金属离子在氧化物矿物/水界面的吸附及浮选活化机理

来源期刊：中南大学学报(自然科学版)1987年第5期

论文作者：胡岳华 王淀佐

文章页码：501 - 508

关键词：阳离子； 浮游选矿； 活化； 化学吸附； 氧化矿物； 液体-固体界面； 氢氧化物； 沉淀物金属离子； 浮选

Key words：cation； floating separation； activation； chemical adsorption； oxide minerals； liquid-solid interfaces； hydroxide； precipitates； metallic ion； flotation

摘    要：本文评述了金属离子活化石英等矿物的-羟基络合物假说.从溶液化学的角度,考察了氧化物矿物/水界面特性、金属离子在界面的吸附及其对ζ-电位和浮选的影响.研究表明:金属离子对氧化矿浮选的活化作用,不能简单地归因子金属离子-羟基络合物的生成,在很多情况下,金属氢氧化物表面沉淀的生成起着更重要的作用.表面沉淀的形成受界面区域金属离子的活度、界面pH值及界面溶度积的控制.金属离子在氧化矿表面的吸附及其对氧化矿ζ-电位和浮选的影响,与表面沉淀的生成条件,有相对应的关系.

Abstract: This paper reviews the mono-hydroxy complex hypothesis of the metallic ion activation of quartz. A number of cases of adsorption of metallic ions on the oxide -water interface and its effect on zeta potential and flotation of oxide mineral in the literatures are analysed based on the thermodynamics and physicochemical principle of interface, It might be concluded that the adsorption and activation mechanism of metallic ion on oxide can not be simply related to the first metal-hydroxy species. In most cases, the surface precipitation of metal hydroxide plays a more important role. The reaction of surface precipitation are controlled by the activities of the species, pH value and solubility product in interfacial region. It has been shown that the sharp increases of adsorption of metallic ion on oxide and flotation response of oxide as well as the charge reverse of mineral surface are correlated with the conditions for surface precipitation. The optimum flotation pH range is predicated to be between CR.3 and CR. 2 which corresponds to the initial pH of the formation of surface precipitation and the PZC of hydroxide, respectively. This has been proved by the flotation results of felspar activated by Al(Ⅲ) and Fe (Ⅲ) with sodium dodecyl sulphate. Activation mechanism may be assumed to be due to the surface precipitation of metal hydroxide resulting in the formation of surfactant-metal salt on the surface of oxide mineral.