Tuning the molecular structure, separation performance and interfacial properties of poly(vinyl alcohol)–polysulfone interfacial composite membranes

High permeate flux of PVA/PSf thin film composite nanofiltration membrane with aluminosilicate single-walled nanotubes

“…PVA, cast to a UF support membrane, serves as a selective layer for rejection of divalent ions with notable resistance to fouling [9]. Several studies about the use of PVA membranes for reverse osmosis [10][11][12] and nanofiltration [13][14][15] have been carried out. Most of these membranes focus on enhancing the permeate flux while maintaining high selectivity by improving surface cross-linking and dip-coating methods.…”

Molecular Scale Modeling of Membrane Water Treatment Processes

“…Molecular simulations have been used in recent years to predict the water and solute transport behaviors of various PA RO membrane materials [29,34]. Collectively, these studies have clearly demonstrated the utility of this approach and molecular simulations are now being utilized more frequently in the fundamental design and engineering of novel membrane materials [34].…”

“…Collectively, these studies have clearly demonstrated the utility of this approach and molecular simulations are now being utilized more frequently in the fundamental design and engineering of novel membrane materials [34]. Molecular simulations also have the added benefit of being able to elucidate transport or rejection mechanisms that would otherwise be extremely challenging to decipher using current experimental techniques alone [27].…”

“…Several recent publications have addressed the role of the fractional free volume (FFV) on the performance (water and salt transport) of various PA membranes as determined from MD simulations [34,37,38]. The FFV is proportional to V − V 0 /V, where V is the total system (model) volume, V 0 is the specific volume CV w , where V w is the van der Waals space of the polymer and C is a proportionality constant whose value depends on the type of hard-surface probe rendering implemented (typically a Connolly surface with a probe radius of 1.3-1.6Å; Figure 10.13).…”

“…Recently, Peng et al [34] used FFVs calculated from MD simulations to estimate the water flux and salt rejection behaviors of a series of ultrathin cross-linked poly(vinyl alcohol)-polysulfone interfacial composite membranes. The free volume measurements of the nanofiltration-like membrane materials derived directly from the MD simulations strongly agreed with composite membrane permeability, including the pure water flux and rejections of sodium, chloride, and sulfate.…”