Dual‐layer membrane with hierarchical hydrophobicity and transport channels for nonpolar organic solvent nanofiltration

Abstract

Nonpolar solvent separation is widely used in petroleum, chemical, food industries, but traditional separation methods consume intensive energy. State-of-art organic solvent nanofiltration membranes require complex modifications for nonpolar solvent transport. For the first time, we propose the concurrent modification of the surface, interface and support layer of dual-layer membranes with three additives (perfluorodecylamine, fluoro substituted aromatic amine, silica nanoparticles) in a onestep cocasting process. A delamination-free dual-layer membrane was obtained with a hierarchical hydrophobicity and transport channels. The novel designed structure elevated the pure n-hexane permeance (28.75 L m −2 hr −1 bar −1) by 3 orders of magnitude with a high lecithin rejection (98.7%). This method of synergistically controlling the hierarchical structures and properties of dual-layer membranes can significantly shorten the preparation process of high-performance nonpolar solvent nanofiltration membranes.

Hyperbranched polymeric membranes for industrial water purification

“…Due to the unique benefit of designing the functionality of the two layers separately, a large number of applications for DLMs have been developed which depend on the selection of materials in each layer [ 41 ]. These applications include gas separation [ 42 ], ultrafiltration [ 43 ], nano-filtration [ 44 ], organic solvent nano-filtration [ 45 ], forward osmosis and pressure retarded osmosis [ 46 ], membrane distillation [ 47 ], pervaporation [ 48 ] and photocatalytic degradation [ 49 ].…”

Thin-Film Nanocomposite Membrane Based on Mineral Silicate Maifanite for Organic Solvent Reverse Osmosis

“…4 The resulting pore sizes range from several micrometers to state-ofthe-art sub-angstrom levels, offering excellent separation of small particles by direct pressure-driven sieving and the removal of metal ions using the Donnan effect and membrane matrix interactions. 5,6 The only potential drawback of organic solvent sieving membranes is the chemical resistance resulting from their material properties and structures in various solvents. While OSN membranes cannot effectively separate monovalent ions due to their large pores, this could be achieved by OSRO membranes.…”

“…To address this issue, conventional strategies have been integrated with advanced pressure-driven molecular sieving membrane technologies, such as organic solvent reverse osmosis (OSRO), organic solvent nanofiltration (OSN), and organic solvent ultrafiltration, as better alternatives . The resulting pore sizes range from several micrometers to state-of-the-art sub-angstrom levels, offering excellent separation of small particles by direct pressure-driven sieving and the removal of metal ions using the Donnan effect and membrane matrix interactions. , The only potential drawback of organic solvent sieving membranes is the chemical resistance resulting from their material properties and structures in various solvents. While OSN membranes cannot effectively separate monovalent ions due to their large pores, this could be achieved by OSRO membranes .…”

Enrichment of carotene from palm oil by organic solvent nanofiltration

“…Besides that, in order to have a sustainable membrane fabrication process, a green crosslinking process was also investigated, which were found to have promising improvements . Moreover, one-step membrane surface modifications by Fu et al (2021) was found to improve the permeation of nonpolar solvent while maintaining high rejections of solutes. Therefore, the encouraging performance and process development of OSN membranes have provided researchers with confidence to explore OSN implementation in various industries (Marchetti et al, 2014;Nguyen Thi et al, 2021;Szekely et al, 2014).…”