Effect of AC Field Frequency on Membrane Colloidal Deposition and Detachment

Colloidal fouling remains an operational challenge for numerous membrane filtration processes. While various approaches exist for fouling mitigation, the use of time-periodic electric fields represents a particularly interesting, relatively unexplored one. Here, we report experimental results of colloidal deposition onto an electrically conductive membrane in the presence of AC electric fields of varying frequency. We show that fouling mitigation can be achieved in the presence of an AC electric field at a relatively low applied potential amplitude of 1 V. Moreover, an extremum in the frequency response is observed in the medium frequency range (represented by 100 Hz), where deposition is greatly reduced with slow kinetics and remains reversible, all while maintaining constant permeate flux. Our results serve as an initial, experimental proof of concept, demonstrating the potential of tuning AC fields for fouling control.