Zeta potential as a tool for investigating surface chemistry: implications for mineral flotation

The electrokinetic potential, also known as the zeta potential, refers to the electrical potential at the interface between solid surfaces and the surrounding liquid. Therefore, determining the zeta potential gives an indication of the electrostatic repulsive forces, i.e., helps understand whether these forces are minimised or increased. Establishing these electrostatic repulsive forces assists in establishing reagent interactions at the air–water interface, air–solid interface, and solid-water interface in froth flotation. Understanding these interactions is pivotal in guiding activities such as reagent development and in the development of improved flotation techniques. This study, therefore, presents a review of the application and practical significance of zeta potential measurements in froth flotation. It presents various factors affecting the zeta potential of air bubbles and particles. This review further considers various methodologies used to determine zeta potential. This work concludes with an in-depth study on various experimental techniques that can be used to determine the zeta potential of air bubbles, which is, agreeably, complex and not well explained in both physics and flotation fundamentals literature.