14822results about "Semi-permeable membranes" patented technology

The invention relates to the field of wastewater treatment, and provides an industrial wastewater membrane process intelligent optimization method and system based on multi-dimensional data modeling. The method comprises the following steps: acquiring wastewater quality parameters of a target scene and a production line equipment state in real time through a multi-dimensional sensor network, and constructing a digital twinborn model of a wastewater treatment system in the target scene; the membrane surface pollution type of each node in the wastewater treatment system is identified through a digital twin model, and the inner membrane pollution evolution condition in the future preset duration is predicted; a multi-strategy evolutionary reinforcement learning algorithm is adopted, the wastewater quality parameters, the production line equipment state and the membrane pollution prediction result are combined, multi-target dynamic optimization is conducted on a wastewater treatment system through a multi-agent collaborative decision-making algorithm, an optimization strategy is generated based on the multi-target dynamic optimization result, and membrane process operation parameters and production control parameters are dynamically adjusted. According to the method, real-time intelligent adjustment of membrane process operation can be realized, the stability of membrane process operation is guaranteed, and the treatment efficiency of membrane process operation is improved.

Disclosed herein are methods and systems for producing a liquefied methane product from a methane- and carbon dioxide-containing feed stream, in which a plurality of membrane stages comprising gas separation membranes that are more permeable to carbon dioxide than methane are used to remove carbon dioxide from the feed and form a retentate stream that is enriched in methane, said retentate stream being then cooled and liquefied to provide the liquefied methane product. In particular, the disclosed methods and systems may be used for producing liquefied biomethane from a biogas feed.

Methods, systems and devices for removing iodide from an aqueous solution including submerging an iodophilic electrode in an aqueous solution containing iodide, applying a current to the electrode, and electrochemically oxidizing the iodide to iodine within the electrode. The electrode may include an iodophilic material and an electrically conductive material. It may also include a binder. The iodophilic material may be a starch, chitosan, carboxycellulose, cationic polymer, or an anion exchange membrane material, for example. After oxidizing the iodide to iodine within the electrode, the electrode may be submerged in a second solution and a current may be applied to reduce the iodine and release it from the electrode in the form of iodide into the second solution.

An ML-assisted framework is disclosed that can guide the design of fit-for-purpose separation membranes for resource recovery and clean water production from wastewaters. Approaches and methodologies for executing the work include the integrated components: 1) ML-assisted new polymer screening; 2) development of an interpretable ML model for membrane properties prediction; 3) mechanistic constitutive model; 4) development of a statistical ML model with a combination of proper regularization for membrane performance prediction; 5) separation membrane fabrication and evaluation.

The present disclosure relates to a dehumidifier.The dehumidifier according to an embodiment may include a first part in which a fan, a heat exchanger, and a dehumidification module are installed. The first part may define an upper space of the dehumidifier.The dehumidifier may include a second part in which a vacuum pump and at least one tank are installed. The second part may define a lower space of the dehumidifier.The dehumidifier may further include a first partition wall that divides the upper space of the first part and the lower space of the second part into each other.

The invention relates to catalytically coated anion exchange membranes and their production. The catalytically active coated anion exchange membranes are used in electrochemical cells, in particular for water electrolysis. The object of the invention was to provide a process for producing an electrocatalytically active coated anion exchange membrane whose coating is porous and thus the electrocatalytically active centers located in the coating are easily accessible to the reactants. A basic idea of the process according to the invention is to incorporate particulate inorganic material into the catalyst coating as a placeholder, to solidify the coating, and then to leach the inorganic material out of the coating. The leaching converts the inorganic material into a water-soluble product that can be easily washed out of the coating.What remains are voids (pores) where the particulate inorganic material was previously located within the coating. The inorganic material therefore assumes the function of a structure-imparting agent within the coating composition, which is lost during the catalytically active coating process.

The invention provides a flexible palladium film hydrogen sensor and a preparation method thereof, the flexible palladium film hydrogen sensor is sequentially provided with a flexible substrate, a hydrogen sensitive sensing layer and a contact connection layer from bottom to top, and the contact connection layer is connected with a resistance measurement unit; and the hydrogen-sensitive sensing layer is a palladium or palladium alloy film with a conical micro-nano structure. The palladium or palladium alloy thin film with the conical micro-nano structure provides a hydrogen sensor conical surface micro-nano structure with a high specific surface area for the flexible palladium thin film hydrogen sensor, and the process that hydrogen is adsorbed, dissolved and diffused into the palladium or palladium alloy thin film is accelerated, so that the response speed of the sensor is increased; according to the hydrogen sensor, the flexible substrate is adopted, so that the hydrogen sensor can be conveniently arranged in various narrow spaces, and the applicability of the hydrogen sensor in various scenes is improved.

