@article{132f3f921aa843e4a4827b788c29fca2,
title = "Crosslinked polyethersulfone membranes for organic solvent nanofiltration in polar aprotic and halogenated solvents",
abstract = "Organic solvent nanofiltration is a promising and more sustainable alternative to classic separation processes in multiple industries; however, proposed materials for polymeric membranes with high solvent stability mostly utilize unique or expensive polymers, or are fabricated by complex methods. Herein, a facile method is presented to fabricate crosslinked polyethersulfone membranes with remarkable stability in halogenated and polar aprotic solvents. After preparing the membranes by the conventional non-solvent-induced phase inversion process, a multidentate aromatic amine embedded in the polysulfone underwent diazotization/dediazonization to effectively crosslink the polymer matrix. Membrane performance was easily adjusted from ultra-to nanofiltration via the polymer fraction. The performance of the crosslinked polyethersulfone nanofiltration is similar to the state-of-the-art solvent stable membranes. A weeklong filtration experiment in dimethylformamide and chloroform underlines the membranes' excellent stability. Overall, the range of solvent stability and state-of-the-art performance, combined with high accessibility and scalability, make the presented membranes an ideal platform material.",
keywords = "Crosslinking, Dediazonization, Nanofiltration, Organic solvent nanofiltration, Polysulfones, Solvent resistant membrane",
author = "Eric Ziemann and Das, {Arindam Kumar} and Paramita Manna and Revital Sharon-Gojman and Michal Sela-Adler and Charles Linder and Roni Kasher and Roy Bernstein",
note = "Funding Information: SRNF membranes can be inorganic or polymeric. Inorganic ceramic membranes show outstanding stability in organic solvents, but suffer from brittleness, sensitivity to pH extremes, and their upscaling for commercialization is challenging [12,13]. Polymeric membranes are cheaper and easier to fabricate, modularize, and upscale than inorganic membranes, but typically suffer from low chemical stability in organic solvents, particularly in polar aprotic and halogenated solvents [14]. Therefore, much effort has sought to develop polymeric SRNF membranes – as integrally skinned asymmetric or thin-film composite (TFC) membranes – that are stable in strong solvents [15,16]. For TFC membranes, the (usually) asymmetric membrane support should also be solvent resistant. Asymmetric membranes can be fabricated in a single step, e.g., the non-solvent-induced phase separation (NIPS) method, with possible post-treatment steps, e.g., thermal curing with or without a crosslinker. Crosslinked polyimide (PI; obtained by NIPS followed by a simple post-treatment step using a diamine in methanol) was one of the first polymers investigated for the development of asymmetric solvent-resistant membranes [ 17–19]; it was later developed into commercial membranes. However, the acid–base stability of PI membranes is limited [20], and PIs are relatively expensive. Over the years, many other solvent stable polymers have been investigated to develop asymmetric SRNF membranes, including polypropylene, poly(ether ether ketone), poly(ethylene terephthalate), polyacrylonitrile (PAN), and aramids (highly oriented aromatic polyamides). In addition, various approaches have been studied to improve the trade-off between selectivity and permeability for asymmetric membranes [12]: For example, fabricating membranes using polymer blends, copolymers [21], block copolymers [22], or the addition of nanoparticles to obtain mixed-matrix membranes [23]. Research on stable polymeric SRNF membranes was recently expanded to consider polymers with unique microstructures, such as polymers with intrinsic microporosity and conjugated microporous or nanocomposite membranes, including thin-film nanocomposite membranes, ultrathin nanostructured polyelectrolyte TFC membranes, TFC poly(ionic liquids) gel membranes, and mixed-matrix membranes [ 24–29], all of which have presented promising results [4,30,31].Nevertheless, most SRNF membranes suffer drawbacks, including low stability in polar aprotic solvents, relatively low solvent flux, requiring complex fabrication techniques, or are based on expensive polymers. Therefore, ongoing research aims to manufacture SRNF membranes using readily available polymers commonly used in the fabrication of membranes, namely polyarylsulfones (mainly polysulfone [PSf] and polyethersulfone [PES]), polyvinylidene difluoride (PVDF), and PAN. These polymers, especially the polyarylsulfones, show outstanding filtration performance, good mechanical stability, and durability during water filtration [32]. Moreover, they are relatively inexpensive, and can be cast using commercially available methods. However, their low stability in many solvents prevents membranes based on polyarylsulfone or PVDF from being used either as asymmetric membranes or as supports for TFC membranes [33]. Therefore, enhancing the organic solvent stability of these membranes would significantly aid the development of cost-effective SRNF membranes.This work was supported by the Israeli, Ministry of Innovation, Science & Technology, Israel Grant 3-15505 (to R.B). R.K. is thankful for partial support from the Israel Science Foundation (ISF; Grant No. 3237/19). A.K.D thanks the Jacob Blaustein Center for Scientific Cooperation for a postdoctoral fellowship. E.Z. and P.M. thank the Kreitman School of Advanced Graduate Studies for support through the Hightech, Biotech, and Chemotech and the Negev scholarship programs. The authors thank Dr. Armin Greiner of Freudenberg Filtration Technologies SE & Co KG for providing nonwoven membrane support and Dr. Natalya Froumin and Dr. Ana Millionshchick from the Ilse Katz Institute for Nanoscale Science and Technology for their help with the XPS, DSC, and TGA measurements. Funding Information: This work was supported by the Israeli, Ministry of Innovation, Science & Technology, Israel Grant 3-15505 (to R.B). R.K. is thankful for partial support from the Israel Science Foundation (ISF; Grant No. 3237/19 ). A.K.D thanks the Jacob Blaustein Center for Scientific Cooperation for a postdoctoral fellowship. E.Z. and P.M. thank the Kreitman School of Advanced Graduate Studies for support through the Hightech, Biotech, and Chemotech and the Negev scholarship programs. The authors thank Dr. Armin Greiner of Freudenberg Filtration Technologies SE & Co KG for providing nonwoven membrane support and Dr. Natalya Froumin and Dr. Ana Millionshchick from the Ilse Katz Institute for Nanoscale Science and Technology for their help with the XPS, DSC, and TGA measurements. Publisher Copyright: {\textcopyright} 2022 Elsevier B.V.",
year = "2022",
month = dec,
day = "5",
doi = "10.1016/j.memsci.2022.120963",
language = "American English",
volume = "663",
journal = "Journal of Membrane Science",
issn = "0376-7388",
publisher = "Elsevier B.V.",
}
SDG 9 Industry, Innovation, and Infrastructure