Effects of Surfactants and Electrolytes on the Nucleation of Bubbles in Gas-Supersaturated Solutions

Abstract

Various solutions of surfactants and electrolytes were equilibrated with argon at gas pressures up to 202 atm and then decompressed to atmospheric pressure while observed visually or cinemicrographically for occurrence of bubbles. In water, the threshold gas supersaturations for spontaneous nucleation of bubbles at the glass-water interface and in the bulk liquid were 135 atm and 155 atm, respectively. Among the surfactants, only those of molecular weight less than about 330 daltons significantly decreased the cavitation thresholds; those of higher weights had no effect. The electrolytes either had small to moderate or no effect on the threshold, although the dissolved gas concentrations resulting from the solubility changes were greatly decreased. The data indicate that changes in the structure of the solvent water may affect the nucleation process.