Optimized Activity Ratio for Different Types of Reagent Attachment at Sulfide Minerals

摘要

The authors evaluate the ratio of activities exhibited by physical and chemical adsorptions of an agent on sulfide minerals. The following assumptions are made: 1) the main kinetic restriction for flotation contact (particle-bubble interaction) is the film between mineral particle and air bubble; 2) water is removed from the film by both physical and chemical adsorptions; 3) the water volume removed by physical adsorption is conditioned by the difference in the volumes of water in the films bounded by meniscuses with advancing angle TA and receding angle TR and neck radius R. The water volume removed under the action of surface forces (hydrophobic, dispersive) was disregarded as the agent attachment was low dense and mosaic. The article reports experimental data on limit values of static advancing and receding angles on the surface of some sulfide metals. It is shown that selectivity of flotation of sulfides depends on the ratio of water volumes removed from the film by desorbable physical adsorption and non-desorbable chemical adsorption types of agents. The proposed method of selectivity estimation is suitable for minerals with similar (close) properties of the surface when stabilizing ion-electrostatic interaction between minerals and air bubbles is absent or insignificant. The calculation results may be of use to optimizing collecting ability of physically adsorbed low-polar or desorbable species of ionized agent with intent to improve selectivity of separation of sulfide minerals.