Droplet Circulation and Interfacial Disturbances in Gas-Liquid Systems

Abstract

DURING recent years the process of liquid-liquid extraction has become progressively more important and the mechanism of solute transfer between liquid droplets and a second substantially immiscible liquid environment has received considerable attention. In the course of their work in this field, Lewis and Pratt¹ observed that when solute transfer, for example, acetone, occurred between hydrocarbon droplets and water, then in many cases, the droplets exhibited rapid and violent oscillations which they termed ‘kicking’. Systems which exhibited this effect were found to have higher mass transfer rates than those predicted from theoretical considerations². More recently the phenomenon of droplet oscillation in liquid-liquid systems has been the subject of extensive study, notably by Haydon³ and Davies and Haydon⁴. These workers concluded that droplet oscillation was the result of the interfacial solute concentration becoming non-uniform, thereby giving rise to local interfacial tension variations which resulted in temporary droplet instability.