A novel fibrous membrane comprises at least one substrate layer comprising at least 80% by weight of microfibers that carry positively charged and/or negatively charged functional groups, and at least one layer of filtration material attached to the substrate layer, wherein the layer of filtration material comprises at least 80% by weight of nanofibers that carry negatively charged and/or positively charged functional groups. The fibrous membrane is able to remove or reduce the concentration of bacteria, viruses and heavy metals while maintaining relatively high water flow. A filter comprising the fibrous membrane and a method for manufacturing the fibrous membrane are also provided.

A spunbonded nonwoven fabric includes thermoplastic fibers, wherein the thermoplastic fibers are conjugate fibers in which a low-melting polymer having a melting point lower by 10 to 140 C. than that of a high-melting polymer is provided around the high-melting polymer, the spunbonded nonwoven fabric has a non-pressure bonding portion having an apparent density of 0.20 to 0.60 g/cm.sup.3, when a long axis length of a fiber cross section of the non-pressure bonding portion is a and a short axis length thereof is b, a fiber flatness a/b is 1.5 to 5, and an air permeability satisfies formula (1):

[air permeability (cc/cm.sup.2.Math.sec)]520exp(0.0236[basis weight (g/m.sup.2)]2.85[apparent density (g/cm.sup.3)])(1).

The present disclosure relates to hollow fiber tangential flow filters, including hollow fiber tangential flow depth filters, for various applications, including bioprocessing and pharmaceutical applications, systems employing such filters, and methods of filtration using the same.

Composites comprising polymeric nanofibers, metal oxide nanoparticles, and optional surface-segregating surfactants and precursor compositions are disclosed. Also disclosed are nonwoven mats formed from the composites and methods of making and using the composites. The composites enable the deployment of nanostructured materials for water treatment within a self-contained membrane with high water fluxes, as well as a number uses.

Membranes suitable for use in membrane distillation are provided. Such membranes may include nano-fibrous layers with adjustable pore sizes. The membranes may include a hydrophobic nanofibrous scaffold and a thin hydrophilic protecting layer that can significantly reduce fouling and scaling problems.

A periodic mesoporous organosilica (PMO) nanoparticle functionalized nanocomposite membrane (NCM) for membrane distillation, the NCM including: polymer fibers such as polyetherimide fibers aggregated into a matrix; and hydrophobic PMO nanoparticles disposed on the polymer fibers. The PMO nanoparticles include a framework connected by organic groups and pentafluorophenyl groups. Good membrane flux and anti-fouling was demonstrated. Membranes can be prepared by electrospinning.

The present invention relates to the technical field of filtering materials and provides a reverse osmosis membrane support material. The support material is obtained by hot pressing treatment of a surface layer, a middle layer and a bottom layer which are sequentially disposed from top to bottom. The surface layer and the bottom layer are each a spunbond non-woven fabric layer made of thermoplastic polymer spunbonded fibers, and the middle layer is a polymer nanofiber membrane. In accordance with the invention, the comprehensive mechanical strength of the reverse osmosis membrane support material is improved, and the overall anti-leakage performance is enhanced. A spunbond technology and a nanofiber preparation technology are combined organically, and the method is simple and controllable. The support material can be produced in batches.

A nanofiber for a filter medium is provided that includes fiber-forming ingredients including polyacrylonitrile (PAN) and polyvinylidene fluoride (PVDF) and an emulsifying agent for improving the miscibility of the fiber-forming ingredients. The nanofiber has excellent mechanical strength and chemical resistance and, at the same time, significantly increased hydrophilicity without a separate surface modification/treatment to/on the nanofiber. A filter medium comprising said nanofiber can exhibit improved flux and filtration efficiency and excellent physical properties in a water treatment process in which a pressure equal to or more than a predetermined level is applied and which requires the filter medium to have high mechanical strength and in a water treatment process which requires chemical resistance as the liquid being filtered is strongly acidic or alkaline. Further, since the nanofiber has significantly superior spinnability, the mass productivity of the filter medium is significantly improved, and the unit costs of production can be reduced.

The present disclosure relates to hollow fiber tangential flow filters, including hollow fiber tangential flow depth filters, for various applications, including bioprocessing and pharmaceutical applications, systems employing such filters, and methods of filtration using the same.

A water filtration membrane is provided, capable of removing heavy metal ions, filtering out particulates, filtering out bacteria, as well as removing herbicides and volatile organic compounds (VOCs) from water. The membrane is composed of a mat of randomly oriented nanoparticle-coated nanofibers. The nanofibers are covalently bonded to a plurality of substantially uniformly-distributed ceramic nanoparticles embedded in or adhered on the surface of the polymer nanofibers through reactive functional groups. The ceramic nanoparticles have a pattern of deep grooves formed on the nanoparticle surfaces. The bonding of the nanoparticles to the nanofibers is sufficient to retain the nanoparticles on the nanofiber surfaces when water flows through the water filtration membrane. The diameter of the nanofibers is 50-200 nm. The size of the nanoparticles is <40 nm, with a zeta potential of 40 to 45 mV in a dispersion medium. The nanoparticle deep grooves have an average size of approximately 1.2 nm or less.