Transport mechanisms and desalination performance of the PSF/UiO-66 thin-film composite membrane: a molecular dynamics study

A novel non-equilibrium molecular dynamics (MD) model was presented to investigate the transport mechanisms and desalination performance of thin-film composite membranes (TFC). Firstly, polyamide (PA) and polysulfone (PSF), or PSF/UiO-66 models, were constructed as active and support layers. Subsequently, feed solution and draw solutions with 0.5, 1.0, and 1.5 M salt concentrations were generated. Thirdly, these aqueous and membranes were combined to build forward osmosis (FO) models. The FO process was simulated to anatomise the membrane fouling, water flux, and salt rejection, which JAVA and MD programs were combined to calculate. The results indicated that the PA-PSF/UiO-66 membrane exhibited a stable water transport and salt rejection performance compared to the pristine PA and PA-PSF membranes. Finally, experiments and simulations were compared, and the same trends were found. Therefore, this simulation work provided significant insight in guiding the design and synthesis of the FO membrane.