BEHAVIOR OF THE INTERFACE BETWEEN LIQUID BISMUTH AND MOLTEN SODIUM-CHLORIDE AT LARGE ANODIC POLARIZATION

Some new features of phase transitions in a liquid bismuth-molten sodium chloride system were established. These are caused by extreme anodic polarization of the interface between immiscible liquids with metallic and ionic bonds between species and were investigated using measurements of the difference between the heights of liquid columns in the arms of communicating vessels of different cross sections. As the potential shifts toward the potential of anodic dissolution, the interfacial tension and its derivative with respect to the potential decrease. At a certain value of the potential, inversion of the meniscus occurs, when the interface changes the sign of its curvature and a film of the metal phase penetrates between the wall and the salt phase, which completely wets this wall. It was found that near the potential of meniscus inversion the dependence between this potential and the interfacial tension can be expressed as a power-law function with the value of the exponent close to 0.1. The results are discussed from the viewpoint of the interaction between the ionic components of the metal and salt phases, which increases and extends beyond the boundaries of the domain of physical contact between phases as this domain approaches its critical state.