Composite polyether block amide (PEBA) copolymer tubes incorporate an ultra-thin PEBA layer that enables rapid moisture transfer and exchange through the tube. A composite PEBA film may include a porous scaffold support and may be formed or incorporated into the composite PEBA tube. A porous scaffold support may be coated or imbibed with PEBA to form a composite PEBA film. A composite PEBA film may be wrapped on a mandrel or over a porous scaffold support to form a composite PEBA tube. A film layer may be applied over a wrapped composite PEBA film to secure the layers together. The film layer by applied by dipping, spraying or painting.

Composite polyether block amide (PEBA) copolymer tubes incorporate an ultra-thin PEBA layer that enables rapid moisture transfer and exchange through the tube. A composite PEBA film may include a porous scaffold support and may be formed or incorporated into the composite PEBA tube. A porous scaffold support may be coated or imbibed with PEBA to form a composite PEBA film. A composite PEBA film may be wrapped on a mandrel or over a porous scaffold support to form a composite PEBA tube. A film layer may be applied over a wrapped composite PEBA film to secure the layers together. The film layer by applied by dipping, spraying or painting.

The gas separation membrane element contains a gas separation membrane, and a sealing portion for preventing mixture of a source gas and a specific gas permeated through a gas separation membrane. The gas separation membrane has a first porous layer including a porous membrane, and a hydrophilic resin composition layer disposed on the first porous layer. The sealing portion is a region in which a cured material of a sealant penetrates in at least the first porous layer in the gas separation membrane, and a thermal expansion coefficient A of the sealing portion and a thermal expansion coefficient B of a material forming the first porous layer satisfy a relation (I):
0.35≤A/B≤1.0  (I).

The gas separation membrane element contains a gas separation membrane, and a sealing portion for preventing mixture of a source gas and a specific gas permeated through a gas separation membrane. The gas separation membrane has a first porous layer including a porous membrane, and a hydrophilic resin composition layer disposed on the first porous layer. The sealing portion is a region in which a cured material of a sealant penetrates in at least the first porous layer in the gas separation membrane, and a thermal expansion coefficient A of the sealing portion and a thermal expansion coefficient B of a material forming the first porous layer satisfy a relation (I):
0.35≤A/B≤1.0  (I).

The invention relates to a method of determining a permeation property of hollow-fibre membranes wherein the permeation property of the hollow-fibre membrane is determined on a hollow-fibre membrane bundle which has been introduced into a housing and has terminally open hollow-fibre membranes at a first end of the hollow-fibre membrane bundle and terminally closed hollow-fibre membranes at a second end of the hollow-fibre membrane bundle. The invention more particularly relates to a method of determining the ultrafiltration rate and/or the ultrafiltration coefficient of hollow-fibre membranes.

A water purification cartridge, and water permeate tubes and end caps for use therewith, are provided. An exemplary water purification cartridge has a central core with at least a first pair of permeate water tubes disposed about a central channel and a membrane assembly wrapped around and covering the central core. The membrane assembly includes at least a first membrane structure wrapped around a first permeate water tube, thereby creating a first permeate water tube assembly, and a second membrane structure wrapped around a second permeate water tube, thereby creating a second permeate water tube assembly. The first and second membrane structures are different. In another embodiment, a water purification cartridge comprises a central core with at least a first pair of permeate water tubes and a membrane assembly wrapped around and covering the central core, with each of the permeate water tubes having a generally tear-drop cross-sectional shape.

A water purification cartridge, and water permeate tubes and end caps for use therewith, are provided. An exemplary water purification cartridge has a central core with at least a first pair of permeate water tubes disposed about a central channel and a membrane assembly wrapped around and covering the central core. The membrane assembly includes at least a first membrane structure wrapped around a first permeate water tube, thereby creating a first permeate water tube assembly, and a second membrane structure wrapped around a second permeate water tube, thereby creating a second permeate water tube assembly. The first and second membrane structures are different. In another embodiment, a water purification cartridge comprises a central core with at least a first pair of permeate water tubes and a membrane assembly wrapped around and covering the central core, with each of the permeate water tubes having a generally tear-drop cross-sectional shape.

A gas separation apparatus includes a separation membrane module including at least one gas separation membrane element in a housing, a casing for blocking external air, and a heat source unit for adjusting a temperature of a heat medium with which the casing is filled. The casing holds greater than or equal to two separation membrane modules.

A gas separation apparatus includes a separation membrane module including at least one gas separation membrane element in a housing, a casing for blocking external air, and a heat source unit for adjusting a temperature of a heat medium with which the casing is filled. The casing holds greater than or equal to two separation membrane modules.

A method of concentrating lithium containing solutions includes inputting a feed brine solution to an initial separation stage, the feed brine solution including lithium sulfate and one or more of sodium sulfate, potassium sulfate, calcium sulfate, and sodium chloride dissolved in water. In the initial separation stage, the feed brine solution is introduced to a pre-treatment membrane at a pressure that is less than the osmotic pressure of the feed brine solution. An initial permeate that passes through the pre-treatment membrane becomes the feed to a final separation stage, and an initial retentate that does not pass through the pre-treatment membrane includes a precipitate of at least one of the salts other than lithium sulfate. In the final separation stage, the initial permeate is introduced to a nanofiltration membrane at a pressure that is less than the osmotic pressure of the initial permeate. A final retentate that does not pass through the nanofiltration membrane is combined with the initial retentate to obtain a product solution having a higher concentration of dissolved lithium sulfate than the feed brine solution.