Ultra-strong polymeric hollow fiber membranes for saline dewatering and desalination

Abstract

Osmotically assisted reverse osmosis (OARO) has become an emerging membrane technology to tackle the limitations of a reverse osmosis (RO) process for water desalination. A strong membrane that can withstand a high hydraulic pressure is crucial for the OARO process. Here, we develop ultra-strong polymeric thin film composite (TFC) hollow fiber membranes with exceptionally high hydraulic burst pressures of up to 110 bar, while maintaining high pure water permeance of around 3 litre/(m2 h bar) and a NaCl rejection of about 98%. The ultra-strong TFC hollow fiber membranes are achieved mainly by tuning the concentration of the host polymer in spinning dopes and engineering the fiber dimension and morphology. The optimal TFC membranes display promising water permeance under the OR and OARO operation modes. This work may shed new light on the fabrication of ultra-strong TFC hollow fiber membranes for water treatments and desalination.

Metal-organic framework enables ultraselective polyamide membrane for desalination and water reuse

“…The escalating global water shortage motivates sustainable water resource management for supplying clean, safe, and adequate water ( 1 , 2 ). To date, reverse osmosis (RO) has become a leading technology to address the severe shortages in fresh water supply through desalination and wastewater reuse ( 3 , 4 ). Although existing polyamide (PA) RO membranes exhibit high water-salt selectivity with salt rejection beyond 99% (for seawater desalination), they remain inadequate in removing certain harmful and regulated constituents from seawater and wastewater ( 5 , 6 ).…”

Seawater Desalination by Modified Membrane Distillation: Effect of Hydrophilic Surface Modifying Macromolecules Addition into PVDF Hollow Fiber Membrane

“…However, it still reaches the minimum requirement of pore size of the MD process, which is 0.20 µm. A smaller pore size is needed to avoid wetting on the membrane or the excess penetration of feed into the membrane [4,7]. The thickness of the hollow fiber membrane was analyzed by using FESEM images and a set of FESEM instruments that can measure micro size.…”

“…As porosity is also related to the permeation performance, the desired porosity in the membrane structure is as high as possible to maximize the permeation because it reflects the capacity for the membrane to allow vapor to flow into the inner side of the membrane. The larger percentage of porosity, the higher permeate flux obtained [4]. However, membranes with high porosity have low mechanical strength, so they are prone to leakage or damage to the membrane.…”

“…MD process may be used as a substitute for conventional desalination process, for example, reverse osmosis (RO), which is commercially used these days [1,4,5]. There are some advantages of using the MD process rather than the RO process.…”

Transport properties of graphene oxide nanofiltration membranes: Electrokinetic modeling and experimental validation

“…There is intense interest in energy-efficient and versatile membrane separation processes for water treatment. [1][2][3][4][5][6][7][8][9][10] Conventional polymeric thin-film composite (TFC) membranes have had good commercial success in some desalination and resource recovery applications. Process design using these membranes has been considerably aided by membrane transport models incorporating meaningful physicochemical parameters such as solute size, pore size, diffusion activation energy, interaction free-energies, and others.…”