the flotation recovery of pentlandite, the sodium hexametaphosphate can fulfil the flotation separation of pentlandite and serpentine by promoting the dispersion of artificial mixed mineral. The flotation results of copper-nickel sulphide ores indicate that sodium hexametaphosphate can disperse pulp effectively. The qualified nickel concentrate products can be obtained by two roughing with total nickel recovery of 80.27%. The mechanisms demonstrate that the sodium hexametaphosphate adjusts the surface potential of serpentine through chemical adsorption and dissolving magnesium ions from serpentine surface, and then disperses pentlandite and serpentine.
Key words: sodium hexametaphosphate; copper-nickel sulphide; serpentine; dispersion; flotation
