Mass Transfer and Chemical Reaction in Liquid-Liquid Agitation Systems

Abstract

The objectives of the agitation of liquid-liquid mass transfer systems with or without chemical reaction may be set forth as follows in general : (1) increase in the inter facial area by promoting dispersion, (2) diminution of the mass transfer resistance in the diffusion film outside the liquid droplets, and (3) diminution of the mass transfer resistance in the inner part of liquid droplets or mixing of dispersed phase. The diameter of liquid droplets was measured to estimate the interfacial area. At the same time, the rate of reaction or the rate of mass transfer was observed for various kinds of liquid-liquid mass transfer systems which were classified according to reaction or no reaction and according to degree of difference in density. Comparison was then made between the increase in the estimated inter facial area and the increase in the rate of reaction caused by the increase in agitator speed. On the other hand, mathematical analysis were performed on these processes to clarify the effect of agitation for various kinds of fundamental and important liquid-liquid agitation systems. Thus the authors found that the effect of agitation upon the liquid-liquid mass transfer was mainly to increase the interfacial area, that the decrease of the mass transfer resistance in the diffusion film outside droplets was slight, and that the mixing of the inner part of the droplets was rather decreased by the increase in agitator speed. Part I Effect of Agitation for the Diminution of Mass Transfer Resistance in Continuous Phase.