The present invention relates to a method of preparing a nanocomposite membrane, comprising: (a) providing a nanocomposite solution comprising a polymer solution and nanomaterials; (b) subjecting the nanocomposite solution to a cold water bath to produce the nanocomposite membrane in a gel-like form; and (c) subjecting the gel nanocomposite membrane to a heat treatment to solidify the nanocomposite membrane, wherein the nanomaterials are dispersed within the polymer matrix of the nanocomposite membrane.

Provided is a water treatment membrane including: a porous support; and a polyamide active layer provided on the porous support, in which the polyamide active layer includes one or more units selected from among a unit of Chemical Formula 1:

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a unit of Chemical Formula 2;

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a unit of Chemical Formula 3;

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and a unit of Chemical Formula 4;

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and a manufacturing method thereof.

A sheet filter membrane is arranged on a surface of a filter plate of a thermoplastic resin, and a plurality of projections provided in a hot plate is pressed against the filter plate above a periphery of the filter membrane with different timing for each of the projections to abut on the filter membrane. A plurality of recessed bonding portions with different depths are thus formed in the filter plate, and the filter membrane is bonded to the filter plate by heat welding in each of the recessed bonding portions. Sealing is therefore provided between the filter membrane and the filter plate along the periphery of the filter membrane.

The invention, belonging to the field of membrane technology, presents a method for the direct growth of ultrathin porous graphene separation membranes. Etching agent, organic solvent and polymer are coated on metal foil, and then they are calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. Alternatively, the dispersion or solution of etching agent is coated on metal foil, on which a polymer film is then overlaid. The obtained sample is subsequently calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. The method involved in this invention is simple and highly efficient, and allows direct growth of ultrathin porous graphene separation membranes, without needing expensive apparatuses, chemicals and graphene raw material. Additionally, the graphene membranes prepared with this method have controlled pore size, ultrahigh water flux and strong resistance to irreversible fouling.

Stabilized surfactant-based membranes and methods of manufacture thereof. Membranes comprising a stabilized surfactant mesostructure on a porous support may be used for various separations, including reverse osmosis and forward osmosis. The membranes are stabilized after evaporation of solvents; in some embodiments no removal of the surfactant is required. The surfactant solution may or may not comprise a hydrophilic compound such as an acid or base. The surface of the porous support is preferably modified prior to formation of the stabilized surfactant mesostructure. The membrane is sufficiently stable to be utilized in commercial separations devices such as spiral wound modules. Also a stabilized surfactant mesostructure coating for a porous material and filters made therefrom. The coating can simultaneously improve both the permeability and the filtration characteristics of the porous material.

To make membranes, a plurality of membrane substrates are each wetted with a curable liquid mixture, arranged in a stack such that every pair of substrates are separated by at least one film, and moved simultaneously through a common curing region. Each wetted substrate sheet may be sandwiched between two films. After curing, the stack comprises two or more membranes with each pair of membranes separated by a film. An apparatus for making membranes comprises at least two substrate feeding devices, at least one film feeding device, one or more chemical wetting devices, a curing region, optionally, a stack separating region, and, optionally, a membrane binding or fusing region. Membrane production rate may be increased while the curing energy required per unit area of membrane is decreased. The method can make, for example, ion exchange membranes.

This invention provides a new high selectivity stable facilitated transport membrane comprising a polyethersulfone (PES)/polyethylene oxide-polysilsesquioxane (PEO-Si) blend support membrane, a hydrophilic polymer inside the pores on the skin layer surface of the PES/PEO-Si blend support membrane; a hydrophilic polymer coated on the skin layer surface of the PES/PEO-Si blend support membrane, and metal salts incorporated in the hydrophilic polymer coating layer and the skin layer surface pores of the PES/PEO-Si blend support membrane, and methods of making such membranes. This invention also provides a method of using the high selectivity stable facilitated transport membrane comprising PES/PEO-Si blend support membrane for olefin/paraffin separations such as propylene/propane and ethylene/ethane separations.

Provided is a post-formation process for preparation of a highly permeable thin film composite membranes for reverse osmosis, particularly for use with brackish water at low energy conditions. The process includes contacting a polyamide discrimination layer of a TFC membrane with a solution containing an oxidizing agent to form a treated membrane, followed by contacting the treated membrane with a solution containing a reducing agent. The resulting membrane exhibits enhanced water flux while maintaining salt rejection. Also provided are reverse osmosis membranes prepared in accord with the method, and modules containing the highly permeable thin film composite membranes, and methods of purifying water using the membranes or modules.

Ultra-thin nanometer-sealer freestanding polymeric membranes and methods for producing ultra-thin nanometer-scale freestanding recast membranes and ultra-thin nanometer-scale freestanding cross-linked membranes with solid internal backbone are disclosed.

A method for the manufacture of a carbon nanomembrane is disclosed. The method comprises preparing a metallised polymer substrate and applying on the metallised polymer substrate a monolayer prepared from an aromatic molecule. The aromatic molecule is cross-linked to form a carbon nanomembrane. The carbon nanomembrane is coated by a protective layer and subsequently the carbon nanomembrane and the protective layer are released from the metallised polymer substrate. Finally, the carbon nanomembrane and the protective layer are optionally placed on a support. The protective layer can be optionally removed. The carbon nanomembrane can be used for filtration.