[Problem] Provided is a semipermeable membrane that achieves chemical resistance (chlorine resistance, acid resistance, alkali resistance), membrane performance, and membrane strength by sulfonating a polyphenylene-based semipermeable membrane base material under specific conditions. [Solution] A polyphenylene-based semipermeable membrane that is composed of a material containing a polyphenylene-based resin, wherein the semipermeable membrane has a first surface of which at least a portion is sulfonated, and wherein, when concentration distribution of elemental sulfur derived from a sulfonic acid group is measured by elemental analysis in a cross section in a thickness direction of the semipermeable membrane, a ratio of a sulfonated layer obtained by the following expression is 50% or less: Ratio of Sulfonated Layer (%)=Sulfonated Layer Thickness/(Sulfonated Layer Thickness+Non-Sulfonated Layer Thickness)×100.

A gas separation membrane for selective separation of hydrogen and helium from gas mixtures containing carbon dioxide includes a porous support layer, an aromatic polyamide layer on the porous support layer, and a coating including a glassy polymer formed on the aromatic polyamide layer. A glass transition temperature of the glassy polymer is greater than 50° C. The gas separation membrane may be formed by contacting a solution including the glassy polymer with an aromatic polyamide layer of a composite membrane and drying the solution to form a coating of the glassy polymer on the aromatic polyamide layer. Separating hydrogen or helium from a gas stream including carbon dioxide includes contacting a gas feed stream including carbon dioxide with the gas separation membrane to yield a permeate stream having a concentration of helium or hydrogen that exceeds the concentration of helium or hydrogen, respectively, in the gas feed stream.

A composite membrane comprising a supporting membrane that includes polyphenylene oxide and a separation layer that is disposed on one main surface of the supporting membrane, wherein the poiyphenylene oxide is sulfonated on the one main surface of the supporting membrane and the separation layer includes polyvinyl alcohol having an ionic functional group.

A novel membrane is provided in which the permeate flow rate is not prone to decrease even when the membrane is used to process seawater with high salt concentration and high heavy metal ion concentration. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer coating the separation function layer, wherein the separation function layer contains a crosslinked polymer amide which is a condensate of polyfunctional aromatic amine and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer including a polyether moiety and a carbonic acid polymer moiety.

A gas separation membrane for selective separation of hydrogen and helium from gas mixtures containing carbon dioxide includes a porous support layer, an aromatic polyamide layer on the porous support layer, and a coating including a glassy polymer formed on the aromatic polyamide layer. A glass transition temperature of the glassy polymer is greater than 50 C. The gas separation membrane may be formed by contacting a solution including the glassy polymer with an aromatic polyamide layer of a composite membrane and drying the solution to form a coating of the glassy polymer on the aromatic polyamide layer. Separating hydrogen or helium from a gas stream including carbon dioxide includes contacting a gas feed stream including carbon dioxide with the gas separation membrane to yield a permeate stream having a concentration of helium or hydrogen that exceeds the concentration of helium or hydrogen, respectively, in the gas feed stream.

A gas separation membrane for selective separation of hydrogen and helium from gas mixtures containing carbon dioxide includes a porous support layer, an aromatic polyamide layer on the porous support layer, and a coating including a glassy polymer formed on the aromatic polyamide layer. A glass transition temperature of the glassy polymer is greater than 50 C. The gas separation membrane may be formed by contacting a solution including the glassy polymer with an aromatic polyamide layer of a composite membrane and drying the solution to form a coating of the glassy polymer on the aromatic polyamide layer. Separating hydrogen or helium from a gas stream including carbon dioxide includes contacting a gas feed stream including carbon dioxide with the gas separation membrane to yield a permeate stream having a concentration of helium or hydrogen that exceeds the concentration of helium or hydrogen, respectively, in the gas feed stream.

The object of the present invention is polyphenylene oxide based film with crystalline nanoporous phases with surface area equal to or greater than 30 m2/g, preferably greater than 100 m2/g, and a procedure for the attainment thereof.

A poly(phenylene ether) can be prepared by a method that includes reacting 2,6-dimethylphenol in the presence of toluene, oxygen, copper ion, bromide ion, and N,N-di-tert-butylethylenediamine to form a poly(phenylene ether). The mole ratio of 2,6-dimethylphenol to copper ion is 160:1 to 300:1, the mole ratio of N,N-di-tert-butylethylenediamine to copper ion is 1.5:1 to 3:1, and the mole ratio of atomic oxygen to 2,6-dimethylphenol is 0.9:1 to 1.5:1. The process can produce poly(phenylene ether) having a high molecular weight and a high incorporated amine content.

Disclosed herein is a process for separation and purification of a fermentation gas product from a fermenter off-gas containing a fermentation product, volatile impurities, bio-product impurities and water, based on a membrane system. In one preferred embodiment of the present invention, the process of separating and purifying a fermentation product from a fermenter off-gas, containing the fermentation product, volatile impurities, bio-byproduct impurities and water, comprises the steps of: (a) compressing the fermenter off-gas and feeding it into a membrane module, and (b) selectively permeating the volatile impurities, bio-byproduct impurities and water through the membrane, resulting in a product rich retentate stream. The fermentation gas product is separated from the fermenter off-gas in a single membrane stage to produce a purified retentate stream. In accordance with this embodiment of the invention, the fermenter off-gas (2), comprising the fermentation gas product, volatile impurities, bio-byproduct impurities and water, passes through a blower (201) that transports it to a gas holder (202), in order to smooth the process fluctuations. Stream (11) exits the gas holder (202) and is compressed in a multi-stage compressor (203), from which bio-byproduct and water are removed through stream (4). The compressed stream (12) enters the membrane module (204), which permeates the volatile impurities, disposing them in stream (13). The process may be still conducted in a 2-stage membrane system in accordance with the present invention.

A device for separating components of a gas mixture includes a hollow housing having a body portion at a first end, a separable end cap at a second end, and at least one side wall. The housing has an inlet port for the gas mixture, a permeate outlet port for gas mixture enriched with a first component of the mixture, and a retentate outlet port for gas mixture enriched with a second component of the mixture. An insert within the housing comprises a plurality of hollow fibres of a material which are more permeable to the first component than the second. The housing defines passageways for gas to flow between the inlet port and the permeate and retentate outlet ports. The insert is fastened to the end cap at least temporarily so that the insert is withdrawn from within the housing when the end cap is removed.