Provided is a method of manufacturing a multilayer mixed matrix membrane which includes providing a support layer, casting a hydrophilic layer on a surface of the support layer, casting a hydrophobic layer on the hydrophilic layer, and allowing the layers to form a multilayer mixed matrix membrane. Also provided is a method of manufacturing a hollow fiber composite matrix membrane which includes providing a first solution having a hydrophilic polymer, providing a second solution having a hydrophobic polymer, and extruding the first and second solutions to form a multilayer hollow fiber composite matrix membrane. Additionally, a plate-and-frame membrane module for direct contact membrane distillation using a multilayer mixed matrix membrane is provided. The plate-and-frame membrane module includes a feed inlet capable of distributing process solution throughout the membrane module, a permeate inlet capable of distributing process solution throughout the membrane module, a tortuous promoter comprising multiple flow channels, a feed outlet, and a permeate outlet.

Synthetic membranes for the removal, isolation, or purification of substances from a liquid. The membranes include at least one hydrophobic polymer and at least one hydrophilic polymer. 5-40 wt.-% of particles having an average particles size of between 0.1 and 15 m are entrapped. The membrane has a wall thickness of below 150 m. Methods for preparing the membranes in various geometries, and use of the membranes for the adsorption, isolation, and/or purification of substances from a liquid are explored.

Provided herein are metal organic framework/polymer mixed-matrix hollow fiber membranes and metal organic framework/carbon molecular sieve mixed-matrix hollow fiber membranes. The materials have high MOF particle loading and are easily scalable. The MOF/polymer mixed-matrix hollow fibers are formed using a dry-jet/wet-quench fiber spinning technique and show C.sub.3H.sub.6/C.sub.3H.sub.8 selectivity that is significantly enhanced over the pure polymer fiber and that is consistent with the selectivity of mixed-matrix dense films of the same MOF/polymer combination. The MOF/CMS mixed-matrix hollow fibers are formed by pyrolyzing the MOF/polymer mixed-matrix hollow fibers and show increased C.sub.3H.sub.6 permeance and increased selectivity over the MOF/polymer mixed-matrix hollow fiber membranes.

Various methods of making a reinforced membrane, devices for making the membranes, and the resulting membranes are described. The methods typically provide a reinforcing structure that includes filaments extending around the circumference of the membrane but without the filaments being part of a braided or woven structure. Some of the reinforcing structures also include longitudinal filaments. The methods and devices can be used to make a supporting structure in line with membrane formation steps, and also allow for a reinforced membrane to be produced that has a ratio of inside-to-outside diameters of 0.5 or more.

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

A porous membrane made from a poly(phenylene ether) copolymer has at least one of: a molecular weight cut off of less than 40 kilodaltons or a surface pore size of 0.001 to 0.1 micrometers. The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a porous membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous mem-brane. The porous membrane can be in the form of a sheet or a hollow fiber, and can be fabricated into separation modules.

This invention relates to aromatic block copolyimide polymers comprising both hydroxyl functional groups and carboxylic acid functional groups, their membranes and methods for making and using these polymers and membranes. The aromatic block copolyimide polymer described in the present invention comprises both hydroxyl functional groups and carboxylic acid functional groups. The gas transport properties particularly the selectivities of the aromatic block copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups were significantly improved compared to those of the aromatic random copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups.

A porous membrane made from a poly(phenylene ether) copolymer has at least one of: a molecular weight cut off of less than 40 kilodaltons or a surface pore size of 0.001 to 0.1 micrometers. The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a porous membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous membrane. The porous membrane can be in the form of a sheet or a hollow fiber, and can be fabricated into separation modules.

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

In a method of fabricating high performance CMS membranes, in which a dual-layer hollow fiber precursor fiber membrane that contains a nano-particle-filler containing core layer is extruded, a sheath layer is co-extruded with the core layer so that at least a portion of the core layer is surrounded by the sheath layer. The nano-particle filler is defect sealed. The dual-layer hollow fiber precursor fiber and the sheath layer are pyrolysed. A CMS membrane includes a core layer, a sheath layer surrounding at least a portion of the core layer and a plurality of nanoparticles disposed in the core layer.