3361results about "Reverse osmosis" patented technology

The invention provides a method and a system for intelligently interactively controlling water production equipment. Wherein heavy metal ion concentration data is collected in real time through a multi-node sensing array, concentration difference fluctuation of adjacent monitoring points is analyzed, and a pollutant diffusion track is deduced; when the monitoring data exceeds the standard, switching of a standby water source is triggered based on a diffusion trajectory analysis result, and a reverse cleaning instruction is generated in combination with the dynamic ratio of the concentration gradient change rate to the diffusion speed; dynamically correcting the concentration deviation by utilizing fluid mechanics parameters in a high-pressure impact process in cooperation with multi-dimensional sensor data, and generating environmental response type pollution grade parameters; finally, a pollutant migration path in the three-dimensional diffusion model is matched according to the pollution level, a decision signal containing emergency water source coordinates and the cleaning priority is output, and full-process closed-loop intelligent control from pollution monitoring to emergency decision is achieved. According to the technical scheme provided by the invention, the response speed and the disposal accuracy of the water quality sudden pollution event are improved.

The invention relates to the technical field of water resource purification, in particular to a control method and equipment of a reverse osmosis water purification system.The control method comprises the steps that firstly, on the fluctuation dimension of the pre-membrane pressure, the adjusting requirement of the frequency of a high-pressure pump is preliminarily determined on the dimension of the pre-membrane pressure according to an obtained pressure fluctuation index; determining a membrane resistance increase factor representing the pollution state of the reverse osmosis membrane on the basis of the transmembrane pressure difference on the dimension of separation function failure of the reverse osmosis membrane; finally, a membrane separation abnormal value is comprehensively represented by combining a pressure fluctuation index and a membrane resistance increase factor, and a purified water recovery rate is introduced to a membrane separation result end, so that the finally obtained frequency reduction demand degree is more accurate, and the control effect of the reverse osmosis water purification system is improved; therefore, the stable, efficient and sustainable operation of the reverse osmosis water purification system can be ensured while the membrane surface pollutant deposition driving force can be effectively reduced and the membrane pollution speed can be slowed down.

The invention discloses an energy-saving and consumption-reducing method for a reverse osmosis membrane system, which belongs to the technical field of water treatment and comprises the following steps: step 1, acquiring various parameter data of the reverse osmosis membrane system in real time; 2, establishing an energy consumption prediction mathematical model of the reverse osmosis membrane system; 3, inputting the real-time parameter data into the energy consumption prediction mathematical model, and judging whether the operation power of the high-pressure pump is reasonable or not according to an output result; 4, when the operation power is not reasonable, the operation power of the high-pressure pump is adjusted in real time; and 5, establishing a membrane pollution concentration early warning model, and carrying out alarm response. According to the method, comprehensive analysis can be carried out in real time according to various parameters of inflow water quality to accurately predict the predicted power, so that whether the set operation power of the high-pressure pump is reasonable or not is judged, the operation power of the high-pressure pump can be dynamically adjusted, the output of energy consumption can be reduced as much as possible under the condition that treatment is qualified, and the operation efficiency of the high-pressure pump is improved. And the cost is saved.

The invention discloses a preparation method of an acid-resistant polyquaternary ammonium membrane based on a Porxitch interfacial polymerization reaction. The preparation method comprises the following steps: dissolving an amine monomer in a water-phase solvent to form a water-phase solution; dissolving a bromomethyl monomer in an organic phase solvent to form an organic phase solution; after the base membrane is soaked in the water phase solution for a period of time, the water phase solution is removed, and the water phase solution remaining on the surface of the base membrane is removed; coating the organic phase solution on the surface of a base membrane, and carrying out interfacial polymerization reaction for 1-15 minutes at the high temperature of 50-90 DEG C, so as to prepare a polyquaternary ammonium membrane on the base membrane; and washing the surface of the polyquaternary ammonium membrane with an organic solvent to remove residual reactants, and then carrying out heat treatment in a drying oven to obtain the acid-resistant polyquaternary ammonium membrane.

An underdrain filtered water collection system includes: a pair of opposing drainpipes, each drainpipe having a plurality of collection drains; and a diffuser screen. The diffuser screen can slide within an outlet in each of the collection drains. A diffuser screen for a pressure vessel containing filter media includes: a screen pipe; a solid plate coupled to a base of the screen pipe; and a winged diffuser arranged around an outer circumference of the solid plate. The winged diffuser includes a plurality of foldable wings. The screen pipe includes a mesh screen having preconfigured interstices therethrough. Feed water flows through the screen pipe where it is directed by an inner surface of the solid plate to flow in a diffused flow through the interstices of the mesh screen and the wings.

