Mass Transfer between Drops of Organic Solvents and Water

Abstract

In the previous paper3), it was reported that the rate of mass transfer between drops of organic solvents and water was reduced by the addition of some substances. In the present work, a study on the rate of extraction from drops of organic solvents to drops in pure systems has been made paying special attention to these poisonous substances. For butylacetate, -IPE-and MIBK-water systems which are not liable to be contaminated easily, results agreed approximately with the published data (Table 2), but the observed Kd values were much larger than the published data for the benzene-water system (Table1). This discrepancy between the author's and the published data cannot be accounted for by any experimental errors. It seems likely that it is due to difference in purity of the benzenes, solutes and waters used and to the resultant contamination by trace quantities of poisonous substances.The observed Kd values were largest at the beginning of free rise, and they decreased when the height of rise increased due to the transfer of acetic acid or propionic acid whose distribution favors water.The observed Kd values for 24 systems (3 solutes and 8 solvents) were compared with the predicted Kd volues which were calculated by Eq. (3) for kd and ke (Fig. 8). The over-all mass transfer coefficients for non-contaminated systems can be approximately predicted by Eq. (3), but further studies with due attention to poisovous substances will have to be carried out to obtain more accurate correlations.