铁离子对辉钼矿表面性质及可浮性的影响机理研究

Study on Influence of Fe^(3+) on the Surface Properties and Flotation of the Molybdenite

通过纯矿物的浮选试验、电动电位测试、Fe^(3+)溶液化学分析、以及X射线光电子能谱分析(XPS),系统地研究了Fe^(3+)对辉钼矿表面性质、可浮性的影响及其作用机制。结果表明,Fe^(3+)的加入明显降低了辉钼矿的浮选回收率;Fe^(3+)在辉钼矿表面发生了较强的吸附,辉钼矿经Fe^(3+)作用后其表面电位发生显著偏移;Fe^(3+)在溶液中主要以羟基络合铁离子、氢氧化铁沉淀及少量铁离子形态存在,其中羟基络合铁离子、氢氧化铁沉淀具有极强的极性,能吸附在辉钼矿上,而铁离子能与辉钼矿棱氧化生成的MoO_4^(2-)发生化学反应;由于辉钼矿棱的面积要比面的面积小,而铁离子主要是吸附在棱上,因此由XPS检测分析可知,铁元素的峰不明显,铁的含量不多,但可以看出铁离子吸附在辉钼矿表面,且吸附既有物理吸附也有化学吸附。

Influences of Fe3＋ on molybdenite surface properties, flotation and its mechanism of action were systematically studied, through flotation tests of pure molybdenite, measurement of electric potential, Fe3＋ solution chemical analysis, and XPS test. The results indicate that the flotation recovery of the molybdenite deposit was significantly reduced with the addition of Fe3 ＋. Fe3＋ is absorbed strongly on the surface of molybdenite and the surface potential of molybdenite significantly shifts after action of Fe3＋. Fe3＋ in solution mainly exists in the form of hydroxyl complexation iron, iron hydroxide precipitation and a small amount of iron ions. Hydroxyl complexation iron and iron hydroxide precipitation with a strong polarity can absorb on molybdenite. Iron ion could react with MoO42- generated because of molybdenite edge oxidation. With the reason of the area of molybden μm edges smaller than that of the surface area, and the iron ions mainly adsorbed on the edge, so from the analysis of XPS detection, iron peak is not obvious, and iron content is not much, but it can be concluded that iron ion could adsorb on the surface of molybdenite. The forms of adsorption are both physical adsorption and chemical adsorption.