The invention discloses a preparation method of a crown ether functionalized anti-pollution nanofiltration membrane, which comprises the following steps: soaking a membrane of a commercial nanofiltration membrane in pure water, and coating the surface with a double-end epoxy compound ethanol solution; uniformly coating the surface of the membrane with an aza 12-crown-4 methanol solution; and drying the membrane in an atmosphere of 40-90 DEG C to obtain the crown ether functionalized anti-pollution nanofiltration membrane. The nano-filtration membrane is realized by chemically grafting aza 12-crown-4 on the membrane surface of a commercial nano-filtration membrane by utilizing a double-end epoxy compound; compared with a traditional nanofiltration membrane, the crown ether functionalized nanofiltration membrane provided by the invention has the advantages that the electronegativity of the surface is reduced, and the surface is similar to an aquatic plant molecular brush structure, so that the deposition of pollutants on the surface of the membrane can be effectively improved, and the anti-pollution performance of the membrane is enhanced; meanwhile, due to the complexing effect of 12-crown-4 molecules on lithium ions, the lithium ions can be effectively captured, concentration polarization of the lithium ions on the surface of the diaphragm is improved, and then the magnesium-lithium separation efficiency of the diaphragm is improved.

The invention relates to the technical field of ammonia water preparation, in particular to a raw water reverse osmosis treatment device for ammonia water preparation, which comprises a shell, the shell is formed by fixing an upper shell and a lower shell, a water inlet pipe is fixed in the middle of the top of the shell, a high-pressure water inlet component is arranged at the top of the water inlet pipe, and a concentrated water outlet pipe is fixed in the middle of the bottom of the shell. A drain valve is fixedly mounted at the bottom of the concentrated water outlet pipe; and the water pressure stabilizing assembly is arranged at the top of the inner wall of the shell. A multi-level pressure regulation and control mechanism is constructed in the reverse osmosis process, the problem of instantaneous pressure impact when the high-pressure pump is started is solved, physical damage to the membrane is avoided, a dual anti-blocking system of active rotary cleaning and back flushing is constructed, the membrane blocking probability is greatly reduced, meanwhile, the impact force of water flow is fully weakened in the back flushing stage, and the reverse osmosis efficiency is improved. It is ensured that the reverse osmosis membrane bears stable pressure all the time, and the problem of secondary damage to the reverse osmosis membrane caused by too large instantaneous pressure in the backwashing stage is avoided.

The invention relates to a composite reverse osmosis membrane acidic cleaning agent, a preparation method and a cleaning process thereof, and belongs to the technical field of environment-friendly water treatment. The cleaning agent comprises the following components in percentage by mass: 4-8% of inorganic acid, 20-40% of organic acid, 1-3% of a surfactant, 0.5-1% of a chelating agent, 0.5-1% of a compound corrosion inhibitor and the balance of deionized water. The composite corrosion inhibitor is formed by compounding 2-mercaptobenzothiazole and the like according to a specific mass ratio, the molecular weight of polyaspartic acid is 5000, and the molar ratio of Zn to Mo in the zinc-molybdate compound is 2: 1. The preparation method comprises the following four steps: firstly preparing a compound corrosion inhibitor premix, then preparing an acidic base solution, and then sequentially adding the components to finally obtain the cleaning solution. According to the cleaning process, a cleaning agent and deionized water are mixed, the membrane flux recovery rate is larger than or equal to 85% through cleaning of a specific process, the reverse osmosis membrane can be effectively cleaned, and the performance of the reverse osmosis membrane can be recovered.

The invention relates to the technical field of reverse osmosis membrane supports, in particular to a polyester non-woven fabric and a preparation method and application thereof.The preparation method comprises the steps that S1, polyester main body fibers and polyester adhesive fibers are used as raw materials to prepare high-quantitation original cloth M0 and low-quantitation original cloth H0; carrying out hot pressing pretreatment on the H0 to obtain a product H0 '; s2, overlapping and hot-pressing M0 and H0 'to obtain a composite non-woven fabric M1H1; s3, the M1H1 is impregnated with a functional solution, and the functional solution contains para-aramid nanofibers and nano calcium carbonate modified by hexadecyl trimethyl ammonium bromide; and then carrying out cold pressing on the composite non-woven fabric impregnated with the functional solution to obtain the nano-material modified composite non-woven fabric. And S4, carrying out secondary hot pressing treatment to obtain the polyester non-woven fabric. The polyester non-woven fabric can effectively avoid the problems of excessive curling, excessive permeation of a polysulfone solution and the like during curing after being coated with polysulfone, and is more beneficial to application in a reverse osmosis membrane.