The invention discloses a p-type or n-type COF film, the film thickness is 50 nm to 5 m, the aperture is 0.7 nm to 4 nm, and the film has a regular pore channel structure and light response performance. According to the invention, proper monomers are selected, and liquid-solid interface polymerization reaction is carried out, so that COF membranes grow along the tube wall, and p-type and n-type COF membranes are respectively prepared. The growth direction of the film is inconsistent with the transmission direction of the monomer and the catalyst, and the process can effectively promote the dissolution growth and self-repair of the COF film, so that the crystallinity and stacking orientation of the film are improved, and the structural characteristics of the COF film are optimized. The obtained COF film has a remarkable advantage of light-driven ion pump performance. The obtained COF membrane is used for preparing a desalting device.

The invention discloses a nanofiltration membrane for extracting lithium from salt lake brine with a high magnesium-lithium ratio and a preparation method of the nanofiltration membrane, and belongs to the technical field of nanofiltration composite membranes. The preparation method of the nanofiltration membrane comprises the following steps: first-time interfacial polymerization treatment, second-time interfacial polymerization treatment and post-treatment. The nanofiltration membrane with a double-layer lithium ion permeation channel is constructed through coupling of secondary interfacial polymerization and a B15C5 modification process, and stable permeation performance of the membrane is guaranteed while high magnesium ion rejection rate and high magnesium-lithium separation factor are realized through synergistic modification of crown ether and secondary interfacial polymerization. The nanofiltration membrane disclosed by the invention shows excellent performance in a real salt lake brine test, and in practical application, the membrane can effectively treat a complex brine system with a high magnesium-lithium ratio; and in a 24-hour continuous test, long-term stability is also shown, and an efficient, stable and feasible solution is provided for lithium extraction of the salt lake brine with the high magnesium-lithium ratio.

The invention provides a chemical sewage advanced treatment system and method based on multistage membrane separation, and relates to the technical field of chemical sewage treatment.The method comprises the steps that pollution load data under preset membrane flux is collected, and the cascade reflux amount in the current membrane separation process is determined through the pollution load data and a real-time pressure index during membrane separation filtration; according to the separation interference deviation, the steady-state filtering period of the membrane separation filtering grade in the constant flux change is predicted, the steady-state filtering period is synchronously screened, and the full-flow separation limit of the multistage membrane separation unit in different pollution loads is obtained; and generating a separation regulation and control index when the equivalent flux generates peak offset according to the cascade reflux quantity and the full-flow separation limit, and performing starting point triggering on the treatment flow of the multistage membrane separation sewage and dirt. Under the dynamic working condition of operation of the multistage membrane separation system, balance adjustment can be carried out on the advanced treatment process trigger of the chemical sewage, so that the standard-reaching rate of membrane separation chemical sewage advanced treatment is increased.

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 invention discloses an anti-fouling piezoelectric ceramic membrane which comprises a support body, a coil and a piezoelectric ceramic separation layer, the support body is made of porous ceramic with a through hole in the middle; the coil is a closed loop composed of a lead coil and a crystal oscillator; the piezoelectric separation layer is coated on the inner wall of the through hole of the support body; and the coil is arranged between the support body and the piezoelectric ceramic separation layer. When a medium containing electrolyte passes through a membrane hole, the coil generates induction direct current, the direct current is converted into positive wave pulse current through the oscillator, the wound and overlapped piezoelectric ceramic membrane separation layer is excited, ultrasonic vibration is generated, and therefore the membrane dirt blocking condition is reduced, the use efficiency of the ceramic membrane is improved, and the maintenance and use cost is reduced.

The invention discloses an intelligent detection and dynamic early warning system based on machine learning and multi-source data fusion, which relates to the technical field of membrane separation process monitoring and consists of a data acquisition and preprocessing part, a physical model and data driving model part, a dynamic weight fusion and self-adaptive mechanism part and a man-machine interaction and alarm part. According to the system, parameters such as membrane flux, transmembrane pressure difference, solution concentration, temperature, water inlet flow and operation pressure are collected, an improved XGBoost machine learning model is combined, and a comprehensive pollution index is constructed to quantify the membrane pollution degree; the model realizes double analysis of a pollution mechanism and a data rule through feature engineering. The system supports full-closed-loop management from minute-level early warning to hour-level cleaning decision making, the threshold value is dynamically adjusted through Bayesian optimization, the generalization and anti-interference capacity of the system are remarkably improved, and the system is suitable for intelligent operation and maintenance of membrane separation processes such as reverse osmosis and ultrafiltration.

