The present invention relates to a polymer layered hollow fiber membrane based on poly(2,5-benzimidazole) (ABPBI), ABPBI copolymers and substituted polybenzimidazole (PBI) and a process for preparation thereof.

Provided are a hydrophilic porous membrane including a porous membrane and a hydroxyalkyl cellulose retained in the porous membrane, in which the average pore size differs between two surfaces of the porous membrane, the hydroxyalkyl cellulose distributed in the thickness direction of the hydrophilic porous membrane exhibits two or more peaks of detection intensity in GPC, and the weight-average molecular weight Mw.sub.min of the peak that is detected latest among the above-mentioned peaks is less than 100,000; and a method for producing a hydrophilic porous membrane, the method including separately preparing a hydrophilizing liquid including a hydroxyalkyl cellulose having a smaller weight-average molecular weight and a hydrophilizing liquid including a hydroxyalkyl cellulose having a larger weight-average molecular weight, and applying each of the hydrophilizing liquids on two surfaces of the porous membrane or sequentially on one surface thereof.

Embodiments described herein relate generally to graphene oxide membranes for fluid filtration and more specifically to graphene oxide membranes having tunable permeability, rejection rate, and flux. Some embodiments of the graphene oxide membranes disclosed herein are characterized as having a flux of at least about 2.5×10.sup.−4 gallons per square foot per day per psi with a 1 wt % lactose solution at room temperature, and a lactose rejection rate of at least 50% with a 1 wt % lactose solution.

The present invention provides a room-temperature selective swelling method of pore-forming used for preparing separation membranes, comprising: treating a dense membrane of an amphiphilic block copolymer by a composite swelling agent at 15-30° C. for 1 min-24 h, removing the residual solvent, then leaving the membrane at room temperature to dry, so as to obtain an amphiphilic block copolymer separation membrane with a bi-continuous porous structure, wherein the composite swelling agent is composed of 60-96% of a first swelling agent and 4-40% of a second swelling agent, the first swelling agent is an alcohol solvent, the second swelling agent is selected from any one or a mixture of two or more of toluene, styrene, tetrahydrofuran, 1,4-dioxane and so on. In the method of the invention, selective swelling can be achieved at room temperature, abating the energy consumption in membrane-forming process. The method has universality and can be widely used in the pore-forming process of various amphiphilic block copolymers. The swelling level and morphology can be controlled by adjusting the composition of the solvent in the swelling agent and the second swelling agent content in the swelling agent.

Disclosed are methods of manufacturing a zeolite membrane, comprising: providing at least one porous substrate; and coating the at least one porous substrate with a membrane. In some embodiments, the method further comprises hydrothermally treating the membrane with a first hydrothermal treatment step with tetrapropylammonium fluoride (TPAF) and a second hydrothermal treatment step with tetraethammonium hydroxide (TEAOH). In some embodiments, coating the substrate with a membrane comprises surrounding at least a portion of the at least one porous substrate with a precursor gel, the gel comprising a gel phase and a plurality of CHA or MFI crystals; heating the at least one porous substrate and the precursor gel; washing the at least one porous substrate; drying the at least one porous substrate; and calcining the at least one porous substrate.

Photocurable (meth)acrylate compositions for forming features on the surfaces of membranes, and particularly, on membranes used in osmosis and reverse-osmosis applications, such as membrane filters.

Photocurable (meth)acrylate compositions for forming features on the surfaces of membranes, and particularly, on membranes used in osmosis and reverse-osmosis applications, such as membrane filters.

Membranes, methods of making the membranes, and methods of using the membranes are described herein. The membranes can comprise a gas permeable support layer, an inorganic layer disposed on the support, the inorganic layer comprising a plurality of discreet nanoparticles having an average particle size of less than 1 micron, and a selective polymer layer disposed on the inorganic layer, the selective polymer layer comprising a selective polymer having a CO.sub.2:N.sub.2 selectivity of at least 10 at 57° C. In some embodiments, the membrane can be selectively permeable to an acidic gas. The membranes can be used, for example, to separate gaseous mixtures, such as flue gas.

A filter medium including: a porous first support; nanofiber webs respectively stacked at the upper and lower parts of the first support, and made of a plurality of nanofibers of which the diameters have a standard deviation of 300 nm or less; and a porous second support interposed between the first support and the nanofiber web. The filter medium is implemented by fibers having uniform diameters, and thus is easily manufactured to have a predetermined pore diameter and simultaneously has excellent uniformity of the pore diameters, thereby having excellent filtering efficiency and being more suitable when selectively separating specific objects. Backwashing is enabled at uniform pressure during backwashing such that high cleaning power is obtained. The filter medium has excellent water permeability and excellent mechanical strength so as to minimize the shape and structural deformation and damage of the filter medium.

A low cost, high selectivity asymmetric polyimide/polyethersulfone (PES) blend hollow fiber membrane, a method of making the membrane and its use for a variety of liquid, gas, and vapor separations such as deep desulfurization of gasoline and diesel fuels, ethanol/water separations, pervaporation dehydration of aqueous/organic mixtures, CO.sub.2/CH.sub.4, CO.sub.2/N.sub.2, H.sub.2/CH.sub.4, He/CH.sub.4, O.sub.2/N.sub.2, H.sub.2S/CH.sub.4, olefin/paraffin, iso/normal paraffins separations, and other light gas mixture separations. The polyimide/PES blend hollow fiber membrane is fabricated from a blend of a polyimide polymer and PES and showed surprisingly unique gas separation property with higher selectivities than either the polyimide hollow fiber membrane without PES polymer or the PES hollow fiber membrane without PES polymer for gas separations such as for H.sub.2/CH.sub.4, He/CH.sub.4, H.sub.2S/CH.sub.4, CO.sub.2/CH.sub.4 separations.