The present invention discloses a high-performance reverse osmosis membrane and a method for preparing the same. The reverse osmosis membrane comprises a polyester non-woven fabric layer, a polysulfone-based membrane, and a polyamide skin layer stacked in sequence. The polysulfone-based membrane has a micron-scale prism structure on the side away from the polyester non-woven fabric layer. The preparation method comprises coating the surface of the polyester non-woven fabric layer with the polysulfone-based membrane, and forming the micron-scale prism structure on the surface of the polysulfone-based membrane by cold pressing with a roller mold during the process of converting the polysulfone-based membrane from a liquid state to a solid state. The present invention improves the flux without affecting the desalination rate of the reverse osmosis membrane or sacrificing the thickness of the skin layer, thereby resolving the trade-off between flux and desalination in the current technology. At the same time, the micron-scale prism structure can be designed into different shapes according to performance requirements, thereby achieving precise control of the flux performance of the reverse osmosis membrane.

The invention relates to the technical field of water purifiers, and provides a water purifier control method, device and equipment and a storage medium, and the method comprises the following steps: when an instruction of starting water production is received, obtaining any random number from a preset random number range; if the random number is within a preset first range, firstly filtering tap water flowing in from a main water inlet through a first reverse osmosis membrane, then enabling wastewater output by the first reverse osmosis membrane to flow into a second reverse osmosis membrane for secondary filtration, and then enabling the wastewater to flow out from a main water outlet; if the random number is within a preset second range, firstly filtering the tap water flowing in from the main water inlet through a second reverse osmosis membrane, then enabling the wastewater output by the second reverse osmosis membrane to flow into the first reverse osmosis membrane for secondary filtration, and then enabling the wastewater to flow out from the main water outlet. According to the invention, the first reverse osmosis membrane or the second reverse osmosis membrane can be prevented from being invalid in advance due to overuse, so that the service life of each osmosis membrane in the reverse osmosis filter piece is prolonged.

A subsea fluid processing system includes an electric motor that rotates a shaft on which impellers are fixedly mounted. Diffusors are static and fixed to the pump housing. The electric motor includes a rotor surrounding the shaft and a stator that is filled with a dielectric stator fluid. The stator is sealed or “canned.” The inner surface of the stator which faces the rotor is canned with a canning non-metallic material. The motor, as well as bearings for the rotating shaft are lubricated and cooled with a fluid that in some cases is taken from the process fluid and some alternative source. Alternative sources include: MEG, methanol, treated seawater and untreated seawater.

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 relates to the technical field of membrane separation, in particular to a high-flux high-salt rejection rate reverse osmosis membrane as well as a preparation method and application thereof. The preparation method comprises the following steps: sequentially contacting a porous base membrane with a water phase solution and an oil phase solution to generate an interfacial polymerization reaction to form a primary reverse osmosis membrane, and sequentially contacting the primary reverse osmosis membrane with a nitrous acid or salt solution thereof and a hydrosulfite solution to obtain the reverse osmosis membrane with high flux and high salt rejection rate, the water-phase solution contains a water-phase cosolvent, and the oil-phase solution contains an oil-phase cosolvent. According to the preparation method, cosolvents are creatively added into a water-phase solution and an oil-phase solution in an interfacial polymerization reaction process to regulate and control the microstructure of a polyamide layer, and a diazo reaction promotes further crosslinking of residual aniline groups, so that in-situ densification regulation and control of a polyamide network structure are realized; the trade-off effect of the water flux and the salt rejection rate of the traditional reverse osmosis membrane is successfully broken through.

The invention discloses a method for preparing a polyvinyl polyamide composite reverse osmosis membrane by coupling reversed-phase interfacial polymerization with lignosulfonate, which adopts a reversed-phase interfacial polymerization method and comprises the following steps: firstly adding an oil phase containing polyacyl chloride, and then adding a water phase containing amine monomers and lignosulfonate. Molecules of the lignosulfonate contain more sulfonate radicals, so that the lignosulfonate is endowed with hydrophilicity, meanwhile, a large number of active functional groups such as phenolic hydroxyl groups, alcoholic hydroxyl groups and carboxymethyl exist, and oxygen atoms, sulfur atoms and the like in the functional groups contain unbonded electron pairs and can participate in interfacial polymerization reaction to form a cross-linked structure; the trade-off effect of the flux and the rejection rate of the reverse osmosis membrane is broken, and the polyvinyl polyamide reverse osmosis membrane with high flux and high rejection rate is obtained. The raw material of the polyethylene base material is low in price, and the product can be applied to the fields of water treatment, seawater desalination, brackish water desalination and the like on a large scale.

