(584b) Functionalization of Polyether Ether Ketone/Polysulfone Membranes with 2D Nanomaterials for Water Separations

Nanofiltration is a water treatment process that has gained increasing attention due to its ability to selectively remove contaminants, low energy consumption and versatility for a variety of water treatment applications. However, the removal of emerging contaminants such as pharmaceuticals and micropollutant remains a challenge for the nanofiltration technology. There is a gap for further research to improve the overall performance of the membrane especially for contaminants that require the removal to the part per trillion (ppt) level, such as per- and polyfluoroalkyl substances (PFAS).

Previous studies have demonstrated the non-carbon-based 2D nanomaterial phosphorene could be embedded onto separations membranes to provide them with advanced catalytic functionality¹. Phosphorene has unique electronic and physicochemical properties, is non-metallic, has low toxicity along with high carrier mobility, and when it was embedded onto polysulfone (PSF) membranes, it enhanced the removal of PFAS from water². It shows high photocatalytic activity due to high light absorbance and its capacity to generate electron-hole pairs under UV light irradiation, which can participate in initiating catalytic reactions by generating reactive oxygen species for the destruction of contaminant molecules. Another 2D nanomaterial, hexagonal boron nitride (h-BN), shows distinct electronic, optical, and physicochemical properties that shows promising results in the aggregation, dissolution, and oxidative degradation potential in aquatic systems. Herein, these two 2D nanomaterials were incorporated into sulfonated poly ether ether ketone/polysulfone (SPEEK/PSF) composite membrane matrixes to tune their surface properties in order to improve the removal performance and permeation rate of the membranes. The SPEEK polymer in the composite membrane provides ion-exchange properties or water uptake ability, while the PSF imparts mechanical strength thus enhances the overall stability of the membrane. The combination of these two materials may result in a membrane that is effective in removing PFAS.

(1) Eke, J.; Mills, P. A.; Page, J. R.; Wright, G. P.; Tsyusko, O. V.; Escobar, I. C. Nanohybrid Membrane Synthesis with Phosphorene Nanoparticles: A Study of the Addition, Stability and Toxicity. Polymers 2020, 12 (7). DOI: 10.3390/polym12071555.

(2) Eke, J.; Banks, L.; Mottaleb, M. A.; Morris, A. J.; Tsyusko, O. V.; Escobar, I. C. Dual-Functional Phosphorene Nanocomposite Membranes for the Treatment of Perfluorinated Water: An Investigation of Perfluorooctanoic Acid Removal via Filtration Combined with Ultraviolet Irradiation or Oxygenation. Membranes 2021, 11 (1), 18