A process and apparatus for lithium ion extraction. The process includes passing a lithium-containing brine through a lithium-adsorbent, then passing a desorption media through the lithium-adsorbent at a temperature above 40℃ to produce a lithium-enriched eluent. The lithium concentration of the eluent is further increased by passing it through a nanofiltration membrane and a reverse osmosis membrane. Preferably, the eluent is passed through these membranes more than once at a temperature above 40℃. The process is energy-efficient, because it is conducted entirely at temperatures above 40℃. Accordingly, there is no need to decrease the temperature of the lithium-enriched eluent before passing it through the nanofiltration membrane and the reverse osmosis membrane. Moreover, there is no need to increase the temperature of the nanofiltration reverse osmosis permeate before passing it through the lithium-adsorbent as a desorption media, nor is there a need to increase the temperature of the enriched lithium stream before lithium precipitation.

The invention relates to the technical field of membrane control, and discloses a membrane control method and system based on multi-parameter intelligent perception, and the method comprises the steps: obtaining multi-parameter operation data of a membrane separation system, and calculating a transmembrane pressure difference change value, an inlet and outlet water quality change rate and membrane operation load duration according to the operation data; based on the transmembrane pressure difference change value, the inlet and outlet water quality change rate and the membrane operation load duration, a pollution trend early warning model based on an improved long and short term memory network is constructed and analyzed, and a first prediction result is obtained; and performing dynamic pollution risk score calculation based on the first prediction result to obtain a pollution risk comprehensive assessment value. Linkage analysis of the pollution development trend and the system risk level is achieved, the potential pollution risk level can be recognized in advance, cleaning intervention suggestions or alarm strategies are output in a graded mode, and the initiative and timeliness of cleaning decision making are effectively improved.

The preparation method comprises the following steps: obtaining a ZnO nano-particle seed crystal layer by a dip-coating-calcining method, and growing the ZnO nano-particle seed crystal layer on a porous ceramic membrane; inducing growth of ZnO nano-clusters on the surface of the ceramic membrane on which the ZnO nano-particles grow and in pore channels of the ceramic membrane through a hydrothermal reaction; and finally, soaking the ceramic membrane on which the ZnO nano-cluster grows in an n-octyltriethoxysilane-absolute ethyl alcohol solution, and carrying out silane chemical grafting treatment. A firm micro-nano composite multilevel structure is obtained on the surface and in pore channels of the ceramic membrane after modification through the method, meanwhile, the surface free energy of the surface and pore channels of the ceramic membrane is reduced through n-octyltriethoxysilane, the surface and the pore channels of the ceramic membrane have super-hydrophobic performance, and the preparation method is simple in preparation process, short in period and suitable for industrial production. And the universality is high.

The invention discloses a high-performance composite solvent-resistant nanofiltration membrane with a rigid twisted non-planar structure polyamide layer and a preparation method of the high-performance composite solvent-resistant nanofiltration membrane. The preparation method comprises the steps of preparation of the rigid twisted non-planar structure polyamide layer and surface modification. A water phase solution containing adamantane diamine and m-phenylenediamine and an organic phase solution containing 1, 3, 5-trimesoyl chloride and acetone are subjected to interfacial polymerization reaction to prepare a polyamide layer with a rigid twisted non-planar structure, and then a polyphenol modifier is used for carrying out hydrophilic modification on the polyamide layer, so that the rigid twisted non-planar structure is obtained. The pure water permeability and retention rate of the solvent-resistant nanofiltration membrane are obviously improved; due to the introduction of adamantane diamine, the interfacial polymerization process and the formation of a polyamide layer are remarkably regulated and controlled, and the separation performance of the solvent-resistant membrane is greatly improved on the premise that the interception performance of the membrane is hardly reduced; the preparation process is simple, and the prepared membrane is excellent in performance and has a good application prospect in the aspect of organic solvent separation.

