4813results about "Membranes" patented technology

The invention provides a PVDF (Polyvinylidene Fluoride) nanofiltration membrane constructed on the basis of microwave-enhanced bridging interfacial polymerization as well as a preparation method and application of the PVDF nanofiltration membrane. The method comprises the following steps: reacting PVDF powder with an organic alkali to prepare a modified film-forming solution, blade-coating the modified film-forming solution on a non-woven fabric supporting layer, placing the non-woven fabric supporting layer in an ethanol-water or methanol-water coagulating bath, and preparing a PVDF supporting film by virtue of assistance of an ice template; weighing the functionalized nano material and an amino silane coupling agent, performing ultrasonic dispersion, and adding a catalyst for reaction to obtain dispersion liquid; immersing a PVDF support membrane into the dispersion liquid to obtain a modified membrane; immersing the modified membrane into an aqueous solution containing an amine monomer and an organic solution containing an acyl chloride monomer, and carrying out microwave radiation. The interface reaction rate and selectivity are enhanced through the microwave excitation effect, and meanwhile, the hydrophilicity and reaction activity of the PVDF base membrane are cooperatively regulated and controlled, so that the separation efficiency and the anti-pollution capacity of the membrane are remarkably improved. The obtained PVDF nanofiltration membrane has high flux, high selectivity and excellent structural stability, and is suitable for efficient purification and resource recovery application in a complex water system.

The present disclosure relates to a carbon dioxide capture apparatus and process combined with biogas upgrading, and there is provided the carbon dioxide capture apparatus combined with biogas upgrading for simultaneously obtaining high purity methane and carbon dioxide, and improving separation efficiency without an additional process by making use of gas streams after a liquefaction process, and recovering cold heat in the process.

The application provides application of a temperature-sensitive composite material in preparation of a separation membrane, a nanofiltration membrane and a preparation method, and particularly relates to the technical field of separation membranes. The temperature-sensitive composite material comprises a temperature-sensitive material and conductive fillers. The mass ratio of the temperature-sensitive material and the conductive fillers is 10-30:1-10. The application utilizes the characteristic that the temperature-sensitive material quickly responds to temperature changes, and the temperature-sensitive material transmits to the outside world through the conductive fillers, so that timely feedback and adjustment of the temperature in the preparation process of the separation membrane are realized, the isotropic separation membrane is prepared, the stability of the performance of the separation membrane is ensured, and the quality of the separation membrane product is improved.

This invention discloses a method for preparing an amphoteric Janus nanofiltration membrane. First, dopamine hydrochloride is dissolved in a mixed solution of tert-butyl hydroperoxide and Tris buffer solution. Then, a nylon-based membrane is immersed in the dopamine solution to modify its surface. Next, a dual-nozzle electrospinning device is used to electrospray tert-butyl hydroperoxide in ethanol solvent and 1,3,5-benzenetricarbonyl trichloride in 2-methyltetrahydrofuran onto one side of the dopamine-modified membrane, forming a positively charged active layer. The spraying solutions are then changed to tetraethylenepentamine in ethanol solvent and 1,3,5-benzenetricarbonyl trichloride in 2-methyltetrahydrofuran, and the same spraying parameters are used to electrospray the other side of the dopamine-modified membrane to form a negatively charged active filtration layer. The resulting membrane is then vacuum-dried and thermosetting to obtain the amphoteric Janus nanofiltration membrane. The prepared amphoteric Janus nanofiltration membrane has positive and negative charges on both sides, respectively. When different sides are used, it has a good filtration effect on anionic or cationic dyes in wastewater and has a high water flux.

