Wetsus advanced water treatment scientists Sebastian Castaño Osorio, Maarten Biesheuvel, and Ettore Virga together with WUR researcher Jouke Dykstra, described previously unexplainable behavior of cations through nanofiltration (NF) membranes.
The researchers were able to adapt mean-field theory to fit newly found discrepancies in experimental data, to better detail the transport and rejection of divalent ions. By using a Langmuir-likeequation, they could calculate the changes in membrane properties – e.g., charge density – due to the adsorption or interaction of magnesium and calcium ions in a polyamide layer that commonly is part of the nanofiltration membrane.
The scientists hope to further improve the understanding of the retention and transport of the different particles in NF membranes. When properly executed, NF can be a more energy-efficient alternative to reverse osmosis that also can prevent scaling and allow better removal of impurities, thus making NF an excellent alternative for water reclamation system.
Castaño Osorio, S., Biesheuvel, P. M., Dykstra, J. E., & Virga, E. (2022). Nanofiltration of complex mixtures: The effect of the adsorption of divalent ions on membrane retention. Desalination, 527(115552), 115552. doi:10.1016/j.desal.2022.115552