B01D2325/24

CROSSLINKED POLYMER MEMBRANES AND METHODS OF THEIR PRODUCTION
20210170345 · 2021-06-10 ·

Described in the present application are methods of producing silane-crosslinked polymer membranes at moderate temperatures using acid catalysts that, in certain embodiments, result in membranes with unexpectedly high permeabilities and selectivities. In certain embodiments, grafting and crosslinking of the silanes occur by immersing a preformed membrane in a solution comprising a silane and an acid catalyst. Alternatively, in certain embodiments, grafting of silanes to a polymer occurs in the presence of acid catalyst in solution and subsequent casting and drying produces crosslinked membranes. In certain embodiments, an acid catalyst is a weak acid catalyst. Also described in the present application are asymmetric crosslinked polymer membranes with porous layers. In certain embodiments, crosslinked cellulose acetate membranes have permeability up to an order of magnitude greater than the permeability of unmodified cellulose acetate membranes. The membranes have porous layers with a high porosity due to their processing in moderate conditions.

Porous hollow fiber membrane, method for producing porous hollow fiber membrane and filtration method
11110402 · 2021-09-07 · ·

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.

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.

CERAMIC CATION EXCHANGE MATERIALS

Cation exchange membranes and materials including silica-based ceramics, and associated methods, are provided. In some aspects, cation exchange membranes that include a silica-based ceramic that forms a coating on and/or within a porous support membrane are described. The cation exchange membranes and materials may have certain structural or chemical attributes (e.g., pore size/distribution, chemical functionalization) that, alone or in combination, can result in advantageous performance characteristics in any of a variety of applications for which selective transport of positively charged ions through membranes/materials is desired. In some embodiments, the silica-based ceramic contains relatively small pores (e.g., substantially spherical nanopores) that may contribute to some such advantageous properties. In some embodiments, the cation exchange membrane or material includes sulfonate and/or sulfonic acid groups covalently bound to the silica-based ceramic.

Forward Osmosis Membrane and Membrane Module Including Same

Provided are a composite forward osmosis membrane and a membrane module containing same. The composite forward osmosis membrane reduces salt back-diffusion and has high water-permeability, or is made of readily available materials and can be easily manufactured. Even when used at high pressure, separation between a substrate membrane support layer and an active separation layer does not occur in the composite forward osmosis membrane, and thus the composite forward osmosis membrane exhibits stable high performance.

Separation membrane sheet, separation membrane element, separation membrane module, and manufacturing method for separation membrane sheet

A separation membrane sheet that causes a specific fluid component to selectively permeate therethrough, comprises: a first porous layer; and a resin composition layer formed on the first porous layer. The resin composition layer has a filtration residue fraction of greater than or equal to 20% and less than or equal to 90%; and contains a resin having an ionic group or a salt thereof, and has an ion exchange capacity of greater than or equal to 1 millimole equivalent per 1 g of a dry resin in a filtration residue.

Process and device for converting hydrogen sulfide into hydrogen gas and sulfur

A reactive process for converting hydrogen sulfide into hydrogen gas and sulfur and a reactor for effecting such process.

COMPOSITE SEMIPERMEABLE MEMBRANE
20210197137 · 2021-07-01 ·

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.

COMPOSITE SEMIPERMEABLE MEMBRANE
20210197138 · 2021-07-01 ·

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 polymer, the polymer containing one of either a fluoropolymer or an imide group-containing polymer, wherein a compression ratio of a portion including the porous layer and the membrane separation layer when subjected to a pressure of 5.5 MPa is 60% or less.

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.