Interfacial phenomena in metal-slag reactions: past, present and future

Interfacial phenomena, which include interface turbulence, lowering of apparent interfacial tension, and spontaneous emulsification, have been observed in high temperature metal processes involving reactions between liquid metals and liquid slags. The major importance of these phenomena are that they can increase the reacting interface up to five hundred percent of initial value and can also increase mass transfer rate, thus significantly enhances the overall reaction rate. It has been almost six decades since the phenomena was first documented in laboratory by Kozakevitch using x-ray radiography technique and numerous studies have been carried out since then. However, the complexities of the problem, limitations in experimental techniques, difficulties in experimental work resulting in the lack of quantitative experimental data, among many, prevent the holistic understanding of the phenomena. The current paper will review the previous studies, the present understanding and challenges as well as the future research on interfacial phenomena in slag-metal reactions along with their potential application for a new advanced metal processing.