The role of mixing in high performance Adsorptive Micellar Flocculation

Abstract

Two alternative mechanisms allow the capture of pollutants by Adsorptive Micellar Flocculation: adsorption of organic molecules as Al 3+-complexes onto the surface of micelles (e.g. benzoic acid), and solubilisation of organic molecules into the micelles, facilitated by higher hydrophobicity of the micellar phase and enhanced transfer through the palisade by complexation with Al 3+ (e.g. phenol). The impact of each of the mechanism is dependent on the mixing conditions, and the balance between them can be used to optimize the separation of different types of pollutants. The data obtained indicate that a seven-step AMF process operating within the same time scale (about 2 h) than a MEUF separation would reduce the concentration of phenol in water from 0.128 M (12,000 ppm) to about 0.0021 M (200 ppm), with an efficiency of more than 98%. The results represent the highest amounts of phenol removed from water by membrane or surfactant-mediated separation ever reported.