The invention relates to the technical field of membrane separation, and discloses a preparation process of a molecular screening nano filter membrane and a plastic particle filter thereof.The preparation process comprises the steps that S1, a polymer-based material and an inorganic composite material are selected, the polymer-based material comprises polyethersulfone, polyvinylidene fluoride or polyimide, and the inorganic composite material is added into the polymer-based material; the inorganic composite material comprises a metal organic framework or graphene oxide; s2, an additive is prepared, and the additive comprises polyvinylpyrrolidone, nano titanium dioxide or silver nanoparticles; s3, the polymer-based material and the inorganic composite material are dissolved in a proper solvent, a polymer solution is obtained, and the solvent comprises NMP, DMF or THF; and S4, coating the polymer solution on the surface of the support body by adopting a phase inversion method. By optimizing the membrane layer structure, enhancing the mechanical strength, improving the anti-pollution capacity and improving the post-treatment process, the stability and durability of the nanofiltration membrane are improved, and the high-efficiency long-term separation requirement is met.

The invention belongs to the technical field of polymeric membrane materials, and particularly discloses a polycarbonate / cellulose acetate blended ultrafiltration membrane as well as a preparation method and application thereof. The polycarbonate / cellulose acetate blended ultrafiltration membrane is prepared by blending cellulose acetate and polycarbonate, and has the advantages of simple preparation method, low cost, low energy consumption, good stability and the like; meanwhile, the double advantages of polycarbonate and cellulose acetate are combined, remarkable hydrophilic enhancement and efficient permeability are shown, the purpose of separation and purification can be achieved, and the composite material has huge potential application prospects in the fields of seawater desalination, sewage treatment, rainwater collection and treatment and the like.

The invention discloses an alumina-based catalytic ceramic membrane loaded with high-content ferric oxide as well as a preparation method and application of the alumina-based catalytic ceramic membrane, and belongs to the technical field of inorganic functional ceramic microfiltration membranes and preparation of the inorganic functional ceramic microfiltration membranes. The invention solves the problems that the catalytic action of the existing catalytic ceramic membrane is limited by low catalyst loading capacity, the preparation process is complicated, the cost is high and the like. When the aluminum oxide-based ceramic membrane is prepared, silicon dioxide is added to generate a liquid phase in the sintering process to promote sintering, the catalyst alpha-Fe2O3 is added into the ceramic powder before sintering, the ceramic membrane with the catalytic function is prepared in a one-step forming and co-sintering mode, the preparation process is simplified, and meanwhile the preparation cost is reduced. The content of alpha-Fe2O3 on the surface and in the ceramic membrane is increased, and Fe < 3 + > is utilized to activate crystal lattices to promote sintering. Along with the increase of the addition amount of alpha-Fe2O3, small pores are discharged in the sintering process, pore walls are shrunk, macropores are generated, the pore diameter of the ceramic membrane is gradually increased, and the permeation flux of the ceramic membrane is improved.

The invention relates to a synthesis method and application of a poly (ether) sulfuryl block copolymer based on chain exchange reaction, and belongs to the technical field of high polymer materials, the synthesis method comprises the following preparation steps: S1, taking an organic solvent, adding a poly (ether) sulfuryl material into the organic solvent, heating and stirring until the poly (ether) sulfuryl material is completely dissolved to obtain a mixed system; and S2, adding an amino-containing hydrophilic polymer material with reaction activity into the mixed system prepared in the step S1, and removing the solvent after reaction to obtain the poly (ether) sulfuryl block copolymer. The preparation process is easy to operate, the production period is short, the obtained material is stable in performance, and industrial production is easy.

The invention discloses a method for preparing a polymer anti-pollution membrane, which is characterized in that a'fluorine-containing polymer / styrene-maleic anhydride 'porous membrane is prepared by taking a styrene-maleic anhydride copolymer and a fluorine-containing polymer as base materials and adopting a thermally induced phase separation technology. And loading chitosan on the surface of the porous membrane by utilizing a chemical reaction between anhydride on the surface of the membrane and a small part of amino groups in a chitosan chain. The chitosan molecular chain with pH responsiveness not only improves the hydrophilicity of the membrane and slows down the deposition of inorganic scales on the surface of the membrane, but also has the conformation subjected to'curl-stretch 'reversible transformation (similar to'curl-stretch' motion of earthworms in soil so as to soften the soil) in the'acid washing-alkali washing 'cleaning process of the membrane; hardened inorganic scale deposited on the surface of the membrane becomes loose, the binding force between the inorganic scale and the surface of the membrane becomes weak, and the inorganic scale can be effectively removed through surface water cleaning in the follow-up process. The prepared cleaning agent has the advantages of being high in pollution resistance, good in inorganic dirt removal effect after cleaning and the like.

