硫代水杨酸在霓石和镜铁矿浮选过程中的选择性抑制作用

Selective depression effect of thiosalicylic acid in the flotation process of aegirite and specularite

针对含铁硅酸盐脉石霓石自身密度、比磁化系数和矿物表面性质与氧化铁矿相近而难以分离的问题,采用浮选试验研究了以油酸钠(NaOL)为捕收剂条件下硫代水杨酸(TSA)对镜铁矿和霓石可浮性的影响,并利用红外光谱(FTIR)、吸附量测定、Zeta电位检测、X射线光电子能谱(XPS)分析和玻尔兹曼理论分析等方法研究了TSA对霓石的抑制机理.结果表明:TSA对霓石有显著的抑制作用,对镜铁矿几乎无抑制作用.该试验条件下,TSA主要吸附在霓石表面,致使霓石的零电点由3.3左移至1.0,而在镜铁矿表面吸附较少,零电点变化微弱.TSA中的—SH基团在吸附过程中与霓石表面金属离子结合生成金属络合物,亲水基团—COOH增加了霓石的亲水性,扩大了霓石和镜铁矿的亲水性差异,实现了对霓石的选择性抑制作用.

To solve the problem that the iron-bearing silicate gangue aegirite is difficult to separate because of its own density, specific magnetization coefficient and mineral surface properties similar to those of iron oxide. The effect of thiosalicylic acid(TSA) on the floatability of specularite and aegirite under the condition of sodium oleate(NaOL) as collector was investigated by flotation test, and the depression mechanism of TSA on aegirite was studied by infrared spectroscopy(FTIR), adsorption tests, Zeta potential detection, XPS analyses and Boltzmann theory analysis. The results show that TSA has a significant depression effect on aegirite and almost no depression effect on specularite. TSA mainly adsorbes on the surface of aegirite, resulting in a leftward shift of the iso-electric point of aegirite from 3.3 to 1.0, while it adsorbes less on the surface of specularite and its iso-electric point changes weakly. The —SH group in TSA combines with metal ions on the surface of aegirite to form metal complexes during the adsorption process, and the hydrophilic group —COOH increases the hydrophilicity of aegirite, which widenes the hydrophilic difference between aegirite and specularite, and achieves the selective depression effect on aegirite.