The present disclosure relates to the field of porous material synthesis, and particularly to a method for preparing porous aromatic framework membranes based on an inorganic salt template method. It aims at the problem of difficulty of preparation of porous aromatic framework membranes in large scale and large size. It uses alkynyl-containing building units and bromine-containing building units as raw materials and obtains continuous, dense, defect-free porous aromatic framework membranes through Sonogashira-Hagihara coupling polymerization. It specifically successfully prepares porous aromatic framework nanosheets on an inorganic salt substrate, and then produces a centimeter-scale large size continuous porous aromatic framework membrane through self-assembly. The method has mild conditions, a simple preparation process, and it is easy to operate. The prepared membranes have high yield and large area, and meet the requirements of actual industrial production.

The present disclosure discloses a method for preparing a metal-organic framework filter comprising the steps of bringing metal sources into contact with organic ligands and forming a metal-organic framework filter on substrates by a hot-pressing method. By the method of the present disclosure, a large amount of metal-organic framework filters with high purity can be obtained quickly and easily, thereby realizing industrialized production and application and the method has such advantages as low cost, simple operation, rapid production, batch product and high purity.

A polyvinylidene difluoride membrane is provided. The polyvinylidene difluoride membrane including polyvinylidene difluoride having a melt viscosity of 35 to 60 (k poise), and the surface of the polyvinylidene difluoride membrane has a pore size of 0.1 ?m to 5 ?m. A method of manufacturing a porous polyvinylidene difluoride membrane and a method of purifying brine are also provided. The method of purifying brine includes the above-mentioned polyvinylidene difluoride membrane.

The present disclosure relates to improved semipermeable membranes based on acrylonitrile copolymers for use in dialyzers for the extracorporeal treatment of blood in conjunction with hemodialysis, hemofiltration or hemodiafiltration. The present disclosure further relates to methods of producing such membranes.

Disclosed is a hollow-fiber membrane blood purification device having an improved antioxidant performance, good water permeation performance and blood compatibility performance, and economic rationality. The present invention provides a hollow-fiber membrane blood purification device including hollow-fiber membranes filled in a vessel, in which the hollow-fiber membranes contain a hydrophobic polymer, a hydrophilic polymer and a fat-soluble vitamin, when a hollow-fiber membrane bundle is divided into five sections in a lengthwise direction and divided sections positioned in endmost portions are defined as body end portions, an amount of the fat-soluble vitamin present in at least one of the body end portions is the largest among amounts of the fat-soluble vitamin present respectively in all the divided sections, and an amount of the fat-soluble vitamin per m.sup.2 of a hollow-fiber membrane inner surface of the at least one body end portion is 20 mg/m.sup.2 or more and 300 mg/m.sup.2 or less.

Disclosed herein is a method of making a crosslinked membrane such as a crosslinked hollow fiber membrane. The method comprises (a) preparing a polyimide polymer comprising carboxylic acid functional groups from a reaction solution comprising monomers and at least one solvent; (b) treating the polyimide polymer with a diol at esterification conditions to form a monoesterified polyimide polymer; (c) forming a monoesterified polyimide membrane or dense film from the monoesterified polyimide polymer; and (d) subjecting the monoesterified polyimide membrane or dense film to transesterification conditions under a CO.sub.2 atmosphere to form a crosslinked polyimide membrane or dense film.

The present disclosure relates to a porous membrane and a method of manufacturing the same, and more particularly, to a thermally stable porous membrane capable of securing thermal stability and long-term stability of gas separation performance at high temperatures, and a manufacturing method thereof. This invention is related to a porous membrane comprising: a first Zeolitic Imidazolate Fragments (ZIFs) part formed on a surface of a porous support; and a second ZIFs part embedded in the porous support, wherein the second ZIFs part is formed in a state in which it penetrates from an interface between the first ZIFs part and the second ZIFs part to a predetermined depth.

The present invention deals with a method for obtaining membranes in the form of hollow fibers with application in the field of carbon dioxide removal from natural gas. The aforementioned membranes are obtained by means of heat treatment of polymeric membranes. In this method, polymeric membranes are obtained by a phase-inversion technique by immersion-precipitation and are subsequently subjected to a heat treatment, that is, that the membranes effectively become precursor membranes of the heat treatment. The heat treatment process involves the optimization of the heating rate, temperature, and stabilization time variables, aiming at the improvement of the transport properties of the polymeric membranes. After the heat treatment, it becomes possible to use the membranes in separation processes of gases which operate at pressures greater than 30 bar, with selectivity for carbon dioxide (CO.sub.2).

A method of manufacture of crosslinked, edible, porous hollow fibers and sheet membranes suitable for the manufacture of clean meat products, the hollow fibers and sheet membranes made therefrom and methods of use thereof.

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%.