Stable maintenance of high separation performance of a separation membrane having a separation layer comprising a compact carbon layer is described in addition to a separation membrane having a separation layer comprising a compact carbon layer, wherein particles are attached to the compact carbon layer, recesses are present in the compact carbon layer, and the particles are at least partially stuck in the recesses.

Provided are a recyclable electret filtering membrane, a preparation method therefor and a cleaning and charge regeneration method therefor. The preparation method includes: dissolving fluorine-containing polymer particles and polyoxyethylene particles in deionized water to prepare a spinning solution, and then performing electrostatic spinning, calcining, cooling, drying and corona charging to obtain the recyclable electret filtering membrane. A surface of the filtering membrane is subjected to water drop rolling cleaning and friction electrification after dust holding, and then dried to realize charge regeneration and reuse. The filtering membrane obtained in the present invention has an initial surface potential of (?600)-(?950) V, the potential can be regenerated to (?700)-(?1000) V by water drop rolling and electrification after dust holding, the charge recovery rate is 90%-125%, the dust removal rate is 90%-100%, and the filtering efficiency for PM.sub.2.5 is equal to or greater than 94%.

The present disclosure relates to capillary dialyzers for blood purification comprising from 85-95% crimped fibers and from 5-15% non-crimped fibers.

The invention relates to a virus filter membrane which can be used for the removal of virus particles including parvovirus. The invention further relates to a method for producing the membrane. The membrane comprises polyacrylonitrile and polyvinylpyrrolidone.

Provided is a simple method for producing a cell concentrate (other than human blood) in a short time with neither loss of cells nor an excessive burden on cells. Included is a method for producing a cell concentrate using an inside-out filtration system for processing a cell suspension, the system including: a cell suspension inlet port; a filtrate outlet port; a cell suspension outlet port; and hollow fiber separation membranes provided between the cell suspension inlet port and the cell suspension outlet port, wherein the membranes have a total cross-sectional area of 0.5-1.5 cm.sup.2, the membranes have an inside membrane area of 0.2 m.sup.2 or less, the suspension is flowed inside the membranes at a linear velocity of 500-1200 cm/min, and the quotient of the division of the initial filtrate flow rate from the filtrate outlet port by the flow rate into the cell suspension inlet port is 0.4-0.7.

Embodiments of the present disclosure provide for composite materials, methods of making composite materials, methods of using composite materials, and the like. In particular, the present application relates to hollow fibers and to pressure-retarded osmosis systems comprising said fibers. The hollow fibers have an inside layer and an outside layer, wherein the outside layer covers an outside surface of the inside layer, wherein the inside layer forms a boundary around the lumen, wherein the inside layer includes a bi-layer structure, wherein the bi-layer structure includes a sponge-like layer and a finger-like layer, wherein the sponge-like layer is disposed closer to the lumen of the hollow fiber and the finger-like layer is disposed on the sponge-like layer on the side opposite the lumen, wherein the outside layer includes a polyamide layer.

The present invention relates to units for separation of gas mixtures using hollow fiber membranes and may be used in chemical, oil, gas and other industries. More specifically, this invention relates to the structure of the membrane gas separation module which may be applied, for instance, in membrane separation units for helium concentrate. The membrane gas separation module comprises the horizontal body with end covers and membrane cartridges made of a bundle of hollow fibers and located in an inversed manner in relation to the center. The body comprises symmetrical end sections of large diameter which are mated by conical transition sections with the central section of minor diameter. In this case length of end sections corresponds with length restricted by the body end and input area of membrane cartridges, and central section inner diameter is configured to provide both free mounting/dismounting of membrane cartridges and tight fit thereof at the sealing point with ring gaskets. Feed gas input nozzles are located on end sections of the body perpendicularly to its longitudinal axis in front of input areas of membrane cartridges, permeate output nozzles are located on end sections of the body near end covers perpendicularly to the body longitudinal axis. The technical result is reduction of weight and dimensional properties of the membrane module and the whole gas separation unit in general, as well as reduction of labor intensity of operations during mounting/dismounting of body end covers of the membrane module.

The present invention is directed to a process for the preparation of a tube with an outer diameter in the range of from 10 m to 250 m consisting of a composition comprising a thermoplastic polyurethane as well as to a tube with an outer diameter in the range of from 10 m to 250 m consisting of a composition comprising a thermoplastic polyurethane obtained or obtainable by the process according to the invention. The invention is further directed to the use of a tube according to the invention as a tube for the transportation of a fluid or as gas membrane tube or as an elastic fiber.

Systems and methods for the recovery of rare earth elements are provided. The systems and methods generally include membrane assisted solvent extraction using permeable hollow fibers having an immobilized organic phase within the pores of the hollow fibers. The permeable hollow fibers are generally in contact with an acidic aqueous feed on one side thereof and a strip solution on another side thereof. The systems and methods generally include the simultaneous extraction and stripping of rare earth elements as a continuous recovery process that is well suited for post-consumer products, end-of-life products, and other recovery sources of rare earth elements.

Problems that the invention is to solve is to provide a composite hollow fiber membrane being excellent in separation performance and permeation performance, having high membrane strength, and capable of being easily produced, and a method for producing the same. The present invention relates to a composite hollow fiber membrane including at least a layer (A) and a layer (B), in which the composite hollow fiber membrane has an outer diameter of 20 to 350 ?m and an inner diameter of 14 to 250 ?m, the tensile modulus of the composite hollow fiber membrane is from 1,000 to 6,500 MPa, the layer (A) contains a cellulose ester, the thickness of the layer (A) is from 0.01 to 5 ?m, and the open pore ratio H.sub.A of the layer (A) and the open pore ratio H.sub.B of the layer (B) satisfy H.sub.A<H.sub.B.