THEORETICAL-STUDY OF CRITICAL MICELLE CONCENTRATION DETERMINATION BY FLOW-INJECTION ANALYSIS

Most critical micelle concentration (CMC) determination are performed experimentally by monitoring the change of a physicochemical property of the solution with increasing surfactant concentrations. A rapid and efficient method for determining surfactant CMC is to use flow injection analysis. A theoretical model which explains conductimetric results and which allows optimization of experimental parameters and extension of the method to nonionic surfactants is proposed. The spectrophotometric detection, monitoring the spectral changes of a micelle-solubilized dye, is envisaged. A simple model, taking into account the global kinetics of the processes, is exposed, and, to illustrate the equations proposed and to discuss the feasibility of the method, some theoretical curves are presented.