Forward osmosis membranes include an active layer and a thin support layer. A bilayer substrate including a removable backing layer may allow forward osmosis membranes with reduced supporting layer thickness to be processed on existing manufacturing lines.

A mixed matrix membrane which is porous and has a cross section resembling a sponge. The membrane includes nanoparticle fillers which are also porous. The membrane may be freestanding or supported on a substrate. Methods of making the membrane by spin casting or solvent casting are described. Methods of separating a gas/organic vapor using the membrane are described.

A carbon molecular sieve (CMS) membrane is made by pyrolyzing, to a peak pyrolysis temperature T.sub.P, a hollow fiber membrane having a polymeric sheath surrounding a polymeric core, anti-substructure collapse particles present in pores formed in the polymeric core help prevent collapse of pores formed in the hollow fiber membrane before pyrolysis. The anti-substructure collapse particles are made of a material or materials that either: i) have a glass transition temperature T.sub.G higher than T.sub.P, ii) have a melting point higher than T.sub.P, or ii) are completely thermally decomposed during said pyrolysis step at a temperature less than T.sub.P. The anti-substructure collapse particles are not soluble in a solvent used for dissolution of the polymeric material of the core.

A polyimide random copolymer has a structure represented by formula (I). A method for preparing the polyimide random copolymer, a membrane made of the polyimide random copolymer, and a method for preparing a polyimide-based hollow fiber membrane are also provided. A system for purifying helium gas and a method for purifying helium gas are related to the membrane made of the polyimide random copolymer.

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A process for producing nitrogen-rich air by feeding high temperature air at 150? C. or more to an air separation membrane module is described. After being placed at 175? C. for two hours, the air separation module exhibits a shape-retention ratio of 95% or more in one embodiment. The nitrogen-rich air can be fed to a fuel tank for an aircraft, for example.

A composite membrane comprising: a) a porous support; b) a gutter layer; and c) a discriminating layer which satisfies Formula (1): wherein: ? is <4; x is the arithmetic mean of N measurements of the thickness of the discriminating layer and has a value of between 30 and 150 nm; N is at least 100; x.sub.low.sub._.sub.meas is the thickness in nm of an individual measurement of thickness within the N measurements; x>x.sub.low.sub._.sub.meas>0; and n is the number of individual thickness measurements where x>x.sub.row.sub._.sub.meas, >0 $\begin{array}{cc}?=\frac{\stackrel{\_}{x}}{\left(N-n\right)}\left(n-\underset{i=1}{\overset{n}{.Math.}}\left(1-\frac{1}{x_{{\mathrm{low}}_{\mathrm{meas}}}}\right)\right)& \mathrm{Formula}\left(1\right)\end{array}$

The present disclosure provides systems and methods for the recovery of protein species from wet mill grain process streams. Systems and methods of the present disclosure may be integrated with a wet mill grain process to separate out protein species that may limit efficiency of the grain process and produce one or more product streams comprising these separated protein species. A feed stream may be fractionated by at least two membranes into retentate and permeate streams. Removing larger proteins through the membrane fractionation may allow previously soluble prolamin products in the permeate stream(s) to precipitate. The recovered protein species may include prolamin, such as zein from a corn grain feed.

The present invention deals with a method for obtaining membranes in the form of hollow fibers with application in the field of carbon dioxide removal from natural gas. The aforementioned membranes are obtained by means of heat treatment of polymeric membranes. In this method, polymeric membranes are obtained by a phase-inversion technique by immersion-precipitation and are subsequently subjected to a heat treatment, that is, that the membranes effectively become precursor membranes of the heat treatment. The heat treatment process involves the optimization of the heating rate, temperature, and stabilization time variables, aiming at the improvement of the transport properties of the polymeric membranes. After the heat treatment, it becomes possible to use the membranes in separation processes of gases which operate at pressures greater than 30 bar, with selectivity for carbon dioxide (CO.sub.2).

A composite membrane comprising: (A) a porous support; (B) optionally a gutter layer; (C) a first discriminating layer; (D) an outermost layer; and (E) a non-discriminating layer interposed between the first discriminating layer (C) and the outermost layer (D); wherein the outermost layer (D) is a discriminating layer comprising a polyimide polymer.

A composite membrane comprising: a) a porous support; b) a gutter layer; and c) a discriminating layer;
wherein at least 10% of the discriminating layer is intermixed with the gutter layer.