40results about How to "High water flux" patented technology

The invention discloses a preparation method of a reverse osmosis composite membrane containing nano zeolite molecular sieves. The method comprises the following steps: dispersing the nano zeolite molecular sieves into polyamine aqueous solution to obtain a mixture A; dipping a polysulfone supporting membrane into the mixture A, taking out the membrane and then removing a solvent for the memebrane, carrying out interfacial polymerization on the membrane without the solvent in poly-acyl chloride solution, and after-treating the membrane after interfacial polymerization finishes to obtain the reverse osmosis composite membrane containing the nano zeolite molecular sieves; or dispersing the nano zeolite molecular sieves into the poly-acyl chloride solution to obtain a mixture B; and dipping the polysulfone supporting membrane into the polyamine aqueous solution, taking out the membrane and then removing the solvent for the membrane, carrying out interfacial polymerization on the membrane without the solvent in the mixture B, and after-treating the membrane after interfacial polymerization finishes to obtain the reverse osmosis composite membrane containing the nano zeolite molecular sieves. The reverse osmosis composite membrane containing the nano zeolite molecular sieves obtained by the preparation method of the invention has higher desalination rate, higher water flux and higher mechanical strength.

A method for preparing a double layered porous hollow fiber membrane and the device and product thereof. The method comprises preparing uncured porous hollow fiber with larger pore diameters as the inner robust supporter of the membrane from thermoplastic polymeric resins by thermal induced phase separation (TIPS) method and then binding an ultra thin coating layer with hydrophilic microfiltration or ultrafiltration function and fine pore diameters prepared on the outer surface of the robust hollow fibers from a solution of the thermoplastic polymeric resins by a coating process using non-solvent induced phase separation (NIPS) method. The double layered porous hollow fiber membranes have such excellent mechanical strength and high water permeation as the membranes prepared by thermal induced phase separation (TIPS) method, such high accurate filtration effect, high hydrophilic effect and high fouling resistance as the membranes prepared by non-solvent induced phase separation (NIPS) method, and high binding force of the membranes between the layers by the above method.

A method for preparing a composite multilayer porous hollow fiber membrane and the device and product thereof. The method comprises preparing uncured porous hollow fibers with larger pore diameters as the inner supporter of the membrane from thermoplastic macromolecule polymer resins by thermal induced phase separation method and then bonding a superthin coating layer with microfiltration or nanofiltration function and small pore diameter prepared on the outer surface of the hollow fibers from a solution of the thermoplastic macromolecule polymer resins by a coating process using non-solvent induced phase separation method. The composite multilayer porous hollow fiber membrane has such excellent mechanical strength and high water flux as the membranes prepared by thermal induced phase separation method, such high precision filter effect and high contamination resistance as the membranes prepared by non-solvent induced phase separation method, and high binding force of the membrane prepared by the above method.

The invention relates to a method for preparing a polyvinylidene fluoride composite cellulose acetate forward osmosis membrane. The conventional product has a serious inside concentration polarization phenomenon and low actual flux. The method comprises the following steps of: preparing a polyvinylidene fluoride cast membrane solution from polyvinylidene fluoride and additive; preparing a cellulose acetate cast membrane solution from cellulose acetate, cellulose triacetate and molecular sieve; and uniformly coating the polyvinylidene fluoride cast membrane solution on a non-woven fabric to obtain a hydrophilic polyvinylidene fluoride micro-filtration base membrane, drying or naturally drying in air to form a dry hydrophilic polyvinylidene fluoride membrane, uniformly coating the cellulose acetate cast membrane solution on the dry hydrophilic polyvinylidene fluoride membrane, and thus obtaining the composite forward osmosis membrane. The forward osmosis membrane prepared by the method has high mechanical strength and solvent tolerance, high water flux and high salt intercepting rate, and can be applied in the fields of desalting of seawater and brine, softening of hard water, first-aid water bags and the like.

The present invention relates to systems, methods and uses for recycling at least a part of water lost during various renal replacement therapy processes, e.g. in the preparation of a fresh dialysate solution or fresh reconstitution fluid for kidney disease dialysis and hemofiltration by utilizing water from the spent fluids. The system of the invention is useful in hemodialysis and in peritoneal dialysis as well as in hemofiltration for reuse of water from filtrates and spent fluids. In addition, the system of the invention is useful in the development of a renal assist device or artificial kidney.

