Abstract: | Foam separation has been investigated as a technique for removing ethylhexadecyldimethylammonium bromide, a cationic surfactant, from dilute solutions. An ideal foam model has been used to determine the surface excess accumulated at the solution-air interface and to predict the foam and drain concentration in a continuous foam separation process. It was found that the model was valid only under conditions of good drainage and perfect foam stability. An increase in column diameter for a feed of constant composition and supplied at a constant rate increased the concentration of the surfactant in the overhead stream. This highly desirable effect was accompanied by an increase in the drain rate. The results indicate that an increase in column diameter had an entirely beneficial effect on the efficiency of the separation. |