The invention provides a nylon 6 nanofiber virus-removing filtering membrane and a preparation method and application thereof.The nylon 6 nanofiber virus-removing filtering membrane comprises a base material and a nylon 6 nanofiber membrane compounded to the surface of the base material, the average pore size of the virus-removing filtering membrane is 20 nm, the virus-removing filtering membrane plays a role in blocking parvoviruses, the surface of the virus-removing filtering membrane is charged, and the surface of the virus-removing filtering membrane is not prone to being damaged. Proteins with the same charges on the surface can be prevented from adhering to the surface of the fiber. In the preparation process of the virus-removing filtering membrane, the nylon 6 nanofibers with a certain diameter range are selected and compounded on the surface of the base material in a stable dispersion state, the uniform microporous virus-removing filtering membrane is prepared, the effect that parvoviruses are blocked and protein molecules are not easily intercepted is achieved, the hydrophilicity of the nylon 6 nanofibers is relatively good, and the virus-removing filtering membrane has a good application prospect. The non-specific adsorption of the filtering membrane on the protein is reduced; the nylon 6 nanofiber virus-removing filtering membrane can be applied to the field of biological medicine products, and has important significance on separation and purification of biological preparations.

The invention discloses a seawater desalination treatment system and method based on a penetration method, and particularly relates to the technical field of seawater desalination treatment.The seawater desalination treatment system is provided with an online monitoring module, and various indexes in the seawater desalination treatment process are monitored through a multi-source sensor; a seawater pollution treatment module is arranged to remove suspended particles and pollutants in seawater; a seawater desalination treatment module is arranged for deep desalination; setting an equipment management module to judge whether equipment maintenance is needed or not based on the real-time operation data of the equipment; a semi-permeable membrane loss prediction module is arranged for semi-permeable membrane loss prediction; setting a semi-permeable membrane maintenance control module to automatically match a corresponding maintenance strategy according to the predicted membrane loss degree; a forward osmosis and reverse osmosis coupling process is combined, so that the desalination rate and the energy consumption efficiency ratio are improved, and the service life of the semipermeable membrane is effectively prolonged; an intelligent monitoring-prediction-control system is constructed, and the stability and reliability of the technological process are guaranteed.

This disclosure relates to the fabrication of high-performance thin film composite (TFC) reverse osmosis (RO) membranes comprising a thin polyamide rejection layer (thickness of 100-200 nanometer), a porous substrate including polysulfone (PSf) layer (thickness of 40-50 micron) cast on polyester nonwoven fabric (thickness of ˜100 micron). Hydrophilic and antibacterial TFC polyamide RO membranes were developed by incorporating green Lignin and nanostructured silver-based metal organic frameworks (MOFs) into the selective layer. The polyamide layer of TFC RO membranes was fabricated on the porous PSf substrate by interfacial polymerization between aqueous monomer solutions containing MPD, and adequate additives in water and organic monomer solutions containing TMC in the mixture of hexane and co-solvents. The optimized produced RO membranes were provided water flux of 95-100 LMH and sodium chloride (NaCl) salt rejection of 98.5-99.0% during filtration of 2000 ppm NaCl solution at 225 psi pressure, and water flux of 55-60 LMH and sodium chloride (NaCl) salt rejection of 98.6-98.9% during filtration of 35000 ppm NaCl solution at 800 psi pressure. This disclosure also relates to developing a roll-to-roll PSf membrane as a substrate for making TFC RO membranes for water desalination

The present invention relates to a method for automated data processing to assess the state of multiple filtration membranes used in liquid filtration. The method involves receiving data from state sensors positioned within or near a set of membranes, which process incoming water into permeate and concentrate flows. This data, collected as time series at predefined frequencies, pertains to external physical parameters. An operating indicator is determined from this data, forming a second time series. Both the first and second time series are recorded as point clouds over a specified acquisition period. An intermediate operating indicator is generated, representing the state of new, clean, or cleaned membranes, using a learned normalization model. Finally, a normalized operating indicator is produced, characterizing membrane fouling and aging, independent of environmental variations, and forming a third time series. This method enhances the accuracy of membrane state assessment in filtration systems.

