javad saien - Department of Applied Chemistry, University of Bu-Ali Sina, Hamadan,Iran
Shabnam Daliri - Department of Applied Chemistry, University of Bu-Ali Sina, Hamadan,Iran

The influence of aqueous phase pH on the rate of liquidliquid extraction was investigated using single drop experiments with mass transfer in either direction and for a range of drop size. The chemical system of tolueneacetone- water was employed. To do this, pH of aqueous phase was adjusted at desired values of 5.5, 6, 6.5, 7, 7.5 and 8. These pH values are around the natural water pH in environment. The increase of pH caused a significant reduction in overall mass transfer coefficient. The rate of mass transfer was also greater for dispersed to continuous phase direction.

Liquid-liquid extraction – Mass transfer coefficient – pH – Mass transfer direction