The invention provides a preparation method of a composite forward osmosis membrane. A nanotube and cellulose triacetate are combined, the nanotube has a good water channel, the transferring speed of water molecules in the forward osmosis membrane is increased, the water flux in a forward osmosis process is greatly improved, the saline ion interception capability is improved, and the salt intercepting rate of the forward osmosis membrane is improved due to the special cavity structure of the nanotube. The invention also provides the composite forward osmosis membrane prepared by the method. The composite forward osmosis membrane has high water flux and high salt intercepting rate.

The present invention is directed to thin film composite membranes (TFC membranes) comprising a substrate layer (S) based on a sulfonated polyphenylenesulfone, and a polyamide film layer (F) and further to a method for their preparation. Furthermore, the present invention is directed to osmosis processes, in particular to forward osmosis (FO) processes, using said membrane.

The invention provides a membrane casting solution, an ultrafiltration membrane and a preparation method of the ultrafiltration membrane. The membrane casting solution includes: polyamide; a pore-forming additive; and a solvent, the relative molecular mass of the polyamide is 200000-300000. As a result, the viscosity of the membrane casting solution is more appropriate, and the membrane casting solution has almost no bubbles, and is conducive to film formation.

The present invention relates to a separation membrane for water treatment having high water flux and membrane contamination preventing characteristics, and a manufacturing method thereof. The separation membrane for water treatment according to the present invention includes a nanofiber wherein the separation membrane has a surface electric charge. According to the present invention, a separation membrane for water treatment having high water flux and membrane contamination preventing characteristics, and a manufacturing method thereof may be implemented.

A draw solute includes a water-soluble alkyl ammonium salt compound, the water-soluble alkyl ammonium salt compound including an ionic moiety and at least two ammonium cationic moieties, the ionic moiety including an anion selected from a carbonate anion (COO−), a sulfonate anion (SO3−), a sulfate anion (SO42−), a phosphonate anion (PO32−), and a phosphate anion (PO43−), and a cation selected from an alkali metal cation and an alkaline earth metal cation.

The invention discloses a deep treatment method of high-concentration organic wastewater. The method comprises the following steps: step one, coagulating and precipitating; step two, carrying out ultraviolet-ozone-ultrasound combined reaction stage; step three, carrying out electrolysis treatment through three dimension electrodes; step four, recycling heavy metals; and step five, carrying out ultrafiltration-electrodialysis coupled desalinization. The deep treatment method of high-concentration organic wastewater is free of biological treatment processes, free of pretreatment, high in desalinization rate, simple to operate, high in efficiency, free of secondary pollution and low in cost, and is capable of completely removing organic matters, recycling the heavy metals and recycling the high-concentration organic wastewater.

The invention discloses a method for preparing an organic-solvent-resistant ultrafiltration membrane, the prepared ultrafiltration membrane and application of the ultrafiltration membrane. The method for preparing the organic-solvent-resistant ultrafiltration membrane includes the steps of preparing a membrane casting solution, performing precipitation phase inversion, filtering and cleaning an ultrafiltration membrane for the first time, cross-linking the ultrafiltration membrane and filtering and cleaning the ultrafiltration membrane for the second time. The surface layer of the membrane is cross-linked, and a supporting layer is also cross-linked. According to the method, preparation time is short, the technology is simple, and solvents are saved. The prepared ultrafiltration membrane has the advantage of being resistant to organic solvents and has good application prospects in separation of organic solvent systems.

The invention relates to a reverse osmosis membrane, and a preparation method and application thereof. The preparation method of the reverse osmosis membrane comprises the following steps: providing a supporting membrane, and forming a polyamide layer on the surface of the supporting membrane, wherein the polyamide layer comprises acyl halide groups; and providing a mixed solution which comprises polyamine, a polar small molecule solvent and a hydrophilic polymer, placing the mixed solution on the surface, far away from the supporting membrane, of the polyamide layer, and performing heat treatment to make the acyl halide groups in the polyamide layer react with the polyamine in the mixed solution and the polyamide layer become a compact layer, so as to obtain the reverse osmosis membrane, wherein the mass fraction of the polar small molecule solvent in the mixed solution is greater than or equal to 50%, the mass fraction of the hydrophilic polymer in the mixed solution is less than or equal to 1%, and the compact layer further comprises the hydrophilic polymer. The reverse osmosis membrane prepared by the preparation method of the reverse osmosis membrane has high desalination rate and water flux, and can be better applied to a water treatment device.