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 invention relates to an aquaporin bionic nanofiltration membrane and a preparation method and application thereof.The aquaporin bionic nanofiltration membrane is composed of a cell sheet rich in aquaporin and a porous base membrane, and the cell sheet rich in aquaporin serves as a functional unit; through a vacuum filtration method, layer-by-layer assembly and cross-linking curing, the bonding firmness in the active layer is improved. The preparation method disclosed by the invention is simple in operation process, the embedding amount of the aquaporin in the nanofiltration membrane is increased, and the biological activity of the aquaporin is ensured. The aquaporin bionic nanofiltration membrane disclosed by the invention is high in stability and excellent in permeation selectivity, and has a wide application prospect in the field of membrane separation.

The invention relates to the technical field of water treatment, in particular to a reverse osmosis membrane and a preparation method thereof. The preparation method of the reverse osmosis membrane comprises the following steps: soaking a base membrane in a water phase solution, taking out the base membrane, drying the surface of the base membrane, coating the base membrane with an oil phase solution, carrying out interfacial polymerization reaction, curing, coating with a modifier solution, and drying to obtain the reverse osmosis membrane, the modifying agent comprises 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine-1, 3, 5-tri (4-methyl phenyl) benzene. The successfully grafted COFs can improve the water permeability of the membrane to a certain extent, and also can improve the pollution resistance, acid resistance and oxidation resistance of the membrane, so that the service life of the membrane is prolonged. According to the invention, different effects of the same type of imino COFs introduced to the reverse osmosis membrane are further compared, so that the excellence of the selected imino COFs is highlighted.

The present invention relates to the field of water treatment technology, and more particularly to a kind of reverse osmosis membrane and preparation method thereof.The preparation method of the reverse osmosis membrane includes:Basement membrane is soaked in aqueous phase solution, after taking out surface drying, oil phase solution is coated on basement membrane and carries out interfacial polymerization reaction, after solidification, coating modifier solution, after drying, obtain reverse osmosis membrane;The modifier includes 2,4,6-tris (4-aminophenyl) ‑1,3,5-triazine ‑1,3,5-tris (4-methylphenyl) benzene.The COFs successfully grafted by the present invention can improve the water permeability of membrane to a certain extent, and can also improve the anti-pollution property, acid resistance and oxidation resistance of membrane, and then improve the service life of membrane.The present invention further compares the different effects that the same type of imino COFs are introduced into reverse osmosis membrane, so as to highlight the excellence of the imino COFs selected by the present invention.

The invention relates to the technical field of water treatment, and provides a reverse osmosis membrane cleaning method, a cleaning agent composition and application. According to the method, whether cleaning is needed or not is determined by comparing initial operation parameters and current operation parameters of a system; the pollutant type is accurately judged by observing the appearance characteristics of the membrane surface and detecting related index parameters; and selecting a corresponding cleaning agent formula according to the pollutant type, and sequentially performing physical washing and chemical cleaning. The cleaning agent composition comprises a biological pollution cleaning agent, an organic pollution cleaning agent and / or an inorganic scaling cleaning agent. By establishing a scientific pollution diagnosis system and a targeted cleaning strategy, the problems of fixed cleaning scheme and low pertinence in the prior art are solved, the pressure difference recovery rate after cleaning can reach 90% or above, the desalination rate recovery rate can reach 99% or above, the cleaning efficiency is remarkably improved, the operation cost is reduced, and the service life of the membrane is prolonged.

The invention relates to the technical field of membrane separation and seawater desalination, in particular to a high-boron-removal-rate reverse osmosis membrane and a preparation method and application thereof. The polyamide reverse osmosis membrane with at least 70% nodular areas on the surface is prepared by introducing the ethylenediamine tetraacetic acid metal salt into the water phase solution as a complexing additive, and the boron removal rate of the membrane can be improved on the basis of ensuring the retention rate and flux of the membrane.

According to the efficient water treatment system based on the reverse osmosis membrane and the control method provided by the invention, gradient anti-pollution membrane arrangement and reconfigurable intelligent waterway design are creatively combined, so that a foundation is laid for high-flux and low-pollution operation from a physical structure; meanwhile, a full-closed-loop intelligent control system is constructed, and by fusing fuzzy logic, an optimization algorithm and a neural network prediction model, the system can integrate multi-dimensional information such as inlet water quality, membrane pressure difference and water yield, judge pollution risks in real time and adaptively and seamlessly switch among a high recovery mode, a segmented flushing mode and a prediction cleaning mode, so that the system is high in recovery efficiency and high in reliability. Meanwhile, parameters such as pump frequency and valves are dynamically optimized to find an optimal balance point of recovery rate and energy consumption; according to the invention, the recovery rate can be stably improved, the membrane pollution rate is greatly reduced, the chemical cleaning period and the service life of the membrane element are prolonged, and finally, the comprehensive operation and maintenance cost of the system is remarkably reduced while the water treatment efficiency and the water quality safety are improved.

