Breakthroughs in the fabrication of electrospun-nanofiber-supported thin film composite/nanocomposite membranes for the forward osmosis process: A review

Abstract

Research on membrane technology to provide fresh water while considering inextricably linked energy issues has resulted in remarkable accomplishments in the production of membranes, such as thin film composite (TFC) membranes, for relatively lowenergy desalination and wastewater reclamation via the forward osmosis (FO) process. Exhaustive and continuous efforts in the enlargement of TFC membranes to achieve an excellent combination of flux and selectivity have revealed a considerable need to fabricate an appropriate substrate. Electrospinning, as a cheap, scalable, and simple technique, is capable of producing electrospun mats with distinctive features. These features make electrospun nanofibers (ENs) a promising substrate for TFC-FO membranes, resulting in tremendous achievements in enhancing membrane performance. Since 2011, rapid progress has been made in applying electrospinning to fabricate ENs substrates for TFC-FO membranes. This paper reviews progress in the fabrication and modification of TFC membranes supported by ENs substrates for FO applications. The theoretical background of FO, discussing the main problems associated with the use of conventional substrates, progress in applying electrospinning to overcome these problems, including breakthrough achievements in ENs substrates for FO, the synthesis and characterization of such substrates, and a comparison of energy consumption between FO and other desalination techniques were covered.

Selection of substrate manufacturing techniques of polyamine‐based thin‐film composite membranes for forward osmosis process

“…Nanofibrous TFC‐FO membranes are however hindered by their low mechanical resistance and a risk of the PA active layer delaminating from its substrate. [ 37 ] SEM images of TFC membranes with various substrate structures are presented in Figure 4. To the best of our knowledge, there are no commercial nanofibrous TFC‐FO membranes available.…”

“…The reduction of water flux in FO is fundamentally governed by the ICP phenomenon which is closely linked to the support layer's integral structural parameter. Because of the osmotic pressure gradient across the membrane's active layer, the water in the FS migrates to the support layer where it mixes with the DS which then becomes diluted [ 37,57,58,64,80 ] and exhibit a lower osmotic pressure than the bulk DS. This reduces the osmotic pressure gradient across the active layer, therefore, lowering the water flux across the membrane.…”

Polymeric Reverse Osmosis and Forward Osmosis Membranes for Water Desalination

“…Compared to phase inversion, electrospinning is another synthesis technique that has a better control on the tortuosity structure of the membrane [56,57]. Synthesis conditions such as environment conditions, solution viscosity, flow rate of the solution, and the applied voltage can be fine-tuned to obtain the membrane with desirable structural characteristics [34,58]. For example, Song et al ( 2014) adjusted the temperature to control the thickness of nanofibers within 50-150 nm [59].…”

Sustainable Treatment of Food Industry Wastewater Using Membrane Technology: A Short Review

“…Electrospun membranes, generally termed nanofibers membranes, show great promise in water treatment applications due to their outstanding features such as high surface area, mechanical robustness, small pores, porosity, and lightweight [37]. Several studies were reported in literature for the application of electrospun nanofibers in MBRs [38,39], MF [40], UF [41], NF [42], RO [43], ED [44], MD [45], membrane contactors [46] and FO [47]. We believe that writing a short review on the applications of electrospun nanofiber membranes in the food industry wastewater treatment is essential to state the current status of the research progress and its future potential suggesting research directions for further developments.…”