What is adsorption? What is the significance of adsorption for flotation?

Adsorption is the phenomenon that the concentration of a substance in a liquid or gas increases or decreases at the phase interface. Magnesium ore flotation equipment, when adding a certain solute to the solution, reduces the surface free energy of the solution, and the concentration of the surface layer solute is greater than the internal concentration of the solution, the solute is called a surface active substance (or surfactant). Such adsorption is called positive adsorption. Conversely, if after adding solute, the surface free energy of the solution is increased, and the solute concentration of the surface layer is small and the concentration inside the liquid, the solute is said to be a non-surface-active substance (or non-surfactant), such adsorption is Negative adsorption.

The significance of adsorption on flotation. Flotation is carried out in three phases of gas, liquid, and solid. Therefore, adsorption is the main form of interaction between minerals, reagents, and bubbles, along with the entire flotation process. For example, when chemicals are added to the slurry, some chemicals (such as collectors and modifiers) are adsorbed on the solid-liquid-interface, which directly affects the physical and chemical properties of the mineral surface, thereby adjusting the floatability of the mineral and achieving mineral separation The purpose of the election. There are also some agents (such as foaming agents) adsorbed on the gas-liquid interface, which reduces the free energy of the liquid-gas interface, prevents bubbles from merging and breaking, improves the stability and dispersion of the bubbles, and promotes the formation of stable minerals by foams and minerals The purpose of the foam layer is to effectively recover the target minerals.