The present invention relates to a method for producing a porous monolayer polymer membrane, to a porous monolayer polymer membrane, and to the use of the polymer membrane for filtration.

Disclosed is the preparation of composite fluid separation membranes based on poly (aryl ether ketone) (PAEK) polymers with the separation layer formed by a layer-by-layer reticular synthesis. The porous PAEK substrate is semicrystalline, exhibits a mesoporous surface structure, and is surface functionalized. The separation layer formed by the hierarchical layer-by-layer process is in the form of a covalent organic network integrally linked via covalent bonds to the functional groups of the substrate. The composite separation layer may be synthesized in situ in a preformed separation device on the surface of the PAEK substrate. Device configurations include flat sheet, spiral wound, monolith, and hollow fiber configurations with the hollow fiber configuration being preferred. Hollow fibers are formed from PAEK polymers with poly (ether ether ketone) and poly (ether ketone) particularly preferred. Composite PAEK membranes of the present invention are useful for a broad range of fluid separation applications.

Disclosed is the preparation of composite membranes formed by a tailored selective chemical modification of an ultra-thin nanoporous surface layer of a semi-crystalline mesoporous poly (aryl ether ketone) membrane with graded density pore structure. The composite separation layer is synthesized in situ on the poly (aryl ether ketone) substrate surface and is covalently linked to the surface of the semi-crystalline mesoporous poly (aryl ether ketone) membrane. Hollow fiber configuration is the preferred embodiment of forming the functionalized the poly (aryl ether ketone) membranes. Composite poly (aryl ether ketone) membranes of the present invention are particularly useful for a broad range of fluid separation applications, including organic solvent ultrafiltration and nanofiltration to separate and recover active pharmaceutical ingredients.

A zeolite membrane complex includes a porous support, and a zeolite membrane formed on the support. The zeolite membrane includes a zeolite crystal phase constituted by a plurality of zeolite crystals, and a dense grain boundary phase, which is a region between the plurality of zeolite crystals. A density of at least part of the grain boundary phase is smaller than a density of the zeolite crystal phase. A width of the grain boundary phase is 2 nm or more and 10 nm or less. Accordingly, it is possible to realize high permeability and high separating performance, and high durability of the zeolite membrane.

The invention relates to the field of biomimetic membranes with artificial water channels, notably the use thereof in the context of the production and management of drinking water. The present invention relates to a biomimetic membrane with artificial water channels, the method of synthesis thereof, as well as the use thereof for desalination of brackish water and seawater, production of ultra-pure water or filtration of contaminants.

The present invention relates, in general terms, to a composite membrane for use in filtration. The present invention also relates to a method of fabricating the composite membrane, and a method of filtrating using the composite membrane as disclosed herein. The method of fabricating a composite membrane comprising contacting a perfluorinated polymer solution with a surface of a polymer layer and drying the perfluorinated polymer solution at a relative humidity of less than 20% to form a perfluorinated polymer layer physisorbed on the surface of the polymer layer.

The objective of the present invention is to provide a composite separation membrane which is excellent in not only a liquid permeable performance and a separation performance relatively but also a durability and which is particularly useful as a membrane for liquid treatment, and a method for treating a liquid by using the composite separation membrane. The composite separation membrane according to the present invention is characterized in comprising a supporting base material and a complex layer, wherein the complex layer is placed on the supporting base material, the complex layer comprises oxidized metal nanosheets, graphene oxide and an alkanolamine, and at least one of the alkanolamine is present between the oxidized metal nanosheets.

A separation membrane complex includes a porous support and a separation membrane formed on the support. The separation membrane has a small void. A small void index I.sub.k expressed by (Σ(S.sub.k.sup.1.5))/(S.sub.m.sup.1.5) and indicating the abundance ratio of small voids is higher than or equal to 10×10.sup.−15, and a large void index I.sub.p expressed by (Σ(S.sub.p.sup.2))/(S.sub.m.sup.2) and indicating the abundance ratio of large voids is lower than 200×10.sup.−22, where S.sub.m is the surface area of the separation membrane, S.sub.k is the area per small void, and S.sub.p is the area per large void. Accordingly, the separation membrane complex can achieve a high separation ratio.

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.

The forward osmosis membrane and the preparation method thereof provided by the present invention, through fully cover the support mesh layer of the membrane with antibacterial nanoparticles, especially the mixture of nano-Ag and nano TiO2, ensures without reducing the strength, water flux and salt rejection, providing an effective, long-term and comprehensive antibacterial effect. In the present invention, the antibacterial nanoparticles, especially the mixture of nano-Ag and nano-TiO2, are used to carry out antibacterial modification on the support mesh of the forward osmosis membrane, so as to inhibit the growth of bacteria on the forward osmosis membrane, improves the forward osmosis and also improves the safety of the entire purification and filtration system. The antibacterial forward osmosis membrane of the present invention can be applied to the filtration and purification of complex water sources, especially the purification and filtration of eutrophic and bacteria-prone water sources.