Streaming current monitoring as a new approach for early detection of membrane wetting

Abstract

Wetting detection has emerged as a crucial topic of research for enhancing separation processes utilizing membrane contactors. In this letter, we show for the first time how streaming current measurements, via the electrokinetic leakage phenomenon, can provide a new approach to early detection of wetting of hydrophobic porous membranes. Using Tween 20 surfactant solutions of various concentrations (0.0005 – 0.07 mM) and two polyvinylidene fluoride membranes with different pore size (0.22 and 0.45 µm), we demonstrate that wetting is associated with the appearance of an electrokinetic leakage through the porosity of the membrane material, leading to an increase in the streaming current measured experimentally. Monitoring the streaming current over time therefore makes it possible to quantify the wetting kinetics of hydrophobic membranes.