The invention discloses a crown ether grafted polyarylether sulfone ion separation membrane as well as a preparation method and application thereof, and belongs to the technical field of ion separation membranes, collaborative optimization is realized through crown ether accurate grafting and ultrathin ordered membrane formation: a main chain of polyarylether sulfone is grafted with 4 '-aminobenzo-12-crown-4 to form an inherent channel adapted to Li, and the specific surface area of the main chain is increased; the ultrathin film is prepared by a water surface spreading method, and the ion transmission path is shortened. Finally, in a LiCl / MgCl system, Liion flux has high selectivity, high permeation-high selectivity cooperation is preliminarily realized, the chemical synthesis step can be amplified to a kilogram level, and after a DPAES-g-CE / dichloromethane solution is dropwise added to the water surface, the DPAES-g-CE / dichloromethane solution is rapidly spread to form a film without precise equipment; the raw materials are industrial-grade monomers and have no toxic residues, the membrane can be recycled and reused through dichloromethane, the equipment cost is reduced by about 90%, and industrialization is easy; the main chain of the polyaryl ether sulfone is high in rigidity and resistant to high temperature and chemical corrosion; crown ether grafting avoids molecular chain agglomeration, and the swelling rate is far lower than that of a traditional sulfonated membrane.

A membrane includes a polysulfone-based support, a polydopamine (PDA) layer disposed on a surface of the polysulfone-based support, and a silver / polydopamine (Ag / PDA) composite layer disposed on a surface of the polydopamine layer. The polysulfone-based support has a pore size of up to 600 nanometers (nm). The Ag / PDA composite layer contains core-shell structure particles and spherical particles. The core-shell structure particles have a silver nanoparticle core and a polydopamine shell. The spherical particles are silver-decorated polydopamine particles. The membrane can at least partially separate an Erichrome Black T (EBT) dye from an EBT dye / salt containing mixture by rejecting the EBT dye and allowing the EBT dye / salt containing mixture to pass through the membrane.

A membrane made of a polymeric support, and an active layer with a polyamide grafted with a copolymer on the polymeric support. The copolymer is reacted units of a diallyldimethylammonium chloride (DADMAC), 3-(N,N-diallyl-N-methylammonio)propanesulfonate (DAMAPS), and N,N-diallyldodecane-1,12-diamine (DADA), and the copolymer is grafted to the polyamide with a linking molecule. Further, a method of making the membrane by dissolving an amine and the copolymer in water to form an aqueous solution, dissolving TMC in an organic solvent to form an organic mixture, pouring the aqueous solution onto a polymeric support and then pouring the organic mixture onto the same support for form a coated support, and heating the coated support to form a membrane.

The invention belongs to the technical field of membrane separation, and particularly relates to a recrystallized silicon carbide ceramic nanofiltration membrane as well as a preparation method and application thereof. The preparation method comprises the following steps: applying a polycarbosilane solution to a silicon carbide ceramic ultrafiltration body, and carrying out first pyrolysis to obtain a pyrolysis material; a polycarbosilane solution is applied to the pyrolysis material, and then second pyrolysis is carried out; the first pyrolysis process comprises the following steps: heating to 290-310 DEG C from room temperature, and preserving heat; raising the temperature from 290-310 DEG C to 790-810 DEG C, and keeping the temperature; raising the temperature from 790 to 810 DEG C to 1190 to 1210 DEG C, and keeping the temperature; the second pyrolysis comprises first pyrolysis and recrystallization which are carried out in sequence; the recrystallization process comprises the following steps: heating from 1190-1210 DEG C to 1590-1610 DEG C, and preserving heat; the temperature is increased to 2190-2210 DEG C from 1590-1610 DEG C, and heat preservation is conducted. The aperture of the recrystallized silicon carbide ceramic nanofiltration membrane is smaller than 10 nm, and nanofiltration can be achieved.

A system for separating a gas mixture is provided. The system includes a source of a gas mixture and a membrane separation stage including a gas separation membrane module. The membrane separation stage is in fluid communication with the source of the gas mixture, and the gas separation membrane module is configured to separate the gas mixture into a retentate stream and a permeate stream. The gas separation membrane module also includes a membrane having a permeate side and a retentate side. A sweep stream is provided to the permeate side of the membrane, the sweep stream comprising a portion of the retentate stream.

