INFLUENCE OF TETRADECYLAMINE CHLORIDE ON THE SURFACE FREE-ENERGY COMPONENTS AND FLOTABILITY OF BARITE

The concept presented by van Oss et al. of the surface free-energy components: apolar, (Lifshitz-van der Waals LW), and polar (electron donor/electron acceptor SR) is used in a model system: barite/tetradecylamine chloride (TDACl) water. The components have been determined for bare, 0.25, and 1.0 TDACl covered barite surfaces. The values were obtained from glycerol (or water) contact angles and by using a method in which zeta potentials were measured for a series of barite/TDACl/n-hexane (n-hexanol) film samples in water. From the determined surface free-energy components, the values of DELTAG for particular samples were calculated. Negative DELTAG is the thermodynamic condition for effective flotation. This condition states that the work of water adhesion to the surface must be less than the work of water cohesion. Full agreement between the flotation activity of the samples and the DELTAG magnitude was found. We conclude that experimentally determined components are useful quantities for explaining some interfacial phenomena.