Water permeable membranes and methods of preparation are described. The water permeable membrane can comprise a porous support, and a polyamide layer comprising a crosslinked polyamide on a surface of the porous support, wherein the polyamide layer further comprises nanoparticles and a hydrophilic additive, and wherein the hydrophilic additive covalently bonds to the crosslinked polyamide. The crosslinked polyamide can be interfacially polymerized on the porous support. Methods for desalinating water, performing dialysis, or performing pervaporation using the water permeable membranes are disclosed.

A method for preparation of conductive polymer/carbon nanotube (CNT) composite nanofiltration (NF) membrane and the use thereof. This conductive polymer/CNT composite NF membrane is obtained by polymerizing conductive polymer into a CNT membrane and then in-situ cross-linking with glutaraldehyde under acidic condition. The synthetic method for the conductive polymer/CNT composite NF membrane is simple and has no need of expensive equipment. The prepared membrane has controllable membrane structure and possesses superior electrical conductivity and electrochemical stability. The membrane can couple with electrochemistry for electrically assisted filtration. With the electrical assistance, the membrane can achieve improved ion rejection performance while retaining high permeability by enhancement of membrane surface charge density, which alleviates the permeability-selectivity trade-off. Furthermore, the electrically assisted NF membrane filtration can also enhance the removal for small molecular organic pollutants.

Embodiments described herein relate generally to durable graphene oxide membranes for fluid filtration. For example, the graphene oxide membranes can be durable under high temperatures non-neutral pH, and/or high pressures. One aspect of the present disclosure relates to a filtration apparatus comprising: a support substrate, and a graphene oxide membrane disposed on the support substrate. The graphene oxide membrane has a first lactose rejection rate of at least 50% with a first 1 wt % lactose solution at room temperature. The graphene oxide membrane has a second lactose rejection rate of at least 50% with a second 1 wt % lactose solution at room temperature after the graphene oxide membrane is contacted with a solution that is at least 80° C. for a period of time.

The invention a solvent-resistant polymeric nanofiltration membrane and preparation method thereof. The method includes subjecting a diamine monomer and a dianhydride monomer to cyclization imidization in a first polar organic solvent at 160 to 230° C., to form a polyimide, wherein the diamine monomer includes a diamine monomer with a carboxyl group and a diamine monomer without a carboxyl group; dissolving the polyimide in a second polar organic solvent, to form a membrane-forming solution; performing phase inversion to obtain an intermediate membrane; treating the intermediate membrane with an organic solution of a metal salt, so that the metal ion is coordinated and cross-linked with the carboxyl group in the polyimide, to obtain a solvent-resistant polymeric nanofiltration membrane, wherein the metal salt is a divalent and/or a multi-valent metal salt. The invention also discloses use of the solvent-resistant polymeric nanofiltration membrane in the separation and/or purification of a compound.

New carbon nanomaterials, preferably titanium carbide-derived carbon (CDC) nanoparticles, were embedded into a polyamide film to give CDC/polyamide mixed matrix membranes by the interfacial polymerization reaction of an aliphatic diamine, e.g., piperazine, and an activated aromatic dicarboxylate, e.g., isophthaloyl chloride, supported on a sulfone-containing polymer, e.g., polysulfone (PSF), layer, which is preferably previously prepared by dry/wet phase inversion. The inventive membranes can separate CO.sub.2 (or other gases) from mixtures of CO.sub.2 and further gases, esp. CH.sub.4, based upon the generally selective nanocomposite layer(s) of CDC/polyamide.

The invention relates to the field of industrial wastewater treatment, and particularly discloses a nanofiltration membrane for treating printing and dyeing wastewater and its preparation method. The preparation method comprises the following steps: S1, pouring an aqueous solution containing m-phenylenediamine, camphorsulfonic acid and triethylamine onto the surface of a polysulfone ultrafiltration membrane, setting still for 10 s to 30 s, and then removing the excess aqueous solution from the surface; S2, pouring an organic solution containing trimesoyl chloride and an interface auxiliary polymerization agent onto the surface of the membrane obtained in step S1, reacting for 5 s to 20 s, and then removing the excess solution from the surface; and S3, setting the membrane obtained in step S2 still and then carrying out heat treatment and water rinsing on the membrane in sequence, thus obtaining the nanofiltration membrane.

A method for preparing a durably hydrophilic and uniform-pore ultrafiltration membrane is disclosed herein. Chemical reactions between the functional groups and the active bonds of the molecular chains in the membrane materials are initiated perform the grafting of hydrophilic chains on the polymer chains under conventional dissolution conditions of the polymer membrane material (dissolution with synchronized hydrophilization), so as to realize durable hydrophilization of the membrane materials. The resulting hydrophilized polymer solution (a nascent-state membrane) is introduced into a coagulation bath to initiate a crosslinking reaction among the hydrophilic chains. The resulting crosslinking serves to synergistically regulate subsequent phase separation and membrane formation (phase separation under synergistic crosslinking).

The present invention relates to a process for the preparation of a polyarylene ether sulfone polymer (P) by converting a reaction mixture (R.sub.G) which comprises, among others, at least one aromatic dihalogen sulfone and at least one dihydroxy component comprising at least 20 mol-% of trimethylhydroquinone based on the total amount of the at least one dihydroxy component. The present invention furthermore relates to the Ouse of a polyarylene ether sulfone polymer (P) obtainable by the inventive process in a membrane (M) and to a membrane (M) comprising the polyarylene ether sulfone polymer (P) obtainable by the inventive process, as well as to a method for the preparation of a membrane (M).

The present disclosure relates to a method of preparing a thin film composite layer immobilizing vesicles incorporating a transmembrane protein on a porous substrate membrane, comprising providing an aqueous solution comprising the vesicles and a di-amine or tri-amine compound, covering the surface of a porous support membrane with the aqueous solution, applying a hydrophobic solution comprising an acyl halide compound, and allowing the aqueous solution and the hydrophobic solution to perform an interfacial polymerization reaction to form the thin film composite layer.

A method for preparing a nanofiltration membrane and a nanofiltration membrane prepared therefrom, the method comprising the following steps: dissolving a polymer in a solvent to prepare a polymer solution, and curing the polymer solution on a support material to form a base membrane; sequentially applying a first liquid-phase solution and a second liquid-phase solution on the base membrane to form a nascent membrane; densifying the nascent membrane by using a solution that contains an alkaline substance; processing the densified nascent membrane by using a solution that contains an acidic substance; and obtaining the nanofiltration membrane after post-processing and drying.