A New Tangential Streaming Potential Setup for the Electrokinetic Characterization of Tubular Membranes

Non-enhanced ultrafiltration of iron(III) with commercial ceramic membranes

“…Characterisation of the surface charge of tubular ceramic membranes can be conducted without cutting or crashing the ceramic tubes [20][21][22]. However, it is also common to employ flat ceramic membranes [23,24] or cutting the membrane tubes for measuring the streaming potential [25].…”

“…It must be noted that, regardless the membrane, their charge changes from positive to negative at a pH between 4.5 and 5.0. Fievet et al [20] measured the streaming potential of a T membrane, made by the same supplier and with the same ceramic materials, having a MWCO of 1.5 kDa, using an 1 mM KCl solution for the streaming potential tests. They found that the isoelectric point was located at pH 6.…”

Analysis of the pressure-induced potential arising across selective multilayer membranes

“…Up to now applied to flat membranes, let us mention that the measurement of tangential streaming potential has been recently developed for the electrokinetic characterization of tubular membranes under conditions of turbulent flow [26]. However, the tangential technique only gives an information about the ζ-potential of the outer surface of the active layer.…”

Tangential streaming potential/current measurements for the characterization of composite membranes

“…Before discussing the experimental results, it should be mentioned that with such channel heights the values of the Reynolds number can be high and turbulent conditions can be reached. Nevertheless, the equations proposed in the theoretical part are valid whatever the flow regime since they require a linear velocity profile in the electrical double layer (EDL), which is the case even under turbulent regime provided that the EDL is included in the viscous sublayer [47]. In this study, the viscous sublayer is in the order of thousand times larger than EDL, so that a linear velocity profile can be considered.…”