The invention discloses a super-strong sulfuric acid-resistant nanofiltration membrane as well as a preparation method and application thereof. The super-strong sulfuric acid-resistant nanofiltration membrane comprises a base membrane and a separation layer formed on the upper surface of the base membrane, the separation layer is formed by carrying out interfacial polymerization reaction on a water phase solution and an organic phase solution and then carrying out heat treatment; the solute of the water phase solution comprises at least one of piperazine, m-phenylenediamine, p-phenylenediamine, ethylenediamine and polyethyleneimine; the solute of the organic phase solution comprises at least one of trimesoyl chloride, paraphthaloyl chloride and isophthaloyl chloride; the base membrane is made of at least one of polysulfone, polyether sulfone, polyacrylonitrile, polytetrafluoroethylene and polyvinylidene fluoride; the solute of the organic phase solution also comprises toluene diisocynate. Appropriate monomers are selected, so that a polyamide main chain or a side group has the characteristic of acid hydrolysis resistance; and by controlling the monomer concentration, the reaction time and the temperature, the crosslinking degree and the compactness are optimized, and the acid-resistant stability is enhanced while the high rejection rate is ensured.

The invention belongs to the field of wet electronic chemical purification, and particularly relates to a membrane chromatography filter membrane for removing charged ions in liquid and a preparation method thereof.The preparation method comprises the following steps that S1, membrane casting liquid is prepared, specifically, a positive electricity layer membrane casting liquid, a neutral layer membrane casting liquid and a negative electricity layer membrane casting liquid are prepared; s2, sequentially extruding the positive electricity layer membrane casting solution, the neutral layer membrane casting solution and the negative electricity layer membrane casting solution by using a three-layer die head, and coating on a polyester film; s3, exposing under the conditions of set temperature, humidity and air velocity, so that the casting membrane solution is subjected to preliminary phase splitting; s4, immersing the coated film in a pure water coagulating bath to complete phase splitting and curing; and S5, rinsing, drying and rolling to obtain the membrane chromatography filter membrane. By designing a special three-layer composite structure of'positive electricity layer-neutral layer-negative electricity layer ', the filter membrane can simultaneously adsorb anions and cations in a solution in a single filtering process, the limitation that a traditional single charge membrane can only remove one kind of ions is solved, and the purification efficiency is improved.

A method of preparing a polyamide membrane with multi-level pore structure mediated by protein fiber network includes the steps of: preparing protein fiber; quenching and carrying out dialysis; loading protein fiber network on ultrafiltration membrane; preparing aqueous and organic phase solutions; and carrying out interfacial polymerization, which can solve the problems of the integrity and separation performance of the polyamide layer being affected by low porosity of the base membrane and uneven distribution of amine monomers. The polyamide membrane prepared by the method of the present invention greatly improves the water flux while ensuring a high salt rejection rate. At the same time, the introduction of the protein fiber network also enhances the mechanical strength and anti-pollution ability of the membrane.

A separation membrane, a preparation method therefor and a use thereof in magnesium and lithium separation are provided. The separation membrane includes, in sequence, a base material layer, a porous support layer, a polyamide layer and a modification layer. Cross-linked polymers forming the modification layer has structural units provided by polyphenols and polyamines, at least some of the structural units provided by the polyphenols are connected to the polyamide layer via ortho positions of phenolic hydroxyl groups. The preparation method includes sequentially preparing the porous support layer, the polyamide layer and the modification layer on the base material layer. The method of preparing the modification layer includes under a first pressure, bringing one side of the polyamide layer into first contact with the polyphenol solution; then under a second pressure, bringing one side of the polyamide layer into second contact with the polyamine solution, to complete a self-assembly reaction.

The invention discloses a self-cleaning composite piezoelectric ceramic membrane as well as a preparation method and application thereof, and belongs to the field of composite ceramic membranes. The technical problem that an existing ceramic membrane separation technology is poor in biomembrane pollution resisting effect is solved. According to the preparation method, the barium titanate ceramic membrane is firstly prepared to serve as the base membrane, then the copper oxide one-dimensional nanostructure is loaded on the piezoelectric ceramic substrate, and the base membrane has a large membrane surface area and can be combined with more catalysts, so that more active sites are provided for catalytic reaction; according to the composite membrane, the hydrophilicity, the anti-pollution performance and the piezoelectric catalysis self-cleaning performance of the membrane are remarkably improved, and pollutants in water can be quickly and effectively separated, so that the flux and the anti-pollution performance of the membrane are improved.

