B01D2323/2185

METHOD FOR PRODUCING A POLYPHENYLSULFONE POROUS HOLLOW FIBER MEMBRANE
20190374909 · 2019-12-12 ·

In the production of a polyphenylsulfone porous hollow fiber membrane by a wet spinning method or a dry-wet spinning method using a spinning dope comprising a water-soluble organic solvent solution of polyphenylsulfone, hydrophilic polyvinylpyrrolidone, and ethylene glycol, wherein N,N-dimethylformamide with a concentration of 70 to 100 wt. %, preferably 85 to 100 wt. %, more preferably 100 wt. %, is used as a core liquid. The resulting porous hollow fiber membrane enables stable production without imposing burdens on the environment and provides a water purification membrane having high water permeability and excellent filtration performance.

Fe-Al-based metal porous membrane and preparation method thereof

The present invention discloses a FeAl-based metal porous membrane and a preparation method thereof, which relate to the technical field of industrial gas-solid and liquid-solid separation and purification, and mainly address problems in the prior art, such as cracking-prone and peeling of a membrane layer of an existing FeAl-based metal porous membrane during its preparation and use. The preparation method of the present invention comprises the steps of: adding a FeAl-based metal powder and a metal fiber powder into an organic-additive-added water-based solvent, and mixing them into a slurry; casting the slurry, through a casting machine, to form a membrane green body on a metal substrate layer, and letting it dry; and placing the dried membrane green body in a sintering furnace, to remove organic substances and perform high-temperature sintering and predetermined-temperature reaction synthesis.

Photothermal photocatalytic membrane for seawater desalination and uranium extraction and preparation method therefor

The present disclosure relates to the field of materials for uranium extraction from seawater (UES), and in particular, to a photothermal photocatalytic membrane for seawater desalination and uranium extraction and a preparation method therefor. The present disclosure provides a photothermal photocatalytic membrane for seawater desalination and uranium extraction and a preparation method therefor. The preparation method includes: fixing a treated carbon cloth to a glass plate, pouring a casting solution 1 onto the carbon cloth to form a first layer of film, forming a second layer of film using a casting solution 2, and putting the second layer of film into a first coagulation bath and a second coagulation bath in sequence to form the photothermal photocatalytic membrane. The photothermal photocatalytic membrane is supported by the carbon cloth, and a surface of the photothermal photocatalytic membrane is of a micro-nano structure.

POROUS MEMBRANE AND PROCESS FOR PRODUCING POROUS MEMBRANE

A porous membrane has a thickness of 150 m or greater. The pore diameters of a first surface are smaller than the pore diameters of a second surface. The average value of the pore diameters of the first surface is 60 nm or less, and the coefficient of variation of the pore diameters is 10% or greater and 50% or less.

High toughness hollow fiber membranes based on vinylidene fluoride polymers

Hollow fiber membranes having improved toughness and durability are prepared using a vinylidene fluoride polymer-containing component, such as Kynaro resins, having relatively low crystallinity. One aspect of the invention provides a membrane in the form of a fiber, wherein i) the fiber has a porous wall of a polymeric component enclosing a central hollow space extending the length of the fiber, ii) the polymeric component has a crystallinity as determined by wide angle x-ray diffraction of less than about 35%, iii) the polymeric component is comprised of at least one homopolymer or copolymer of vinylidene fluoride and iv) the membrane has an energy to break of at least about 0.5 J per square mm of membrane cross section.

METHOD, SPINNERET AND SYSTEM FOR FABRICATING MULTILAYER MEMBRANES
20190099724 · 2019-04-04 · ·

The present invention is related to a method for fabricating multilayer singlebore membranes (10) or multilayer multibore membranes (20) for ultrafiltration applications including the following method steps: (a) feeding at least a material of a substrate (12), at least one material of a functional layer (14, 15) and a bore fluid (36) to a spinneret (30) simultaneously; (b) forming said membranes (10, 20) as a tube-like string (54) in a one-step process in said spinneret (30); (c) thereby assigning a functionality to said functional layer (14, 15) applied on at least one surface (13, 17) of said substrate (12). The invention is also related to a spinneret (30) for fabricating multilayer singlebore membranes (10) or multilayer multibore membranes (20), using the inventive method, and to a system comprising such a spinneret (30).