The invention discloses a membrane winding structure capable of improving the flux of a reverse osmosis membrane element and a preparation method thereof. The membrane winding structure comprises a center pipe, and one port of the center pipe serves as a water inlet end; a water outlet is formed in the circumferential wall of the center pipe; the membrane winding structure also comprises at leastone layer of wound layer; the wound layer comprises a water inlet separation net; a first reverse osmosis membrane and a second reverse osmosis membrane are arranged on the upper and lower end faces of the water inlet separation net; the front surfaces of the first reverse osmosis membrane and the second reverse osmosis membrane both face the water inlet separation net; the back surfaces of the first reverse osmosis membrane and the second reverse osmosis membrane are both connected with pure water guide cloth; and the water inlet separation net, the first reverse osmosis membrane, the pure water guide cloth and the second reverse osmosis membrane are wound at the periphery of the center pipe. The preparation method comprises stacking the above parts in order and winding the parts at the periphery of the center pipe. The membrane winding structure can effectively improve the flux of the reverse osmosis membrane element and prolong the service life.

The present invention relates to systems, methods and uses for recycling at least a part of water lost during various renal replacement therapy processes, e.g. in the preparation of a fresh dialysate solution or fresh reconstitution fluid for kidney disease dialysis and hemofiltration by utilizing water from the spent fluids. The system of the invention is useful in hemodialysis and in peritoneal dialysis as well as in hemofiltration for reuse of water from filtrates and spent fluids. In addition, the system of the invention is useful in the development of a renal assist device or artificial kidney.

The invention relates to a preparation method for a cellulose acetate forward osmosis membrane, and belongs to the technical field of membrane separation. The preparation method comprises the steps that dried cellulose acetate powder is dissolved in mixed organic solvent, and the mixture is put into a water bath to be mechanically stirred to form a uniform solution; the solution is put into a vacuum environment for standing and defoaming to form a membrane casting solution; the membrane casting solution is poured on a clean glass board and uniformly applied on the glass board with a scraper; the surface of the membrane casting solution is covered with a polyester screen immediately, and the membrane casting solution is quickly transferred into a baking oven for volatilization; the glass board with the membrane casting solution is put into a flowing deionized water gel bath; a regenerative membrane piece is stripped from the glass board and then put into a water bath at the temperature of 50 DEG C-90 DEG C, and the cellulose acetate forward osmosis membrane is obtained. The preparation method is simple in technology and easy to operate, and the prepared membrane is excellent in mechanical performance and high in water flux and has the higher salt intercepting rate and the lower inner concentration polarization phenomenon.

The invention discloses a deep treatment method of high-salt organic sewage. The method comprises the following steps: step one, carrying out pretreatment; step two, carrying out electroflocculation and precipitation; step three, carrying out ultraviolet-ozone-ultrasound combined reaction stage; step four, carrying out electrolysis treatment through three dimension electrodes; step five, filteringthrough three-dimensional graphene sponge; and step six, carrying out ultrafiltration-electrodialysis coupled desalinization. The method is free of biological treatment processes and high in processflexibility; compared with the common sewage treatment method, the treatment period is greatly shortened; meanwhile, the method is high in desalinization rate, simple to operate, high in efficiency, free of secondary pollution and low in cost, and is capable of completely removing organic matters, recycling the heavy metals and directly recycling the treated high-salt organic sewage.

The invention discloses a preparation method of a molybdenum disulfide nano dot hybrid nano-filtration membrane. The preparation method comprises the following steps: obtaining a hydrolyzed polyacrylonitrile ultra-filtration membrane from a polyacrylonitrile ultra-filtration membrane; dispersing amino-containing MoS2 nano dots in a piperazine aqueous solution to prepare a water phase, and dissolving trimesoyl chloride in normal hexane to prepare an organic phase; and soaking the hydrolyzed polyacrylonitrile ultra-filtration membrane in a water phase, taking out the hydrolyzed polyacrylonitrile ultra-filtration membrane, removing water drops on the surface of the membrane by using dust-free absorbent paper, then soaking the hydrolyzed polyacrylonitrile ultra-filtration membrane in an organic phase, taking out the hydrolyzed polyacrylonitrile ultra-filtration membrane, washing the hydrolyzed polyacrylonitrile ultra-filtration membrane by using normal hexane, and finally carrying out thermo-curing and filter pressing to obtain the MoS2 nano dot hybrid nano-filtration membrane. The preparation method is simple and convenient to operate and convenient to implement, the separation layer forms a rapid water transmission channel due to hybridization of the MoS2 nano dots, the separation layer has good water flux, meanwhile, the rejection rate of divalent salt is kept, and the rejection rate of mono-valent salt is reduced. The hybrid nano-filtration membrane prepared by the invention is applied to salt-containing wastewater resourceful treatment, and has relatively high water flux and salt resourceful utilization efficiency.

