Advances in selective and efficient aqueous separations rely on overcoming two of the most pressing challenges in membrane science: the selectivity-permeability tradeoff and fouling. Traditional membranes contain pores with a broad distribution of sizes, inhibiting precision separations based on size exclusion. An analytical model is built to investigate how membrane pore-size distribution affects the solute separation efficiency. At the module level, our analysis suggests that a notably sharper rejection vs. solute size curve can be obtained as the pore-size distribution becomes narrower. Furthermore, in the separation of mixed solutes, isoporous membranes achieve a large selectivity with minimal loss of permeability. An experimental process based on nanofabrication and directed self-assembly is used to create nearly perfect isoporous membranes with tunable nanoscale dimensions. Separation performance of these membranes is explored and compared with established transport models. To address fouling, interface engineering methods based on atomic layer deposition (ALD) are applied to achieve both passive and active anti-fouling properties.

Membrane innovations for resilient and selective separations

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.