A method for producing a nano-porous membrane with one or up to four graphene layers, pores in the membrane having an average pore size in the range of 0.2-50 or 0.3-10 nm, wherein the method involves the following steps: a) generation of a contiguous, essentially non-porous membrane with one or up to four graphene layers; b) distributed point wise defect creation in the non-porous membrane with one or up to four graphene layers by way of irradiation; c) generation and successive growth of the pores at the defects generated in step b) by thermal annealing in the gas phase, e.g. under 02 at a temperature in the range of 250° C. to less than 400° C.

The present disclosure relates to hydrophilic microporous membranes comprising a modified surface. In addition, the present disclosure relates to a process for producing such hydrophilic membranes by modification of microporous membranes with fluorinated organosilane compounds and electron beam irradiation.

The present application relates to an unsupported, permanently hydrophilic filtration membrane, and its method of formation. The membrane comprises a polymeric matrix material and a cross-linked polyoxazoline hydrophilic additive blended throughout said matrix material.

The present application relates to a multizone, unsupported, microporous, high throughput membrane. The membrane includes a first microporous zone, a second microporous zone, and a third microporous zone, where the third microporous zone is positioned between the first and second microporous zones, with the first, second, and third microporous zones being integral with one another. Further aspects of the present application include a process for making the membrane and a filtration cartridge with the membrane of the present application.

Disclosed are methods for coupling a ligand to a composite material. Covalent bonds are formed between functionalized composite materials and ligands as a ligand solution flows through or across the composite materials. The composite materials are useful as chromatographic separation media.

Described herein are water desalination membranes and methods of desalinating water. Sulfonated poly(arylene ether) polymers are also disclosed, including those comprising one or more sulfonate groups at various points along the polymer chain. The polymers may be used as at least a portion of a water desalination membrane. The polymers described herein are useful for preventing transport of aqueous ionic species (e.g., Na.sup.+ and Cl.sup.−) across a membrane made from the polymers while allowing water to pass. Chlorine-stable polymers are described, as well as polymers exhibiting good performance for rejecting monovalent cations in the presence of polyvalent cations.

A filter device includes one or more filter membranes, and a filter housing enclosing the one or more filter membranes. Each of the filter membranes includes a base membrane and a plurality of through holes.

An ion-exchange apparatus has a raw-water tank 1, a treatment tank 2, an ion exchanger 3 and a voltage applying device E. The raw-water tank 1 contains a to be treated liquid that has impurity ions. The treatment tank 2 contains a treatment material with exchange ions exchangeable with the impurity ions. The ion exchanger 3 enables the passage of the impurity ions from the raw-water tank 1 to the treatment tank 2 and the passage of the exchange ions from the treatment tank 2 to the raw-water tank 1. The voltage-applying device E applies a voltage to the ion exchanger 3.

A membrane including a polymer substrate having pore channels and a metal-organic framework disposed on the polymer substrate. Methods of producing the membrane are described. Methods of separating gases using the membrane are also provided.

Provided are a polyimide compound including a repeating unit having an aromatic diamine component having a specific structure in which a side-chain benzylic position is regioselectively brominated, a gas separation membrane having a gas separation layer containing the polyimide compound, and a gas separation module and a gas separation apparatus each having the gas separation membrane.