The invention, belonging to the field of membrane technology, presents a method for the high-throughput preparation of carbon nanotube hollow fiber membranes. This method contains three major steps. Firstly, the pristine carbon nanotubes (CNTs) are added into a mixture of concentrated nitric acid and sulfuric acid, which is then heated at 40˜80° C. for 0.5˜6 hours. Secondly, the surface-functionalized CNTs and polyvinyl butyral (PVB) are dispersed and dissolved, respectively, in organic solvents at a mass ratio of 1:0.2˜1:4˜8 to form homogeneous spinning solution, which is squeezed into water as shell liquid with water as core liquid at a flow rate ratios of 0.5˜5:1 through a spinneret to form CNT / PVB hollow fibers. Finally, the dry fibers are calcinated at 600˜1000 ° C. for 1˜4 hours in absence of oxygen to produce free-standing CNT hollow fiber membranes. The method involved in this invention is simple and highly efficient without needing any templates, expensive apparatuses and chemicals. Additionally, the obtained electrically conductive CNT hollow fiber membranes feature a high porosity, high water flux and strong acid / alkali resistance.

A semi-permeable membrane may include a support layer and an active layer in contact with the support layer. The support layer includes a porous structure including a polymer and at least one metal (or metalloid) oxide in the porous structure. In the support layer, the amount of the metal (or metalloid) oxide present in a portion adjacent to the active layer is higher than the amount of the metal (or metalloid) oxide present in a portion farther from the active layer.

A draw solute including an oligomer having an amino acid repeating unit with an ionic moiety and a counter ion thereof, and a forward osmosis water treatment device and method using the same are provided.

The present invention is directed to thin film composite membrane (TFC membrane) comprising a substrate layer (S) based on a sulfonated polymer, e.g. a sulfonated polyarylether, and a polyamide film layer (F) and further to a method for their preparation. Furthermore, the present invention is directed to osmosis processes, in particular to forward osmosis (FO) processes, using said membrane.

The invention relates to a method for synthesizing an A type molecular sieve membrane at a low temperature. The method comprises the following steps: crystallizing a silicon source, an aluminum source, an alkali and water to prepare an A type molecular sieve nano-seed crystal; preparing a synthetic mother liquor from the silicon source, the aluminum source, the alkali and water; and coating a carrier with the A type molecular sieve nano-seed crystal, placing the carrier in the synthetic mother liquor, and carrying out hydrothermal crystallization at 20-45 DEG C for 2-10 d to obtain the ultrathin A type molecular sieve membrane. The size of the molecular sieve crystal synthesized in the present invention is reduced from 1 [mu]m to about 300-500 nm, so the thickness of the membrane is reduced to about 1 [mu]m, and the permeation flux is high. In addition, the reduction of the crystallization temperature can slow down the formation process of the molecular sieve membrane and facilitate the cross-linking between the molecular sieve crystals, so generated defects are reduced, and the separation selectivity is high. The synthesis of the A type molecular sieve membrane at room temperaturemakes the synthesis process consume no energy, so energy saving and environmental protection are benefited. The synthesized A type molecular sieve membrane has a high flux and a high separation coefficient in solvent dehydration.

The invention relates to a preparation method of a hollow fiber composite nano-filtration membrane. According to the method, a polysulfone hollow fiber basic membrane is adopted and is subjected to dip-coating in a membrane forming solution, which takes acrylic resin, carboxyl type vinyl chloride-vinyl acetate resin and diphenylmethane diisocyanate as solutes and butyl acetate and dimethyl carbonate as solvents, to form a dense membrane, so as to prepare the hollow fiber composite nano-filtration membrane; the disadvantages that an organic hollow fiber composite nano-filtration membrane is easy to swell and has low mechanical strength, and an assembly is difficult to seal are overcome; meanwhile, the nano-filtration membrane has a good desalting rate and relatively high water flux and chemical stability, and can realize continuous industrial production.

Disclosed is a vesicle comprising polystyrene-polyacrylic acid (PS-PAA) block copolymer and an amphiphilic functional molecule. The vesicle is stable even at elevated temperatures and the amphiphilic functional molecule remains active. Also discloses is a selectively permeable membrane comprising a support layer and a selective layer incorporating the vesicles.

