A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.

The present invention provides highly permeable and porous polybenzimidazole membranes, methods of making them, and their application as a high-performance membrane support for gas separation composite membranes. The polybenzimidazole membranes are bonded to a fabric substrate.

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.

The present disclosure relates to a composite membrane formed by lamination of two or more separate porous polymeric layers, as well as to a method and system for lamination. Advantageously, the resulting composite is a single layer, being difficult to separate into its component layers, yet effectively maintains the filtering capabilities of the component layers when not laminated.

An apparatus and method for transferring nanofiber structures (e.g., nanofiber films, nanofiber sheets, stacks of nanofiber grids, nanofiber films, nanofiber sheets, and combinations thereof) between various substrates are described. The techniques described use a soluble layer on a substrate that is subsequently dissolved, thus freeing the nanofiber structure from the substrate. This liquid phase techniques preserves the mechanical integrity and the purity of the nanofiber structures.

A composite material contains a nonwoven layer (i) which contains fibers formed from a first thermoplastic elastomer having meshes with a mesh size in the range from 10 to 100 μm, and a membrane layer (ii) which contains a second thermoplastic elastomer and having a layer thickness of less than 30 μm. The membrane is either pore-free (ii.1) or is porous and has pores with an average pore diameter of less than 2000 nm (ii.2). The membrane (ii) is at least partially in direct contact with the fibers of the nonwoven layer (i) and covers the mesh openings in the nonwoven layer (i) at least partially. The fibers of the first nonwoven layer (i) and the membrane (ii) in the contact area are at least partly joined to one another in an interlocking manner.

A thin micro-porous membrane sheet and filtering device using it is presented. The membrane sheet includes a thin porous metal sheet of thickness between 20 and 200 μm with a porous ceramic coating of thickness less than 25 μm on at least one of its surfaces. The porous metal sheet has mean pore sizes at micro and sub-micrometer level and has a surface substantially free of pores greater than 10 micrometers. The ceramic coating layer may be made of particles with a mean particle size in a range of 10 to 300 nm and contains certain sintering promoters. The ceramic coating is sintered with the metal sheet in non-oxidizing environment at lower temperatures than typical ceramic membranes. The thin membrane sheet is used to filter fine particulates from micrometers to nanometers from a liquid or gas stream. The thin membrane sheet may be assembled into a filter device having high surface area packing density and straight mini-flow channels.

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.

The invention provides a method of forming a membrane between a first volume of polar medium and a second volume of polar medium. In some embodiments, the method involves providing a first volume including polar medium and a second volume including polar medium which are separated from one another by an apolar medium, in which at least one of the first and second volumes has a layer including amphipathic molecules.

A porous membrane material comprising a porous membrane substrate coated with a thin, uniform coating of a metal or metal alloy. The membrane material can have high electrical conductivity. The membrane material can exhibit a very high ratio of electrical conductivity to thermal conductivity. The porous membrane substrate may be removed to form the membrane.