Solvent extraction processes are widely used to purify, recover or recycle solutes, by transferring it from an aqueous phase to an organic phase. In these processes, the direct contact between the two liquids at the oil-water interface is an important factor. Increasing the interfacial areas by drop breakage and fast droplet coalescence will lead to an enhancement in process efficiency. Controlling the interaction between droplets and the forces acting at liquid-liquid interfaces is one of the key factors in controlling these processes. Therefore, a fundamental understanding of interaction forces at liquid-liquid interfaces is required, but they are not yet well understood and their direct measurements remain a challenge. In this article we review recent experimental techniques used to measure forces at liquid-liquid interfaces.
Solvent Extraction Research and Development, Japan,
Vol. 15 (2008), pp. 1-10