The flow of concentrated surfactant solutions through narrow capillaries

The resistance of microfilters in a flow of micellar solutions indicates that the surfactant which is adsorbed in the pores forms a mobile admicelle. The flow in these admicelles can be stopped by Marangoni forces if there is a concentration gradient of surfactant across the filter. On the basis of thermodynamic concepts and experimental data it is argued that the resistance of the filters could be affected by shear-induced surfactant adsorption. To minimize the entropy production in the flow through a narrow pore the micellar solution separates into parallel fluxes of liquid through the lumen of the pore and of mobile surfactant in the flowing admicelle.