This invention discloses a thin-film composite thin-film composite membrane that is useful for the separation of solute species in organic solvents and particularly in aggressive, high boiling-point, polar-aprotic solvents such as dimethylsulfoxide, (DMSO), N-Methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF). Thin-film composite separation performance and durability is greatly enhanced through electrostatic crosslinking of an ionomer selective layer by incorporation of a multi-valent counter-ion. The thin-film composite is resistant to contact with amines and the separation efficiency is tunable by choice of multi-valent counter-ion or through the applied pressure differential across the membrane.

The present invention relates to an acid-resistant nanomembrane with an improved flow rate and a method of producing the acid-resistant nanomembrane, and more particularly, to an acid-resistant nanomembrane with an improved flow rate, which can also be used under strong-acid and high-temperature conditions for the recovery of rare metals, valuable metals, and the like generated in a smelting process and which exhibits both excellent flow rate and excellent acid resistance, and a method of producing the acid-resistant nanomembrane.

A perfluoropolymer hollow fiber composite membrane preparation method includes the steps of (A) preparing a supporting layer of the perfluoropolymer hollow fiber composite membrane, (B) preparing a membrane casting solution, which includes obtaining a mixed solution by mixing a perfluoropolymer water dispersion emulsion, a spinning carrier and solvent, and defoaming the mixed solution at vacuum and a constant temperature, (C) preparing a nascent hollow fiber composite membrane, which includes compositing by uniformly coating the membrane casting solution on an outer surface of the supporting layer through an annular spinneret using chemical fiber concentric circle composite spinning technology, putting the supporting layer after compositing into a coagulant, solidifying and forming, and (D) drying after putting the nascent hollow fiber composite membrane to a hot air box, cleaning, sintering, and performing heat preservation. The prepared membrane has a thin wall, thermal and chemical resistance and good mechanical performance.

The present disclosure is directed to methods and systems of purifying solvents. The purified solvents can be used for cleaning a semiconductor substrate in a multistep semiconductor manufacturing process.

Fluorinated polyazoles, porous membranes made therefrom, methods of making the porous membrane, and methods of using the porous membrane for purifying water, are described. For example, the present disclosure describes fluorinated polyoxadiazoles and polytriazoles that are capable of fabricating flat sheet, hollow fiber, and electrospun porous membranes are described.

The present invention relates to an ultrathin-film composite membrane based on a thermally rearranged poly(benzoxazole-imide) copolymer and a production method therefor and to a technique for forming a porous support by means of a thermally rearranged poly(benzoxazole-imide)copolymer and then producing, on the porous support, an ultrathin-film composite membrane comprising a thin-film active layer. The ultrathin-film composite membrane produced according to the present invention has excellent thermal/chemical stability and mechanical physical properties, thus is not only capable of withstanding high operating pressure, but also capable of minimizing internal concentration polarization and thereby obtaining high water permeance and, as a result, high power density, and thus can be applied to a pressure-retarded osmosis or forward osmosis process. Further, said ultrathin-film composite membrane has excellent chemical/thermal stability against organic solvents, has superior organic solvent nano-filtration performance, particularly maintains nano-filtration performance stably even under a high-temperature organic solvent condition, and thus can be applied as an organic solvent nano-filtration membrane.

The disclosure provides for polymer membranes which comprise metal organic frameworks, methods of making therein, and methods of use thereof, including in gas separation.

Provided is a method including the steps of producing a melt-kneaded product and discharging the melt-kneaded product. In the step of producing a melt-kneaded product, a thermoplastic resin, a non-solvent and an inorganic compound are mixed and melt-kneaded, wherein the non-solvent does not uniformly dissolve the thermoplastic resin of one-quarter mass at a boiling point or 250° C., whichever is lower.

Disclosed are porous membranes including a porous support and a coating comprising a copolymer having monomeric units A and B, and optionally monomeric units C; wherein A is a halogenated vinyl monomer other than tetrafluoroethylene, a halogenated alkyl vinyl ether, or an alkene of the formula C.sub.nH.sub.2n, wherein n is 1-6; B is a perfluoro (alkyl vinyl)ether compound, a perfluoroalkyl vinyl compound, or a perfluoro alkoxyalkyl vinyl ether compound, each compound having one or more sulfonic acid groups or a salt thereof, one or more sulfonyl fluoride groups, one or more sulfonamide groups, or one or more sulfonate ester groups, and C is vinylidene fluoride. Also disclosed are methods of preparing such porous membranes and methods of treating fluids by the use of these membranes.

The present invention relates to a composite semipermeable membrane including: a porous layer; a membrane separation layer provided on the porous layer; and the porous layer contains a crystalline polymer, wherein a crystallinity of the crystalline polymer is 30% or more and 50% or less.