Disclosed are multi-cartridge hollow fiber membrane apparatuses and methods for gas separation using them. Each external pressure type membrane apparatus contains one or more series of cartridges wherein the cartridges within each series are arranged sequentially. The retentate gas generated by each preceding cartridge in the series is used as a feed gas to the next cartridge in the series, and the permeate gas generated by a cartridge following the first cartridge in the series is used as a sweep gas on the permeate side of the preceding cartridge. The multicomponent gas mixture is separated into one or more products by the method of the invention with improved product recovery and / or product purity.

Membranes and related systems and methods for separation of components in liquids are generally described. The membrane may include particles in a polymer matrix (e.g., a polyamide layer). The particles may include metal-organic framework particles comprising functional groups (e.g., from post-synthetic modification) that can, in some instances, improve the rejection and / or selectivity of the membrane. For example, the metal-organic framework may comprise functional groups bound to hydrophobic groups (e.g., alkyl chains) that assist with suspension stability in nonpolar solvents during membrane fabrication. As another example, the metal-organic framework may comprise functional groups bound to crosslinking agents that facilitate in situ crosslinking of the particles with the polymer matrix, thereby reducing voids in the membrane and / or leaching. In some instances, the membrane is a thin-film nanocomposite membrane (e.g., for separating components like charged species and / or neutral species) formed via, for example, interfacial polymerization in the presence of the particles.

The invention discloses a mixed matrix membrane for efficient oxygen and nitrogen separation and a preparation method and application thereof. The mixed matrix membrane comprises a polymer continuous phase and an MOF filler uniformly dispersed in the polymer continuous phase, the MOF filler can separate nitrogen and oxygen, and the surface of the MOF filler is modified by the silane coupling agent, so that the MOF filler is well compatible with a polymer, and the oxygen-nitrogen separation effect is improved. The polymer solution and the MOF filler dispersion liquid are mixed, the mixed matrix membrane is prepared through the non-solvent induced phase separation method, and the method has the advantages of being simple in reaction condition, high in efficiency, easy to amplify and the like and has wide engineering prospects.

The present invention relates to a fuel cell membrane humidifier which can actively control the flow rate of exhaust gas flowing from a fuel cell stack according to the output condition of a fuel cell. A fuel cell membrane humidifier according to one embodiment of the present invention includes a mid-case having an inlet through which wetting gas supplied from the fuel cell stack is introduced and an outlet through which the wetting gas is discharged; a cartridge disposed inside the mid-case and accommodating a plurality of hollow fiber membranes; a bypass space formed in the space between the mid-case and the cartridge; and an active blocking member for controlling the degree of opening of the bypass space according to the temperature of the wetting gas introduced through the inlet.

The application discloses a preparation method of a hydrophilic oil-water separation anti-pollution membrane and the anti-pollution membrane and application thereof, and prepares MNRs material; the MNRs material is dispersed in dimethylacetamide, is uniformly stirred, polyvinylpyrrolidone is added, and stirring is continued, and a first mixture is obtained through ultrasonic treatment; the first mixture is mixed with polyvinylidene fluoride to obtain a second mixture, and the second mixture is stirred; the treated second mixture is dip-coated on a carrier, the dip-coated carrier is treated in deionized water to obtain an ultrafiltration membrane; the ultrafiltration membrane is soaked in a tea polyphenol solution with a Tris-HCl buffer solution, and is shaken to obtain the hydrophilic oil-water separation anti-pollution membrane. The hydrophilic oil-water separation anti-pollution membrane has excellent separation efficiency and flux recovery rate for four different oil-water mixtures of kerosene, gasoline, edible oil and n-hexane. The preparation process of the oil-water separation membrane is simple, the cost is low, and the reaction condition is mild; when the oil-water separation membrane is applied to organic wastewater separation, the oil-water separation membrane has the advantages of high efficiency, good removal performance and good recycling performance.

