Droplet coalescence in aqueous electrolyte solutions

Abstract

A study is described of the effect of inorganic electrolytes on the rate of coalescence of organic droplets in an aqueous continuous phase. It was found that the addition of ionizing salts to the aqueous phase resulted in an increase in coalescence time at a flat interface with droplets of polar organic liquids, such as butyl acetate. In contrast, no change in coalescence time was observed for nonpolar droplets such as heptane. These results are discussed in relation to existing theories of drop coalescence, and a qualitative explanation of the phenomenon is proposed in terms of an increase in the interfacial viscosity. © 1990.