Experimental Investigation of the Effects of Surfactants on the Mass Transfer in Liquid-Liquid Extraction Equipments

Mass transfer rates to the drops in liquid-liquid extraction equipment are often likely to be reduced by the presence of surface active contaminants. This reduction in mass transfer is said to be due to a reduction in terminal velocity, and to changes in pattern of internal circulation. A single-drop extraction apparatus was used to investigate the dependency of mass transfer coefficient on the amount of surfactant added in a system of n-butanol/succinic acid/water. Three types of surfactants, SDS, DTMAC and Triton X-100, were used to study their effects on the inhibition of mass transfer in liquid-liquid extraction. The effect of surfactants concentration on extraction percentage, overall mass transfer coefficient, and extra mass transfer resistance was investigated for these surfactants. Also variation of terminal velocity as a function of surfactant concentration and drop diameter were illustrated for both surfactants. Finally these surfactants were compared to each other.