The invention belongs to the technical field of semipermeable membrane preparation, and particularly relates to a preparation method of a nanofiltration membrane. The preparation method comprises the following steps: (1) cleaning the supporting layer for later use; the preparation method comprises the following steps: blending diamine, an amino beta-cyclodextrin derivative, an inorganic hybridizing agent, a zwitterionic compound and water to obtain a water phase for later use; blending aromatic acyl chloride, a cosolvent and an organic solvent to obtain an oil phase for later use; and (2) sequentially carrying out primary impregnation in a water phase, membrane scraping, secondary impregnation in an oil phase and heating curing on the supporting layer, and finally carrying out post-treatment to obtain the nanofiltration membrane. The nanofiltration membrane is prepared by introducing the amino beta-cyclodextrin derivative, the inorganic hybridization agent and other components into polyamide, so that the water flux of the polyamide nanofiltration membrane and the capability of effectively separating ions with different valence states are further improved.

The invention discloses a preparation method and application of an amino-functionalized graphene quantum dot modified MXene loose nanofiltration membrane. The preparation method comprises the following steps: mixing an MXene nanosheet dispersion liquid with an aminated graphene quantum dot aqueous solution, and preparing an amino functionalized graphene quantum dot / MXene mixed dispersion liquid by adopting a self-assembly method; and filtering and depositing the obtained mixed dispersion liquid on the modified base membrane to obtain the MXene loose nanofiltration membrane. According to the preparation method disclosed by the invention, the zero-dimensional aminated graphene quantum dots are creatively embedded into the MXene nanosheets, so that the MXene loose nanofiltration membrane which is stable in structure and regular in stacking is prepared. The nanofiltration membrane has good separation performance on different dyes and inorganic salts while effectively inhibiting water swelling, is a next-generation separation membrane with high stability and high selectivity, is mild and simple in preparation process, and has a wide application prospect.

The invention relates to a water treatment and membrane separation technology, and provides an integrated catalytic separation membrane, a preparation method thereof, and a water treatment method and system. According to the membrane, polyvinylidene fluoride is used as a continuous phase to form a porous matrix, and cerium dioxide is embedded and fixed in a mode of uniform dispersion in a membrane body in a phase inversion membrane forming process; in the presence of illumination and peroxysulfate, active species are generated through in-situ activation on a membrane-water interface, and membrane separation is completed synchronously. The water treatment method comprises the following steps: adding peroxymonosulfate or peroxydisulfate into a water body to be treated, and filtering through the membrane under illumination; the photothermal effect generated by organic matter degradation intermediates in operation inhibits membrane pollution and maintains flux. According to the invention, short-range coupling of active sites and mass transfer channels is realized, the medicament and energy utilization rate is improved, the coating stripping and metal dissolution risk is reduced, and the method is suitable for drinking water pretreatment, reclaimed water deep treatment and treatment of water containing natural organic matters / humic acid.

An exchange fluid having one or more amino acid for removing carbon dioxide from a solid sorbent and systems containing the same are disclosed. The exchange fluid may further include a neutralizing base for neutralizing the amino acid. The system may further employ an electrochemical cell to regenerate the exchange fluid by removing carbon dioxide from the exchange fluid without employing degrading temperatures and pressures.

The invention belongs to the technical field of membrane separation, and particularly relates to a low-pressure high-flux polyamide / polysulfone hollow fiber composite nanofiltration membrane and a preparation method thereof. The preparation method of the composite nanofiltration membrane comprises the following steps: dissolving sulfonated polysulfone, poly (1-vinyl-3-butylimidazole) bromide and polyvinylpyrrolidone to prepare a spinning solution, and spinning to obtain a base membrane; carrying out hydrophilic modification on the base membrane by using 1, 3-propane sultone; then, an aqueous phase solution containing poly (gamma-glutamic acid) and triethylene tetramine and an organic phase solution containing trimesoyl chloride and 3, 5-diaminobenzoic acid are subjected to interfacial polymerization in the inner cavity of the modified base membrane to form a polyamide separation layer; and finally, carrying out heat treatment to obtain the composite nanofiltration membrane. Through the synergistic effect of zwitterionic ionization of the base membrane and biomacromolecule construction of the separation layer, the mass transfer resistance of water is remarkably reduced, unification of high flux and high selectivity is achieved, and good structural stability is achieved.