A method of forming a filter with uniform pore sizes includes synthesizing a moiety so as to form a plurality of like platelets having a precisely sized pore extending therethrough, distributing the plurality of like platelets about a membrane having apertures therethrough, and bonding the plurality of platelets around the apertures to form precisely sized pores through the membrane. A filtration membrane is also disclosed which provides a porous membrane having a plurality of apertures therethrough, and a plurality of platelets, wherein each platelet has a pore therethrough. The platelets are positioned over or in the apertures.

Disclosed herein are a graphene-based membrane and a method of manufacturing the same. The graphene-based membrane includes: monolayer graphene containing defects; a deposition layer disposed on the defects; and nanopores surrounded by the deposition layer. The method of manufacturing a graphene-based membrane includes forming a monolayer graphene sheet and partially forming a deposition layer on the graphene sheet.

A process for preparing a composite membrane comprising the steps: a) applying a radiation-curable composition to a porous support; b) irradiating the composition and thereby forming a gutter layer of cured polymer; and c) forming a discriminating layer on the gutter layer; wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprising epoxy groups and siloxane groups, a photoinitiator and is substantially free from mono-epoxy compounds. Composite membranes and gas separation cartridges are also claimed.

A process for preparing a composite membrane comprising the steps of: a) applying a radiation-curable composition to a porous support; b) irradiating the composition and thereby forming a layer of cured polymer of thickness 20 to 400 nm on the support; c) forming a discriminating layer on the layer of cured polymer; and d) optionally forming a protective layer on the discriminating layer; wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprises dialkylsiloxane groups. Composite membranes are also claimed.

Disclosed herein are membranes comprising: porous substrate; and two or more graphene oxide (GO) sheets disposed on the porous substrate, each GO layer comprising a plurality of GO flakes, each GO flake comprising a planar graphene structure with oxygen moieties extending therefrom, wherein the membrane, when a pressure from 10 bar to 50 bar of transmembrane pressure is applied from 1 hour to 48 hours, has an aqueous flux wherein the aqueous flux changes by 5% or less while the pressure is applied. The membranes can also include an intercalating agent disposed between the two or more GO sheets, the intercalating agent interacting with each GO sheet, wherein the intercalating agent provides a non-covalent stabilization of the two or more GO sheets. Also disclosed herein are methods of making and using the same and systems for implementing the same.

Hot melt printed spacer membrane elements offer the unique advantage of applying any pattern on the membrane surface to act as the feed spacer material. This technique also eliminates damage to the active surface of the membrane by avoiding photo curing, either UV, light or other wavelengths of energy. By printing narrow features, the bending moment at the membrane surface imparted by the printed feature will be less than the bending moment imparted by a wider printed feature, thereby minimizing damage to the sensitive membrane coating.

In one aspect, the present invention relates to a membrane material having a first surface, an opposing second surface and a thickness between the first and second surfaces; the membrane material comprising a mineral comprising a metal; and at least one channel between the first surface and the second surface, wherein the channel has a diameter of less than 1 mm.

In one aspect, the present invention relates to a system comprising the membrane material. In one aspect, the present invention relates to a method of purifying a fluid, using said systems and membrane materials.