A monovalent selective ion exchange membrane is disclosed. The membrane includes a polymeric microporous substrate, a cross-linked ion-transferring polymeric layer on a surface of the substrate, and a charged functionalizing layer covalently bound to the ion-transferring layer by an acrylic group. A method of producing a monovalent selective cation exchange membrane is also disclosed. The method may include chemically adsorbing an acrylic intermediate layer comprising a chlorosulfonated methacrylate group to a cross-linked ion-transferring polymeric layer on a surface of a polymeric microporous substrate, aminating the chlorosulfonated methacrylate group to attach an amine group layer, and functionalizing the amine group layer with a charged compound layer to produce the cation exchange membrane. Water treatment systems including the monovalent selective cation exchange membrane and methods of facilitating water treatment including providing the monovalent selective cation exchange membrane are also disclosed.

A separation membrane suitably for water separation. The membrane includes a porous substrate layer and an active layer arranged over at least a part of the substrate layer. The active layer includes a lamellar structure comprising at least two layers of treated two-dimensional material.

The present disclosure describes membrane compositions and methods for preparing membrane compositions. In particular, the methods employ a layer-by-layer approach to membrane preparation. The membrane compositions provide significantly enhanced membrane performance over existing commercial membranes, particularly in terms of permeability and selectivity.

The present invention relates to a spiral-wound filter module exhibiting almost no heavy metal leaching and a manufacturing method thereof, and specifically, to a spiral-wound filter module, which can be used as a filter for producing safe drinking water by substantially reducing the amount of a heavy metal leached when immersed in water, and a manufacturing method thereof.

The present disclosure provides an ion-exchange membrane that includes a supporting substrate impregnated with an ion-exchange material. The supporting substrate includes an imprinted non-woven layer, and the imprinting includes a plurality of deformations at a surface density of at least 16 per cm.sup.2. The supporting substrate may lack a reinforcing layer. In some examples, the supporting substrate may include only a single layer of the imprinted non-woven fabric.

The present invention relates to a composite membrane for gas separation and/or nanofiltration of a feed stream solution comprising a solvent and dissolved solutes and showing preferential rejection of the solutes. The composite membrane comprises a separating layer with intrinsic microporosity. The separating layer is suitably formed by interfacial polymerisation on a support membrane. Suitably, at least one of the monomers used in the interfacial polymerisation reaction should possess concavity, resulting in a network polymer with interconnected nanopores and a membrane with enhanced permeability. The support membrane may be optionally impregnated with a conditioning agent and may be optionally stable in organic solvents, particularly in polar aprotic solvents. The top layer of the composite membrane is optionally capped with functional groups to change the surface chemistry. The composite membrane may be cured in the oven to enhance rejection. Finally, the composite membrane may be treated with an activating solvent prior to nanofiltration.

Embodiments disclosed herein are directed to membranes for filtration, methods of manufacturing the same, and membrane modules incorporating the same. In an embodiment, a membrane is disclosed. The membrane includes a porous cellulose layer, a polyamide thin film layer bonded to the porous cellulose layer, and a fabric support layer that supports the porous cellulose layer and the polyamide thin film layer. The porous cellulose layer has a pore size of about 30 nm to about 500 nm at an exposed surface of the porous cellulose layer.

Disclosed herein is a gas separation section for separating a first gas from one or more other gasses in a separation device, the gas separation section comprising: a first membrane that is substantially planar; a second membrane that is substantially planar; a first substrate that has a first surface and a second surface, wherein the second surface of the first substrate is on an opposite side of the first substrate than the first surface of the first substrate; a second substrate that has a first surface and a second surface, wherein the second surface of the second substrate is on an opposite side of the second substrate than the first surface of the second substrate; and a mesh that is arranged between the second surface of the first substrate and the second surface of the second substrate; wherein: the first substrate and the second substrate are sintered plates; the first membrane is on the first surface of the first substrate; the second membrane is on the first surface of the second substrate; the first and second membranes are both permeable by at least a first gas and not permeable by one or more other gasses; the thickness of the first membrane in a direction orthogonal to the plane of the first membrane is less than 10 micrometres; and the thickness of the second membrane in a direction orthogonal to the plane of the second membrane is less than 10 micrometres. Embodiments provide an improved gas separation device over known techniques. Advantages of the separation device according to embodiments include improved performance, easy implementation, a modular design and a scalable design.

Described herein is a crosslinked graphene and biopolymer (e.g. lignin) based composite membrane that provides selective resistance for solutes while providing water permeability. The membrane may include optional additional functional additives in a crosslinked material matrix that provides enhanced salt separation from water. Methods for making such membranes, and methods of using the membranes for dehydrating or removing solutes from water are also described.

Described herein is a graphene oxide and polymer based selectively permeable element that provides selective gas, and vapor resistance for dehumidification applications. The graphene oxide is cross-linked with polyvinyl alcohol, the polymer comprises an ammonium salt polymer such as poly(diallyldimethylammonium) chloride. Also described is a selectively permeable element where the graphene may be selected from reduced graphene oxide, graphene oxide, and is also functionalized or crosslinked. Also described is a selectively permeable element where there is crosslinking between the graphene and/or the polymers to provide enhanced gas resistance with water vapor permeability. A selectively permeable device is also described that incorporates the selectively permeable element and further comprises a substrate and a protective coating, encompassing the selectively permeable element. Also described are methods for making the aforementioned selectively permeable elements and related devices.