A process for separating carbon dioxide from a fluid containing carbon dioxide, NO.sub.2, and at least one of oxygen, argon, and nitrogen comprises the steps of separating at least part of the fluid into a carbon dioxide enriched stream, a carbon dioxide depleted stream comprising CO.sub.2 and at least one of oxygen, argon, and nitrogen and a NO.sub.2 enriched stream and recycling said NO.sub.2 enriched stream upstream of the separation step.

The present invention offers a forward osmosis composite hollow fiber membrane module having hollow fiber bundles comprising a plurality of hollow fibers, the hollow fibers having a separation layer composed of a macromolecular polymer thin film provided on the inner surface of a microporous hollow fiber supporting membrane, wherein the membrane area of the hollow fiber bundle is at least 1 m.sup.2, and a variation coefficient for the average thickness of the separation layer in the radial direction and the lengthwise direction of the hollow fiber bundles, as calculated by a method of measuring the mass of the separation layer portion in a scanning electron microscope image of a cross section of the separation layer in the thickness direction, is 0% to 60%.

The present invention offers a forward osmosis composite hollow fiber membrane module having hollow fiber bundles comprising a plurality of hollow fibers, the hollow fibers having a separation layer composed of a macromolecular polymer thin film provided on the inner surface of a microporous hollow fiber supporting membrane, wherein the membrane area of the hollow fiber bundle is at least 1 m.sup.2, and a variation coefficient for the average thickness of the separation layer in the radial direction and the lengthwise direction of the hollow fiber bundles, as calculated by a method of measuring the mass of the separation layer portion in a scanning electron microscope image of a cross section of the separation layer in the thickness direction, is 0% to 60%.

The present invention includes a method of cleaning a membrane contactor comprising: connecting a membrane contactor having a first and a second surface, the membrane contactor being in liquid communication with a first and a second liquid circulation loop; rerouting the source of oil-containing liquid from the membrane contactor; draining the oil-containing liquid in contact with the first surface of the membrane contactor via a drain; circulating a cleaning oil over the first surface of the membrane contactor; pumping a collection fluid over the second surface of the membrane contactor; and contacting the oil-containing liquid with the first surface of the membrane contactor under pressure to maximize oil coalescence at the first surface of the membrane contactor while also circulating the collection fluid over the second surface of the membrane contactor to capture the coalesced oil.

The present invention includes a method of cleaning a membrane contactor comprising: connecting a membrane contactor having a first and a second surface, the membrane contactor being in liquid communication with a first and a second liquid circulation loop; rerouting the source of oil-containing liquid from the membrane contactor; draining the oil-containing liquid in contact with the first surface of the membrane contactor via a drain; circulating a cleaning oil over the first surface of the membrane contactor; pumping a collection fluid over the second surface of the membrane contactor; and contacting the oil-containing liquid with the first surface of the membrane contactor under pressure to maximize oil coalescence at the first surface of the membrane contactor while also circulating the collection fluid over the second surface of the membrane contactor to capture the coalesced oil.

The present invention relates to a bipolar ion exchange sheet and a manufacturing method therefor, the bipolar ion exchange sheet comprising: a cation exchange film comprising a cation adsorption sheet and a cation exchange coating layer formed on one side of the cation adsorption sheet; and an anion exchange film comprising an anion adsorption sheet and an anion exchange coating layer formed on one side of the anion adsorption sheet, wherein the cation exchange film and the anion exchange film are bonded so that the cation exchange coating layer and the anion exchange coating layer face each other.

The present invention relates to a bipolar ion exchange sheet and a manufacturing method therefor, the bipolar ion exchange sheet comprising: a cation exchange film comprising a cation adsorption sheet and a cation exchange coating layer formed on one side of the cation adsorption sheet; and an anion exchange film comprising an anion adsorption sheet and an anion exchange coating layer formed on one side of the anion adsorption sheet, wherein the cation exchange film and the anion exchange film are bonded so that the cation exchange coating layer and the anion exchange coating layer face each other.

A hemofiltration device capable of surely performing highly-efficient hemofiltration. The hemofiltration device of the present invention is adapted to be implanted in a mammalian body for filtering blood, and includes a blood flow path layer having a blood flow path, a filtrate flow path layer having a filtrate flow path disposed along the blood flow path, and a filtration membrane interposed between the blood flow path layer and the filtrate flow path layer, for filtering the blood flowing through the blood flow path. A filtrate outlet of the filtrate flow path is provided at a position closer to a blood outlet than to a blood inlet of the blood flow path. The blood inlet, blood outlet, and filtrate outlet are provided only on one side or separately on opposite sides of a main body portion in the direction in which the layers are stacked.

A hemofiltration device capable of surely performing highly-efficient hemofiltration. The hemofiltration device of the present invention is adapted to be implanted in a mammalian body for filtering blood, and includes a blood flow path layer having a blood flow path, a filtrate flow path layer having a filtrate flow path disposed along the blood flow path, and a filtration membrane interposed between the blood flow path layer and the filtrate flow path layer, for filtering the blood flowing through the blood flow path. A filtrate outlet of the filtrate flow path is provided at a position closer to a blood outlet than to a blood inlet of the blood flow path. The blood inlet, blood outlet, and filtrate outlet are provided only on one side or separately on opposite sides of a main body portion in the direction in which the layers are stacked.

The present invention provides a gel comprising a physical network formed of polymer chain crystallites interconnected by amorphous chain segments. Functionalization of the chain segments between the crystallites forms a blocky distribution of functionality along the chain whereby the functionalities are concentrated in groups consisting of one or more functionalities, separated by non-functionalized runs of crystallizable segments of the polymer. Removal of the solvent from the gels, without reducing the gel volume, forms an aerogel.