Organic solvent nanofiltration membranes that include at least one polymer coated expanded polyparaxylylene (eP-PX) membrane are provided. A substrate/support layer may be positioned on one side of the ePPX membrane. In some embodiments, the substrate/support layer is sandwiched between ePPX membranes. Processes for manufacturing and using such organic solvent nanofiltration membranes are also provided. The organic solvent nanofiltration membranes are capable of separating and/or concentrating solutes from a solution comprising a lower molecular weight organic solvent with high permeability. The polymer coated ePPX membranes may also be resistant to chemical attack, resistant to gamma radiation, thermally stable, biocompatible, and strong.

Water or wastewater filtration processes and systems have a plurality of membrane modules, each having filter media therein, the plurality of membrane modules arranged in parallel fluid flow, a main bottom feed conduit, a main top feed conduit, and separate feed conduits fluidly connecting the main bottom feed conduits and the main top feed conduits to respective membrane modules. A main filtrate conduit, and separate filtrate conduits fluidly connect respective membrane modules to the main filtrate conduit. A backwash conduit fluidly connects the main filtrate conduit to respective membrane modules through the main top and bottom feed conduits. A pump having a pump feed conduit and a pump discharge conduit, the pump discharge conduit fluidly connected to the main top and bottom feed conduits, and a plurality of automatically controllable valves positioned in the main top and bottom feed conduits, the main filtrate conduit, the pump discharge conduit, and the backwash conduit, with a controller configured to actuate the plurality of automatically controllable valves to control feed and backwash flows through the membrane modules using pressure developed only by the pump. The pump is preferably operated by a variable-speed prime mover.

There is provided a semi-permeable membrane comprising: at least two two-dimensional (2D) heterostructure layers of; and a polyelectrolyte layer between each 2D heterostructure layer of the at least two 2D heterostructure layers. There is also provided a method of preparing the membrane comprising: mixing a 2D heterostructure solution and a polyelectrolyte solution to form a mixture; and vacuum filtering the mixture onto a substrate to form the membrane.

The present disclosure relates to a ceramic graphene oxide nanofiltration membrane which is high in mechanical stability while having ion removal ability by alternately stacking GO and PEI on a ceramic nanomembrane by allowing a carboxyl group (—COOH) and an amine group (—NH.sub.2) to form a covalent bond in the presence of N-ethyl-N′-[3-(dimethylamino)propyl]carbodiimide hydrochloride (EDC), thereby forming an amide group (—CONH), and a method for manufacturing the same.

A process for preparing a hollow fiber includes the steps of providing a dope solution including polyamide imide (PAI), providing an aqueous bore solution including polyethylene imine (PEI), extruding the dope solution in an cross-sectional annular shape and ejecting the bore solution in the center of the annular shape, allowing the PAI and the PEI to react, thereby forming an internal surface layer including the cross-linked reaction product, and forming a polyamide Thin Film Composite (TFC) layer by interfacial reaction of aqueous di- or triamine compound and organic di- or triacylhalide compound on the internal surface layer including the cross-linked reaction product.

One aspect of the present disclosure provides a production method for a porous membrane including pores, and concave portions having an average opening diameter greater than an average pore diameter of the pores on at least one of a pair of main surfaces, the method including a step of forming the concave portion on a surface to be the main surface.

An acidic gas separation membrane is selectively permeable to an acidic gas, and includes a first porous layer and a resin composition layer formed on the first porous layer with use of a resin composition. The resin composition contains a modified polyamine obtained by introducing at least one of an acidic dissociable group and a salt thereof into a polyamine. The acidic dissociable group is at least one selected from the group consisting of a carboxy group, a sulfonic acid group, an oxysulfonic acid group, a phosphoric acid group, and an oxyphosphoric acid group. The polyamine is at least one selected from the group consisting of polyethyleneimine, polyallylamine, and polyvinylamine.

A bipolar membrane comprising a cation exchange mat of one or more cation exchange polymers, an anion exchange mat of one or more anion exchange polymers, and an internal 3D bipolar interface, disposed between the cation and anion exchange layers, including a mixture of at least one cation exchange polymer and at least one anion exchange polymer, such that an interface of the at least one cation exchange polymer and the at least one anion exchange polymer is the internal 3D bipolar interface that has a large area, and the at least one cation exchange polymer in the 3D bipolar interface is connected to the one or more cation exchange polymers of the cation exchange layer, and the at least one anion exchange polymer in the 3D bipolar interface is connected to the one or more anion exchange polymers of the anion exchange layer.

The present invention relates to a method for the production of a positively charged membrane. Furthermore the present invention relates to a positively charged membrane obtainable by the methods of present invention and the use of these positively charged membranes.

The present invention is directed to rigid filtration apparatus comprising a filter support and filter membrane. Such filter support is comprised of a central core. Radiating from the central core are a plurality of pleats composed of two angled walls terminating at a contact point. Such longitudinal walls circumscribe a longitudinal channel situated between the walls wherein the longitudinal channel is in communication with the central core. The longitudinal walls are comprised of a plurality of openings along the walls. A filter membrane having biocidal components may be utilized with the filter support to effectively treat contaminated fluid, gas or air. Alternatively, the composition of the rigid central core and the rigid pleats may be composed of different materials to selectively remove chemicals, biological components or pharmaceuticals in a multi-stage treatment process.