The disclosure of the present invention relates to a method for preparing membrane and associated membrane and filter element. The method comprises providing a porous substrate having a plurality of pores; and applying a pre-filler solution to at least partially occupy the pores in the porous substrate. The membrane comprises a porous substrate and a filter layer formed on the porous substrate. The filter element comprises a core tube; and a membrane as prepared and rolled around the core tube.

Polymer-based membranes and methods for fabricating membranes are described. The methods include forming a casting solution featuring a plurality of titanium dioxide (TiO2) nanoparticles, a polyvinylidene fluoride (PVDF)-based solvent, and a polyvinylpyrrolidone (PVP)-based modifying agent, dispersing the casting solution to form a first element, generating a plurality of active sites on a surface of the first element, and forming a polymer-based membrane by exposing the surface of the first element to a fluorosilane composition to form a fluorosilane layer on the surface, where the fluorosilane composition includes a silane compound having at least one alkyl substituent that includes between 9 and 21 fluorine atoms.

The invention provides systems and methods for substantially improving the compaction resistance of isoporous block copolymer (BCP) film by adding a high molecular weight hydrophilic additive in the casting dope formulation. Systems and methods disclosed also disclose several other multifunctional enhancements to film properties including: low fouling propensity, improved permeability, improved permeability retention upon drying, and ability to tune the substructure and pore size of these novel BCP films. These porous BCP films are useful in filtration and separations applications and are amenable to standard manufacturing practices.

The invention provides systems and methods for substantially improving the compaction resistance of isoporous block copolymer (BCP) film by adding a high molecular weight hydrophilic additive in the casting dope formulation. Systems and methods disclosed also disclose several other multifunctional enhancements to film properties including: low fouling propensity, improved permeability, improved permeability retention upon drying, and ability to tune the substructure and pore size of these novel BCP films. These porous BCP films are useful in filtration and separations applications and are amenable to standard manufacturing practices.

The present disclosure relates to a microporous hollow fiber filter membrane having a large inner diameter and a thin wall. The fiber can be used for sterile filtration of liquids or removal of particles from liquids. The disclosure further relates to a method for producing the membrane and a filter device comprising the membrane.

The invention provides a continuous preparation method of 2,3,3,3-tetrafluoropropene, comprising the following steps: carrying out liquid-phase catalytic telomerization reaction on ethylene and carbon tetrachloride serving as initial raw materials in the presence of a composite catalyst to obtain a reaction product; performing two-stage membrane separation and purification on the reaction product, and then sequentially performing a primary high-temperature cracking reaction, a gas-phase chlorination reaction, a secondary high-temperature cracking reaction, a primary gas-phase catalytic fluorination reaction and a secondary gas-phase catalytic fluorination reaction to obtain a reaction product; condensing and rectifying the secondary gas-phase catalytic fluorination reaction product to obtain the 2,3,3,3-tetrafluoropropene product.

A preparation method of an antifouling and hydrophilic polyethersulfone ultrafiltration membrane includes through the .sup.60Co-γ radiation grafting chemical modification method, evenly distributing an ionic liquid on a surface of a polyethersulfone material, wherein the ionic liquid containing unsaturated bonds is connected with the polyethersulfone material through chemical bonds, and then obtaining an asymmetric porous membrane by the immersion-precipitation phase transformation method, and finally performing Soxhlet extraction on the porous membrane, so as to migrate the grafted ionic liquid from an interior of the porous membrane to a surface of the porous membrane to be enriched, so that the adsorption and antibacterial properties of the porous membrane are improved. A mass ratio of the ionic liquid to the polyethersulfone material is in a range of (2-11):100. The ultrafiltration membrane is an asymmetric porous membrane, and has excellent antifouling properties, good pure water flux and a good BSA retention rate.

A hollow fiber membrane for removal of dissolved oxygen from fluid that is made of a porous hydrophobic material and an apparatus for controlling nitrate concentration level in water comprising a membrane contactor having the membrane, the membrane comprises at least one tubular fiber comprising: an outer wall for contacting fluid external to the tubular fiber; at least three inner channel walls for contacting fluid internal of the tubular fiber, wherein each inner channel wall forms a fluid communicating channel; a plurality of pores, wherein pores proximate to surfaces of the outer wall and each inner channel wall are smaller in size than pores non-proximate to said surfaces of the outer wall and each inner channel wall, wherein a central portion of the tubular fiber has a thickness greater than thickness of the tubular fiber outside the central portion.

A method for making a gas separation membrane comprises dissolving and mixing poly(ether-b-amide) (Pebax) copolymer and acrylate-terminated polyethylene glycol oligomers (PEGDA) in a solvent, casting the polymer solution into a mold, removing the solvent to form a film, adding a photoinitiator to the film and irradiating the film with ultraviolet radiation to induce crosslinking of the PEGDA in the film, producing XLPEGDA, and submerging the film after exposure in a crosslinking solution to form crosslinked Pebax (XLPebax) in the film, wherein the crosslinking solution comprises one of a diisocyanate, a diisocyanate derivative and a combination of a diiscyanate and a diisocyanate derivative.

The present invention relates to a membrane distillation system comprising a flat-sheet composite mixed matrix hydrophilic/hydrophobic membrane having at least a hydrophilic layer and a hydrophobic layer. The hydrophilic layer comprises a hydrophilic polymer and inorganic nanoparticles having high thermal conductivity. The hydrophobic layer comprises fluorinated surface-modifying macromolecules (SMM). Also disclosed is a phase inversion method for manufacturing the membrane.