A composite membrane suitable for separating a gas from a gas mixture comprising a selective layer coated on a support, wherein said selective layer comprises: a) a polymeric matrix comprising an amine polymer; b) a graphene oxide nanofiller; and c) a mobile carrier selected from an ionic liquid or an amino acid salt.

The disclosure provides a solvent resistant polyimide/polyethyleneimine@titanium dioxide nanohybrid ultrafiltration membrane with high solvent permeability and a preparation method thereof. The preparation method comprises the following steps: dissolving a titanium dioxide precursor Ti-BALDH and polyimide into N-methylpyrrolidone to prepare a casting solution, then coating on the non-woven fabric, and preparing the solvent resistant nanohybrid polyimide membrane in one step through a non-solvent induced phase separation-interface crosslinking-in-situ biomimetic mineralization coupling method. According to the disclosure, a solvent resistant polyimide/polyethyleneimine@TiO.sub.2 nanohybrid ultrafiltration membrane (PEIPI@TiO.sub.2) with high solvent permeability prepared through a simple non-solvent induced phase separation-interface chemical crosslinking-in-situ bionic mineralization coupling method.

A highly permeable sorbent platform based on polysulfone and polystyrene-b-poly(acrylic acid) composite membranes. The membranes possess a fully interconnected network of poly(acrylic acid)-lined pores, which enables the surface chemistry to be tailored through sequential attachment of polyethyleneimine moieties and metal-binding terpyridine ligands. The polyethyleneimine moieties increase the saturation capacity, while the addition of terpyridine enables high-affinity binding to a diversity of transition metal ions. This membrane platform removes such metal contaminants from solution. The metal capture performance of the functionalized membranes persists even in high concentrations of competitive ions. Also, fluorescence quenching of the terpyridine moiety upon metal ion complexation offers an in-situ probe to monitor the extent of sorbent saturation. The permeability, capacity, and affinity of these membranes, with high-density display of a metal-binding ligand, offer a chemically tailored platform to address the challenges that arise in ensuring clean water.

A selective membrane for selectively removing a metal ion from a solution. The selective membrane comprises a substrate, a polyethyleneimine layer comprising a crown ether and a cross-linker, and a polydopamine layer. A method for manufacturing a selective membrane. The method comprises contacting a substrate with polydopamine, forming a polydopamine layer on the surface of the substrate, contacting the polydopamine layer with polyethyleneimine, a cross-linker, and a crown ether, forming a polyethyleneimine layer comprising the crown ether and the cross-linker, and forming an ion channel with the crown ether. A method for selectively removing a metal ion from a solution. The method comprises contacting the solution comprising a metal with a selective membrane, applying an electric field to the selective membrane, and passing the metal ion through an ion channel.

The present invention relates to a method for producing a polyelectrolyte complex (PEC) membrane having a predetermined porosity via salt dilution induced phase separation, in which a liquid polymer solution (P) containing polyanions (A) and polycations (C) dissolved in an aqueous medium at an overcritical salt concentration is exposed to an aqueous medium.

The present disclosure relates to the research field of functionalized membrane materials and their preparation methods, in particular to a double-layer functionalized hollow fiber membrane and a preparation method thereof. The present disclosure provides a preparation method for a double-layer functionalized hollow fiber membrane, including preparation of the casting solutions, transverse extrusion casting solution, longitudinal stretching, the first coagulation bath, the second coagulation bath, and the third coagulation bath. The double-layer functionalized hollow fiber membrane prepared by the present disclosure has a double-functionalized layer structure with a dense cortical antibacterial layer and a macroporous structure adsorption layer. The double-layer functionalized hollow fiber membrane not only has the function of separation and purification, but also has the function of bacteriostasis and adsorption. The double-layer functionalized hollow fiber membrane has high strength, the wire is not easy to break, and it has a wide application field.

Provided is a gas separation membrane including: a separation layer having a function of selecting and separating carbon dioxide; and a support layer disposed on the side opposite to the space side to which a mixed gas is supplied and containing an organopolysiloxane; wherein when the layer thickness of the separation layer is tA [nm] and the layer thickness of the support layer is tB [nm], the separation layer and the support layer satisfy the following formulas (1) and (2), and when the separation layer is subjected to X-ray photoelectron spectroscopy to obtain an XPS spectrum and the C1s peak is subjected to waveform separation, the intensity ratio I (CN)/I (CC) satisfies the following formula (3).

[00001]$\begin{array}{cc}1<\mathrm{tA}+\mathrm{tB}<1000& \left(1\right)\end{array}$$\begin{array}{cc}0.01<\mathrm{tA}/\mathrm{tB}<0.20& \left(2\right)\end{array}$$\begin{array}{cc}0.03<I\left(C-N\right)/I\left(C-C\right)<0.5& \left(3\right)\end{array}$

Embodiments of the present disclosure generally relate to gas separation membranes which have one or more selective layers, methods for preparing such membranes, and methods for separating gases with such membranes. The gas separation membranes are capable of permeating one gas component selectively to a low-pressure or low-concentration permeate side at a greater transport rate than other gas components. In one or more embodiments, a separation membrane is provided and includes a non-woven fabric backing, a porous support layer disposed on the non-woven fabric backing, a gutter layer disposed on the porous support layer, and one or more selective layers disposed on or above the gutter layer. Each of the selective layers independently contains a selective polymeric material, and at least one of the selective layers contains an ethylene vinyl alcohol polymeric material as the selective polymeric material.