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.

This invention relates to the field of water treatment technology, specifically to a reverse osmosis membrane cleaning agent composed of a non-oxidizing bactericide and an enzyme, and its application. Its main purpose is to remove biofouling from reverse osmosis membranes and restore membrane flux. This patent discloses a novel reverse osmosis membrane cleaning agent formulation. Considering the different pH requirements of the cleaning agent in actual production, different types of bioactive hydrolytic enzymes are selected to disrupt the structure of bacterial cell walls and their extracellular polymers. A reducing agent and a non-oxidizing bactericide are combined to enhance the cleaning effect of the reverse osmosis membrane. For different cleaning purposes, non-oxidizing bactericides suitable for acidic and alkaline cleaning are formulated. Sodium benzoate and benzalkonium chloride show good application prospects in the removal of reverse osmosis membrane fouling.

The invention relates to the technical field of reverse osmosis membrane maintenance, in particular to a cleaning scale inhibitor special for a reverse osmosis membrane and application of the cleaning scale inhibitor. The cleaning scale inhibitor provided by the invention comprises an agent A, an agent B and an agent C, the agent A comprises the following components in percentage by mass: 10-20% of organic phosphonic acid, 10-20% of polycarboxylic acid polymer, 5-10% of sulfamic acid, 3-8% of sodium gluconate and the balance of water; the agent B comprises 8-15% of an isothiazolinone bactericide, 5-10% of a nonionic surfactant, 3-8% of a chlorine bactericide, 2-5% of sodium dodecyl benzene sulfonate and the balance of water; and the agent C comprises 10-20% of sodium polyacrylate, 8-15% of sodium hexametaphosphate, 5-10% of citric acid, 3-8% of silicate and the balance of water. The cleaning scale inhibitor provided by the invention has an efficient cleaning effect on various pollutants, is environment-friendly, and does not cause chemical damage to a reverse osmosis membrane.

The invention discloses an inorganic atomic layer reinforced high-temperature-resistant nanofiltration membrane and a preparation method and application thereof, and belongs to the technical field of water treatment.The preparation method comprises the steps that firstly, a polymer porous basement membrane is modified through an atomic layer deposition technology, an inorganic atomic layer is introduced to the porous basement membrane, and the modified porous basement membrane is prepared; and performing interfacial polymerization reaction on a water-phase solution containing an amine monomer and a surfactant and an oil-phase solution containing a multi-acyl chloride monomer on the modified porous substrate membrane, and curing and cross-linking to prepare the inorganic atomic layer reinforced high-temperature-resistant nanofiltration membrane. According to the method, the thickness of the inorganic atomic layer can be accurately controlled, the mechanical strength and thermal stability of the porous basement membrane are improved, and the product high-temperature-resistant nanofiltration membrane has excellent high-temperature nanofiltration performance, water flux and long-term stability and is suitable for water treatment, ion screening and the like in a high-temperature environment.

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.

Disclosed herein are a membrane suitable for separation of chemical species, the membrane comprising a ceramic substrate having a first surface and a second surface, an anchoring chemical layer on the first surface of the ceramic substrate, and a covalent organic framework (COF) layer on the anchoring chemical layer, and a method of using the membrane in a process of separating a first organic compound from a second organic compound. Also disclosed herein are a method of forming a membrane suitable for separation of chemical species, and a device to manufacture a membrane suitable for separation of chemical species.

The invention provides a preparation method of a high-flux stable-selection anti-fouling nanofiltration membrane, which comprises the following steps: carrying out amination modification on a nano material by an activation method to prepare a modified nano material; piperazine, an acid absorbent and the modified nano material are added into deionized water to be mixed, and a water phase solution is prepared; the preparation method comprises the following steps: mixing trimesoyl chloride and normal hexane to prepare an organic phase solution; immersing the polyethersulfone-based membrane into the water phase solution, draining, inversely immersing into the organic phase solution, and carrying out interfacial polymerization reaction to generate a polyamide layer to obtain a composite membrane; and then carrying out post-treatment on the composite membrane to obtain the composite membrane. The membrane has high permeability, high selectivity and strong anti-pollution performance.

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.