The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a precursor polymer is pyrolyzed to form a carbon molecular sieve membrane that is then exposed to a conditioning atmosphere comprised of a target permeate gas molecule such as ethylene when the membrane is desired to separate it from a light hydrocarbon gas stream. The exposure to the ethylene desirably occurs prior to the CMS permeance and selectivity combination substantially changing (e.g., within 5 days) of cooling from the pyrolyzing temperature. The CMS membranes have shown an improved combination of selectivity and permeance as well as stability and are useful to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.

The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a polyimide precursor polymer is pyrolyzed to form a carbon molecular sieve membrane by heating, in a furnace, said polyimide precursor polymer to a final pyrolysis temperature of 600 C to 700 C at a pyrolysis heating rate of 3 to 7 C/minute from 400 C to the final pyrolysis temperature, the final pyrolysis temperature being held for a pyrolysis time of at most 60 minutes in a non-oxidizing atmosphere. In a particular embodiment, the cooling rate from the pyrolysis temperature is accelerated by methods to remove heat. The CMS membranes have shown an improved combination of selectivity and permeance as well as being particularly suitable to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.

Systems, devices and methods for molecular separation including a molecular separation device comprising at least a polycrystalline metal-organic framework (MOF) and a nanocrystalline, zeolite MFI, wherein the MOF forms a polycrystalline membrane with zeolite MFI nanoparticles dispersed therein, and the MOF membrane matrix contacting and surrounding the zeolite MFI nanoparticles form a permselective nanoporous structure.

Magnesium ion selective electrode membranes and the preparation thereof. The membranes are rendered highly selective for magnesium ions by the addition of acidic groups to the preferably PVC membrane, either by introducing a lipophilic compound comprising an acidic group covalently linked to a C4-C18 alkyl-substituted phenyl group (e.g. bis-4-octylphenyl phosphoric acid) into the membrane comprising the magnesium selective ionophore (e.g. a neutral ionophore 1,10-phenanthroline derivative) or by covalently linking an acidic (e.g. a carboxylic) group to the ionophore (e.g. a 1,10- phenanthroline derivative).

A filter medium is provided. According to one embodiment of the present invention, the filter medium is implemented by including: a porous second support and a nanofiber web which are sequentially stacked on each of an upper portion and a lower portion of a first support; and a channel through which a filtrate filtered in the nanofiber web flows in a direction of the first support, wherein the first support, the second support, and the nanofiber web satisfy predetermined conditions on a basis weight and a thickness of each layer. In a water treatment operation of the filter medium, the shape, structural deformation, and damage of the filter medium can be minimized, excellent filtration efficiency can be implemented, and a channel can be smoothly secured, thereby securing high flux. In addition, even at high pressure applied during backwashing, the filter medium has an extended use period due to excellent durability of the filter medium. Accordingly, the filter medium can be variously applied in various water treatment fields.

A method of encapsulating an engineered pellet in a porous membrane is disclosed. The method includes the steps of: (i) dissolving a membrane solute in a membrane solvent to produce a membrane solution; (ii) applying the membrane solution to a pellet to form a pellet encapsulated with the membrane solution; (iii) subjecting the membrane solution that encapsulates the pellet to a phase inversion and; (iv) drying the pellet to form a porous membrane encapsulated pellet. A porous membrane encapsulated pellet is also described.

Provided is a method of forming a filter module. The method includes: forming a non-pore ion-exchange membrane including: preparing a mixed solution of a polymer material and an ion-exchange material; and electrospraying the mixed solution to obtain the non-pore ion-exchange membrane; and interposing the non-pore ion-exchange membrane between a first polymer nanofiber web and a second polymer nanofiber web to form the filter module.

Disclosed is a 1D nanofibers quasi-aligned, grid structure cross-laminated, and pore distribution and size controlled 3D polymer nanofiber membrane, and manufacturing method thereof. A 3D polymer nanofiber membrane controlled in pore size and porosity is formed by employing an electrospinning pattern forming apparatus that includes double insulating blocks quasi-aligns nanofibers in a specific direction by transforming an electric field and includes a current collector rotatable in 90. Additionally, the 3D polymer nanofiber membrane may be used for air filters, separator, water filters, cell culture membranes, and so on by allowing various properties thereto through a functional surface coating.

A hollow fiber membrane contains a vinylidene fluoride-based resin and polyethylene glycol. In the hollow fiber membrane, the polyethylene glycol has a content of 1.0 part by weight or more and less than 5.0 parts by weight with respect to 100 parts by weight of the vinylidene fluoride-based resin. In a case where the hollow fiber membrane is divided in three equal parts by a line drawn from an inner surface side to an outer surface side of the hollow fiber membrane in a radial direction of a cross section perpendicular to a longitudinal direction of the hollow fiber membrane, and where polyethylene glycol normalized intensities at respective intermediate points are defined as inner surface part a, central part b, and outer surface part c, c is less than 0.3 and a is 0.5 or more.

Polymer compositions containing polyethylene particles having a multi-modal molecular weight distribution are disclosed. The polymer compositions are well suited to producing porous substrates through a sintering process. Formulations made according to the present disclosure can produce porous substrates having improved flexibility demonstrated by an increased flexural strength while still retaining excellent pressure drop characteristics.