B01D2325/22

Perfluoropolymer hollow fiber composite membrane preparation method

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.

MIXED MATRIX MEMBRANES, AND RELATED GAS SEPARATION MEMBRANE APPARATUSES, GASEOUS FLUID TREATMENT SYSTEMS, AND METHODS

A mixed matrix membrane comprises a support structure. The support structure comprises a glassy polymer matrix, and nanodiamond particles dispersed within the glassy polymer matrix. A gas separation membrane apparatus, a gaseous fluid treatment system, and a method of forming a mixed matrix membrane are also described.

MEMBRANE FOR WATER PURIFICATION
20210179450 · 2021-06-17 ·

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.

ULTRATHIN-FILM COMPOSITE MEMBRANE BASED ON THERMALLY REARRANGED POLY(BENZOXAZOLE-IMIDE) COPOLYMER, AND PRODUCTION METHOD THEREFOR

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.

MICROLAYER MEMBRANES, BATTERY SEPARATORS, BATTERIES, AND RELATED METHODS

Described herein is a multilayer microporous film or membrane that may exhibit improved properties, including improved dielectric break down and strength, compared to prior monolayer or tri-layer microporous membranes of the same thickness. The preferred multilayer microporous membrane comprises microlayers and one or more lamination interfaces or barriers. Also disclosed is a battery separator or battery comprising one or more of the multilayer microporous films or membranes. The inventive battery and battery separator is preferably safer and more robust than batteries and battery separators using prior monolayer and tri-layer microporous membranes. Also, described herein is a method for making the multilayer microporous separators, membranes or films described herein.

Filter element with improved testability after dry steaming

The present invention relates to a melt-joined filter element with improved testability after dry steaming or alternatively after sterilization by irradiation, to a method for producing the filter element according to the invention, and to the use of the filter element for filtering solutions.

Porous air permeable polytetrafluoroethylene composites with improved mechanical and thermal properties

Porous air permeable expanded PTFE composite with enhanced mechanical and thermal properties are described. The node and fibril microstructure of expanded PTFE is coated on and within the node and fibril microstructure with a suitably chosen polymer to impart property enhancement while maintaining porosity. The coating polymer content of the composite is maintained between 3 and 25 weight percent of the composite and the areal mass of the composite is less than 75 gm/m.sup.2. Exemplary enhancement to properties may include, among others, Average Tensile Strength (ATS) (in MPa)×Z strength (in MPa) of 50 MPa.sup.2 or greater, preferably 100 MPa.sup.2 or greater, with air flow less than 500 Gurley seconds. Coating polymers with appropriate temperature resistance provides composites which further exhibit shrinkage of less than 10% at temperatures up to 300° C. with air flow of less than 500 Gurley seconds.

AMMONIA SEPARATION METHOD AND ZEOLITE

Provided is a method for separating ammonia gas using zeolite membrane having excellent separation stability at a high temperature capable of separating ammonia gas from a mixed gas composed of multiple components including ammonia gas, hydrogen gas, and nitrogen gas to the permeation side with high selectivity and high permeability. Also provided is a method for separating ammonia by selectively permeating ammonia gas from a mixed gas containing at least ammonia gas, hydrogen gas, and nitrogen gas using a zeolite membrane, wherein the ammonia gas concentration in the mixed gas is 1.0% by volume or more.

FLAT SHEET POROUS MEMBRANE
20210138408 · 2021-05-13 ·

The disclosed technology relates to flat sheet porous membranes prepared from a dope solution containing a polymer of vinyl chloride, such as chlorinated polyvinyl chloride.

Aromatic co-polyimide gas separation membranes derived from 6FDA-6FpDA-type homo-polyimides

Co-polyimide membranes for separating components of sour natural gas including at least three distinct moieties polymerized together, the moieties including a 2,2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) based moiety; a 4,4′-(hexafluoroisopropylidene)dianiline (6FpDA) based moiety; and at least one component selected from the group consisting of: a 9,9-bis(4-aminophenyl) fluorene (CARDO) based moiety; a 2,3,5,6-tetramethyl-1,4-phenylenediamine (durene diamine) based moiety; a 2,2′-bis(trifluoromethyl)benzidine (ABL-21) based moiety; a 3,3′-dihydroxybenzidine based moiety; and a 3,3′-(hexafluoroisopropylidene)dianiline based moiety.