CHARACTERIZATION OF THE WETTABILITY OF SOLID PARTICLES BY FILM FLOTATION .2. THEORETICAL-ANALYSIS

This paper presents a model of the film flotation process, which is a useful technique for characterizing the wetting behavior of particulates, especially those with heterogeneous surfaces. Two different approaches were used, one involving the total and the other the differential free energy for the process of transferring particles from a liquid/vapor interface into the liquid phase in film flotation. Analysis shows that interfacial energy has dominant control over the behavior of particles in film flotation over a wide range of particle size and solid density. This study confirms theoretically that the critical wetting surface tension of a particle is equal to the value of the surface tension of a wetting liquid at which particles are just imbibed into the wetting liquid.