Mass transfer between isobutanol and water in a spray-column

Abstract A study of the rate of mass transfer across a liquid boundary between a discontinuous and a continuous phase, using a binary mixture and a droplet system has been made. Because of differences in density and movement of the drops the continuous phase appeared to be thoroughly mixed. This resulted in a nearly constant concentration independent of the height of the column. For the continuous phase a relation for the partial mass transfer coefficient k c in the form k c d d / D = Sh = h Re d 1 2 Sc c 1 2 has been used. Satisfactory correlation of the experimental results could be obtained with this equation. The constant x in the above relation appeared to be a function of the relative interfacial velocity which in turn is a function of the viscosities of the drops and the surrounding fluids. Following the concept of H adamard this function is taken as η c /η c +η d . This picture of the mechanism is representative of the situation, when the circulation in the drop is not restricted by interfacial tension. For transfer to the discontinuous phase the unsteady state equation of K ronig and B rink , considering the occurrence of internal droplet circulation, was shown to express fairly adequately the experimental results for free rise of isobutanol droplets. Water drops showed a divergence from the Kronig-line possibly due to the “floating” effect of water droplets in isobutanol.