An improved method for concentrating dispersions of graphene oxide, coating a substrate with a layer of a graphene oxide solution, and producing a supported graphene membrane stabilised by controlled deoxygenation; and graphene-based membranes that demonstrate ultra-fast water transport, precise molecular sieving of gas and solvated molecules, and which show great promise as novel separation platforms.

Provided is a nanofiltration (NF) or reverse osmosis (RO) membrane made of a hard carbon film that has oil resistance and can efficiently separate not only ions in water but also dye molecules present in an organic solvent, a filtering filter, a two-layer-bonded-type filtering filter, and methods for manufacturing the same, using a nanofiltration (NF) or reverse osmosis (RO) membrane (10) made of a hard carbon film characterized by being made of a hard carbon film, having a thickness (t.sub.10) of from 5 nm to 300 nm, and having a maximum pore diameter of less than 0.86 nm.

The present invention relates to a superhydrophilic biodegradable cross linked foam membrane and a process for preparation of said foam membrane from a seaweed polysaccharides by blending with amino biopolymers/amino acids/proteins/amino compounds followed by crosslinking with a naturally occurring cross linker, genipin. The foam membrane can be used as a substitute for synthetic membrane for varied applications including membrane separation for oil-water emulsions, oil-water mixtures and other aqueous-organic mixtures under ambient conditions. These foam membranes can be recycled and reused more than three times without considerable decrease in flux rate and stability. The separation methodology of the mixtures using the foam membrane of the present invention is gravity-driven and therefore, simple and energy-efficient.

A composite nanoporous metal membrane, a method of making same, and a method of using same to filter supercritical CO.sub.2 are provided. The method of making generally includes a) providing a sintered coarse porous layer; b) applying to an outer face of the coarse porous layer second metal particles; c) sintering to form a structure comprising coarse and intermediate layers; d) applying a suspension of third metal particles; e) drying the suspension of third particles; f) pressing the dried layer of third particles; and g) sintering to form a composite nanoporous metal membrane. The composite nanoporous metal membrane generally includes: a) a sintered coarse layer; b) an intermediate layer comprising first metal particles and second metal particles joined in a sintered structure which is sintered to the coarse layer; and c) a fine layer comprising third metal particles joined in a sintered structure which is sintered to the intermediate layer.

A production system for manufacturing composite porous solid articles is provided wherein the color of such articles is monitored to confirm that the articles, which are produced by heating and compressing mixtures of poly(vinylidene fluoride) binder powder (such as Kyblock resin from Arkema) and activated carbon powder, are fully cured. Adjustments to the processing conditions are made when a region of the article appears blue (indicative of incomplete curing).

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%.

Separation of linear and branched alkane isomers via selective permeation through a composite membrane is disclosed. The separation layer in the composite membrane is fabricated from a blend of at least two different fluoropolymer compositions, A and B, in which composition A has a normal-alkane isomer permeability that is greater than composition B. Composition B has a normal alkane to branched-alkane isomer selectivity that is equal or greater than composition A. The separation layer in the composite membrane has a normal-alkane permeability that is greater than composition B and a normal-alkane to branched alkane isomer selectivity that is greater than composition A.

Methods of manufacturing ion exchange membranes and ion exchange coated electrodes are described herein. Such membranes and electrodes can be used in, for example, desalination processes.

Described embodiments include a graphene membrane film for solvent purification and related method, and a solvent purification system using same. The graphene membrane film for solvent purification is formed having a plurality of stacked graphene plate-shaped flakes, and at least one pair of the plurality of stacked graphene plate-shaped flakes comprises a physical bond or a chemical bond connecting layers. The graphene membrane film for solvent purification is produced by preparing a graphene oxide dispersion liquid by dispersing graphene oxide in distilled water; confining the graphene oxide dispersion liquid between a pair of substrates; and applying heat and pressure to the graphene oxide dispersion liquid between the substrates to perform a hydrothermal reaction to concurrently thermally reduce the graphene oxide and bind graphenes. Due to lipophilic surface property and fine pores, size exclusion separation and hydrophilic-lipophilic component separation through polarity may be realized, and thus is usable in fine chemistry fields.

Durable, porous alumina-carbon nanotube membranes and methods for making them using spark plasma sintering. Methods for removing heavy metals such as cadmium from waste water using alumina-carbon nanotube membranes.