3D printed polyamide membranes for desalination

Abstract

Polyamide thickness and roughness have been identified as critical properties that affect thin-film composite membrane performance for reverse osmosis. Conventional formation methodologies lack the ability to control these properties independently with high resolution or precision. An additive approach is presented that uses electrospraying to deposit monomers directly onto a substrate, where they react to form polyamide. The small droplet size coupled with low monomer concentrations result in polyamide films that are smoother and thinner than conventional polyamides, while the additive nature of the approach allows for control of thickness and roughness. Polyamide films are formed with a thickness that is controllable down to 4-nanometer increments and a roughness as low as 2 nanometers while still exhibiting good permselectivity relative to a commercial benchmarking membrane.

Toward greener membranes with 3D printing technology

“…However, the research of Chowdhury et al [12] demonstrates the promising future of low-cost 3D-printed membranes.…”

“…In 2018, Ma et al [11] introduced the first 3D printing-assisted thin film composite (TFC) membrane fabrication by electro-spraying two monomer solutions to fabricate a polyamide layer through interfacial polymerization on a polymer substrate. This approach was further developed to fabricate the first self-standing 3D-printed ultrafiltration (UF) membrane [12]. Rather than getting the advantages of interfacial polymerization such as high permselectivity properties, electro-spraying based these works are also the initials of future 3Dprinted membranes, which can utilize further approaches that can even design the pore structures through computer modeling.…”

Reduced graphene oxide–metal nanoparticle composite membranes for environmental separation and chloro-organic remediation

“…† Pure water permeability (pressurenormalized ux) of the membranes was determined for transmembrane pressure (TMP) up to 10 bar. The percentage rejections of species by the membranes were determined using eqn (1).…”

“…Membrane-based separation technologies are playing a pivotal role in addressing the challenge of the increasing need for potable water by removing organic contaminants via different exclusion mechanisms. [1][2][3][4][5][6][7] In addition to the applications in separation, a membrane platform can be utilized as a support for embedding reactive nanoparticles. Reactive membranes provide an opportunity to conduct reactions, such as heterogeneous oxidation, in a continuous mode of operation for the removal of organic contaminants.…”

Green-synthesizing Ag nanoparticles by watermelon peel extract and their application in solar-driven interfacial evaporation for seawater desalination

“…Intentionally, sustainable seawater desalination is considered as a chief means and valid approach to gain fresh water in many regions, particularly water-stressed area. At present, commercial desalination technologies mainly involve two major categories, one of which is membrane-based designs like reverse electrodialysis and reverse osmosis [4,5], and the other of which is thermal-based designs such as vapor compression distillation and multi-stage flashing [6]. Nevertheless, high energy consumption combined with costly equipment make these desalination technologies unrealistic in underdeveloped region.…”