The present invention relates to polymer compositions (C) for the preparation of porous article, notably microporous membranes or hollow fibers. More particularly, the present invention relates to a process of preparing a porous article from at least one polyphenylene sulfide (PPS) polymer with an additive and at least one reinforcing filler followed by a step of shaping the article and contacting the article with water to dissolve the additive and create an interconnected pore network within the shaped article.

Ion exchange membranes obtainable by curing a composition comprising: (a) a monomer comprising an aromatic group and at least one polymerisable ethylenically unsaturated group; (b) a photoinitiator which has an absorption maximum at a wavelength longer than 380 nm when measured in one or more of the following solvents at a temperature of 23° C.: water, ethanol and toluene; and (c) at least one co-initiator.

Provided is a composition for forming a separation membrane active layer, the composition comprising a compound of the following Chemical Formula 1 and a compound of the following Chemical Formula 2, wherein a percentage (a/b) of a weight (a) of the compound of Chemical Formula 1 to a weight (b) of the compound of Chemical Formula 2 is 30% to 60%, and a pH thereof is 11 to 12.7:

##STR00001## wherein in Chemical Formulae 1 and 2: R1 to R16 are each independently —CRR′— or —NR″—. at least two of R1 to R10 are —NR″—; at least two of R11 to R16 are —NR″—; and R, R′, and R″ are each independently hydrogen or a substituted or unsubstituted alkyl group; a method for producing a separation membrane; a separation membrane; and a water treatment module.

Embodiments described herein relate generally to graphene oxide membranes for fluid filtration and more specifically to graphene oxide membranes having tunable permeability, rejection rate, and flux. Some embodiments of the graphene oxide membranes disclosed herein are characterized as having a flux of at least about 2.5×10.sup.−4 gallons per square foot per day per psi with a 1 wt % lactose solution at room temperature, and a lactose rejection rate of at least 50% with a 1 wt % lactose solution.

A filter medium including: a porous first support; nanofiber webs respectively stacked at the upper and lower parts of the first support, and made of a plurality of nanofibers of which the diameters have a standard deviation of 300 nm or less; and a porous second support interposed between the first support and the nanofiber web. The filter medium is implemented by fibers having uniform diameters, and thus is easily manufactured to have a predetermined pore diameter and simultaneously has excellent uniformity of the pore diameters, thereby having excellent filtering efficiency and being more suitable when selectively separating specific objects. Backwashing is enabled at uniform pressure during backwashing such that high cleaning power is obtained. The filter medium has excellent water permeability and excellent mechanical strength so as to minimize the shape and structural deformation and damage of the filter medium.

Disclosed herein are 2-stage membrane separation methods for capturing CO.sub.2 from a feed gas. The methods can employ two selectively permeable membranes, which may be the same or different. The selectively permeable membrane can have a carbon dioxide permeance of from 500 to 3000 GPU at 57° C. and 1 atm feed pressure and a carbon dioxide:nitrogen selectivity of from 10 to 1000 at 57° C. and 1 atm feed pressure. High pressure ratios across the membranes can be achieved by compressing the feed gas to a high pressure, by using vacuum pumps to create a lowered pressure on the permeate side of the membrane, by using a sweep stream, or a combination thereof. When a sweep stream is used, the sweep stream may include a portion of the retentate gas stream obtained from the retentate side of one or more of the membranes used.

Embodiments described herein relate generally to durable graphene oxide membranes for fluid filtration. For example, the graphene oxide membranes can be durable under high temperatures non-neutral pH, and/or high pressures. One aspect of the present disclosure relates to a filtration apparatus comprising: a support substrate, and a graphene oxide membrane disposed on the support substrate. The graphene oxide membrane has a first lactose rejection rate of at least 50% with a first 1 wt % lactose solution at room temperature. The graphene oxide membrane has a second lactose rejection rate of at least 50% with a second 1 wt % lactose solution at room temperature after the graphene oxide membrane is contacted with a solution that is at least 80° C. for a period of time.

The invention relates to a method for creating a porous film through aqueous phase separation, the method comprising: i) providing an aqueous solution comprising a responsive copolymer, and optionally a charged polymer, wherein at least one of the monomers in the responsive copolymer is a responsive monomer; ii) forming the aqueous solution into a thin layer and contacting the thin layer of aqueous solution with an aqueous coagulation solution in which the responsive copolymer is not soluble, or contacting the thin layer of aqueous solution with an aqueous coagulation solution in which a complex comprising the responsive copolymer and the charged polymer is not soluble; and iii) allowing solvent exchange between the aqueous solution and the aqueous coagulation solution to produce a porous film. The invention further relates to porous films or membranes thus obtained.

This composite semipermeable membrane is provided with: a porous supporting membrane that comprises a base and a porous supporting layer; and a separating function layer that is provided on the porous supporting layer. With respect to this composite semipermeable membrane, the standard deviation of pore radius of the separating function layer as determined by positron annihilation lifetime measurement is 0.025 nm or less.

Embodiments described herein relate generally to durable graphene oxide membranes for fluid filtration. For example, the graphene oxide membranes can be durable under high temperatures non-neutral pH, and/or high pressures. One aspect of the present disclosure relates to a filtration apparatus comprising: a support substrate, and a graphene oxide membrane disposed on the support substrate. The graphene oxide membrane has a first lactose rejection rate of at least 50% with a first 1 wt % lactose solution at room temperature. The graphene oxide membrane has a second lactose rejection rate of at least 50% with a second 1 wt % lactose solution at room temperature after the graphene oxide membrane is contacted with a solution that is at least 80° C. for a period of time.