Two-phase electrophoresis separation of dyestuffs from dilute solution

Abstract

Dyestuffs are not efficiently removed by biological treatment or by conventional dye treatment techniques. New separation techniques are required. Two-phase electrophoresis, a coupled separation technique of solvent extraction with electrophoresis, can be used to remove dyestuffs from dye effluents. A study on the characteristics of the separation technique has been carried out with n-butanol–acid-chrome blue K–water, n-butanol–methyl blue–water and n-butanol–methyl red–water as working systems. Continuous separation equipment has been designed and used in this work. The influences of the two-phase flow rate, field strength and feed concentration on the recovery are studied. The results show that a high recovery with less solvent consumption can be achieved using this technique, especially for the separation of dilute solutions. As the field strength is increased, the recovery and mass flux increase. When the feed flow rate and the initial solute concentration in the feed are increased, the recovery decreases and the mass flux increases.