COMPOSITION AND METHOD FOR MANUFACTURING SULFONE POLYMER MEMBRANE

The invention pertains to a polyaryl ether sulfone polymer solution [solution (SP)] comprising: at least one sulfone polymer [polymer (PSI)] having recurring units, wherein more than 50% moles, with respect to all the recurring units of polymer (PSI), are recurring units (R.sub.PSI) selected from the group consisting of those of formulae (R.sub.PSI-1) and (R.sub.PSI-2) herein below: (R.sub.PSI-1) (R.sub.PSI-2) wherein: each of E, equal to or different from each other and at each occurrence, is selected from the group consisting of those of formulae (E-1) to (E-3): (E-I) (E-II) (E-III) each R is independently selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium; and j is zero or an integer of 1 to 4; is a bond or a divalent group optionally comprising one or more than one heteroatom; preferably T is selected from the group consisting of a bond, CH.sub.2, C(O), C(CH.sub.3).sub.2, C(CF.sub.3).sub.2, C(?CCI.sub.2), C(CH.sub.3)(CH.sub.2CH.sub.2COOH), and a group of formula: (A) at least one polar organic solvent [solvent (S)]; and at least one mixture of polyhydroxyl aliphatic alcohols having from 1 to 6 carbon atoms or derivatives thereof [mixture (PHA)], said mixture (PHA) comprising at least one ethylene glycol compound [compound (EthyGly)] and at least one glycerol compound [compound (Gly)], to its use for manufacturing membranes, and to membranes obtained therefrom.

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Surface-modified separation membrane and method for modifying surface of separation membrane
10207228 · 2019-02-19 · ·

A surface-modified separation membrane of the present invention comprises a separation membrane, and a coating layer formed on the surface of the separation membrane for improving the contamination resistance and chemical resistance of the separation membrane, wherein the coating layer is implemented with a nanoscale thickness of the coating layer in order to inhibit a decrease in permeation flux of the separation membrane before and after coating the coating layer, and comprises: dopamine for providing, to the coating layer, an adsorption force to be bound stably with the separation membrane; and a hydrophilic material which is bound to the dopamine through secondary bonding or cross-linking containing a hydrogen bond in order to inhibit the deterioration of the durability of the coating layer, and provides hydrophilicity to the surface of the separation membrane in order to protect the separation membrane from hydrophobic contaminants. A method for modifying the surface of a separation membrane of the present invention comprises the steps of: injecting a separation membrane to be surface-modified into a reactor; adding a mixture solution, which is formed by adding a hydrophilic material to a Tris-buffer solution having an adjusted pH range at which dopamine reacts and stirring the same, to the reactor; adding dopamine and an initiator, which induces the cross-linking of the hydrophilic material and dopamine, to the reactor at a predetermined temperature range; and forming a coating layer comprising dopamine and the hydrophilic material on the separation membrane through thermal cross-linking at the predetermined temperature range while injecting oxygen into the reactor.

SEPARATION MEMBRANE

The problem addressed by the present invention is to provide a separation membrane with superior permeation performance and separation performance and having few occurrences of defects. The present invention relates to a separation membrane wherein: the separation membrane has a layer (I) with a thickness of 0.5-100 ?m; letting, in a cross-section in the direction of thickness of the layer (I), region a be a region with a depth of 50-150 nm from a surface (surface A), region b a region with a depth of 50-150 nm from the other surface (surface B), and region c a region with a thickness of 100 nm where the depth from both surfaces is the same, the average pore diameter Pa for region a and the average pore diameter Pb for region b are both 0.3-3.0 nm and the average pore diameter Pc for region c is 3.0 nm or less; and the percentage of open area Ha for region a, the percentage of open area Hb for region b, and the percentage of open area Hc for region c satisfy the following equations. 2Hc<Ha 2Hc<Hb

PREPARATION, REGENERATION AND APPLICATION OF A CHELATING MICROFILTRATION MEMBRANE

A polyvinylidene fluoride (PVDF) casting membrane solution is shaped as a flat sheet membrane by thermally induced phase separation (TIPS), the PVDF membrane is defluorinated with an alkaline potassium permanganate solution, and then the carbon chain is extended with glycidyl methacrylate (GMA) as the graft monomer, and finally the nucleophilic substitution is carried out between melamine and GMA to produce a chelating microfiltration membrane for capturing and enriching heavy metals with high flux and high capacity.