The invention discloses a reverse osmosis element and a preparation method thereof. The reverse osmosis element comprises a central pipe and at least one reverse osmosis membrane group, wherein one end of the central pipe is a water inlet end, water outlets are formed in the peripheral wall of the central pipe, and the reverse osmosis membrane group comprises a water inlet partition net, a first reverse osmosis membrane piece, pure water guide cloth and a second reverse osmosis membrane piece; one end of the water inlet partition net is connected with the peripheral wall of the central tube, the front surface of the first reverse osmosis membrane piece is connected with the water inlet partition net, the first end surface of the pure water guide cloth is connected with the reverse surfaceof the first reverse osmosis membrane piece in a matched mode, and the reverse surface of the second reverse osmosis membrane piece is connected with the second end surface of the pure water guide cloth cooperatively; and the water inlet partition net, the first reverse osmosis membrane piece, the pure water guide cloth and the second reverse osmosis membrane piece are wound around the outer circumference of the center tube. Through the reverse osmosis element, the service life of the reverse osmosis element can be improved effectively.

The invention relates to a boron-doped microporous silicon dioxide film for seawater desalination or high-salinity wastewater desalination treatment and a preparation method thereof. Aiming at the defects of the existing membrane desalination technology, organosilane is used as a precursor, a sol-gel technology is adopted to dope a nonmetal boron element under the action of an acid catalyst in synthetic sol, and the high-performance boron-doped microporous silicon dioxide film with thermal stability is prepared on a porous carrier by a dip-coating method. The method is simple in preparation process and easy to operate, and has good repeatability. The boron-doped silicon dioxide film has excellent pervaporation desalination performance, has high water flux and desalination rate at room temperature, shows excellent long-time hydrothermal stability, is particularly suitable for high-concentration seawater or high-salinity wastewater which is difficult to treat by a reverse osmosis membrane technology, can meet the requirement of large-scale industrial application, and also provides a new strategy for efficient and safe desalination application of a membrane method.

The invention provides a hollow fiber ultrafiltration membrane, belonging to the technical field of membrane separation. The hollow fiber ultrafiltration membrane is prepared from the following raw materials in parts by mass: 10-20 parts of poly-m-phenylene isophthalamide fibers, 0.1-10 parts of lithium chloride, 64-90.1 parts of an organic solvent; and the thickness of the hollow fiber ultrafiltration membrane is 0.25mm-0.32mm, the bore diameter is 30nm-50nm, the porosity is 70%-85%, and the surface contact angle of the membrane is 60-75 degrees. According to the hollow fiber ultrafiltrationmembrane, the poly-m-phenylene isophthalamide fibers have hydrophilia and are unlikely to be polluted in the operation process of the membrane. The hollow fiber ultrafiltration membrane is relativelyhigh in BSA reject rate, water flux and operation temperature.

A method for preparing a composite multilayer porous hollow fiber membrane and the device and product thereof. The method comprises preparing uncured porous hollow fibers with larger pore diameters as the inner supporter of the membrane from thermoplastic macromolecule polymer resins by thermal induced phase separation method and then bonding a superthin coating layer with microfiltration or nanofiltration function and small pore diameter prepared on the outer surface of the hollow fibers from a solution of the thermoplastic macromolecule polymer resins by a coating process using non-solvent induced phase separation method. The composite multilayer porous hollow fiber membrane has such excellent mechanical strength and high water flux as the membranes prepared by thermal induced phase separation method, such high precision filter effect and high contamination resistance as the membranes prepared by non-solvent induced phase separation method, and high binding force of the membrane prepared by the above method.

The invention discloses water purification equipment with a taste adjusting function, and belongs to the technical field of water treatment. The water purification equipment comprises a softener and a raw water pump, the raw water pump is arranged on the right side of the softener, and an ultrafiltration membrane, a first activated carbon filter, a reverse osmosis membrane, a pure water tank, a constant-pressure water supply pump and a second activated carbon filter are further arranged on the right side of the raw water pump; a purified water outlet of the ultrafiltration membrane is connected with a first activated carbon filter, a purified water outlet of the first activated carbon filter is connected with a reverse osmosis membrane, and a purified water outlet of the reverse osmosis membrane is connected with a purified water tank; a concentrated water outlet of the ultrafiltration membrane, a concentrated water outlet of the first activated carbon filter and a concentrated water outlet of the reverse osmosis membrane are all connected with a first electromagnetic valve; a constant-pressure water supply pump and a second activated carbon filter are also arranged on the right side of the purified water tank. The equipment is convenient to install, simple in structure, economical, durable, high in reliability, long in service life and good in stability, adopts a solid structure and is free of movable parts.