The invention discloses a high-salt-rejection and pollution-resistant polyamide reverse osmosis membrane, which is characterized in that an aromatic cationic surfactant containing two benzene ring structures is adopted to regulate and control the interfacial polymerization reaction of a polyamine monomer and a polyacyl chloride monomer, and a high-salt-rejection and pollution-resistant polyamide functional layer is generated on a porous ultrafiltration base membrane. The effective specific surface area of the polyamide functional layer of the reverse osmosis membrane is gt; 1.2, the surface potential gt when the pH is equal to 7; -20 mV; the molecular weight cut-off of the polyamide reverse osmosis membrane is 1t; the molecular weight is 100Da, and the retention rate for 2000ppm of NaCl is gt; the anti-fouling coating has the advantages of good hydrophilicity and excellent anti-fouling performance. The preparation process of the polyamide reverse osmosis membrane is simple and efficient, and has industrial application potential. The polyamide reverse osmosis membrane can be used for purification and treatment of different types of water, and has important application value.

The invention belongs to the technical field of micro-nano processing, and particularly relates to a preparation method and application of a metal micro-nano tube array. Comprising the following steps: preparing a metal layer on the surface of a substrate; coining glue is sprayed on the surface of the metal layer, then coining is conducted through a template, and a micro glue column array is formed after curing; a plasma etching process is adopted, the micro glue column array is used as a mask, the metal layer exposed out of the gaps in the bottom of the micro glue column array is etched, and a structure with the micro glue columns wrapped by metal is formed; and removing the rubber columns in the structure of the metal-coated micro rubber columns to obtain the metal micro-nano tube array. According to the invention, a residual-layer-free imprinting technology is adopted, the problem of glue layer residue in traditional imprinting is avoided, and the etching uniformity is improved. A plasma dynamic balance process is adopted, the side wall redeposition effect of etching by-products is utilized, and the metal micro-nano tubes are formed in a self-assembly mode. The prepared metal micro-nano tube array has high aspect ratio compatibility, and the nano tube array with the aspect ratio as high as 10: 1 can be realized.

The invention discloses a low-cost and environment-friendly process for producing 1, 4-bis (4-fluorobenzoyl) benzene, and belongs to the technical field of Friedel-Craft reaction, fluorobenzene and paraphthaloyl chloride react to generate 1, 4-bis (4-fluorobenzoyl) benzene, after reaction quenching, filtering is performed to obtain a crude product 1, 4-bis (4-fluorobenzoyl) benzene and filtrate, and the 1, 4-bis (4-fluorobenzoyl) benzene is purified in a sublimation crystallization mode; standing and layering the filtrate in an inclined plate layering device, respectively treating an oil layer and a water layer, dehydrating a fluorobenzene layer in a dehydrating tower, and returning fluorobenzene; the water phase is firstly subjected to organic matter removal treatment, the obtained organic matter enters a fluorobenzene recovery device to be sleeved back, and the obtained water phase is a byproduct of crystallized aluminum chloride in an evaporative crystallization device. According to the process, the 1, 4-bis (4-fluorobenzoyl) benzene is produced in a sublimation crystallization mode instead of a solution crystallization mode, no waste solvent is generated, the waste solvent does not need to be recycled, the cost is low, organic matter removal and evaporative crystallization treatment is carried out on wastewater, organic matter recycling is carried out, crystalline aluminum chloride is produced as a byproduct, and wastewater and waste salt are not discharged.

The invention discloses a preparation method of a photocatalytic nanofiltration membrane based on IL-GQDs. The method comprises the following steps: pretreating bagasse, and applying the pretreated bagasse and imidazole ionic liquid (IL) to preparation of ionic liquid functionalized graphene quantum dots (IL-GQDs); the IL-GQDs are uniformly distributed on the surface of the base membrane by utilizing a vacuum-assisted low-temperature interfacial polymerization technology to form an ultrathin photocatalytic active layer; and finally, curing and cleaning to obtain the photocatalytic nanofiltration membrane based on the IL-GQDs. According to the prepared IL-GQDs, the membrane surface is endowed with high specific surface area and excellent photocatalytic activity, and meanwhile, an additional water transmission channel can be established under the condition that the pore diameter of the membrane is not changed, so that the problem of trade-off of a traditional membrane is solved. In addition, through combination of low-temperature and vacuum-assisted interfacial polymerization technologies, the membrane structure is more uniform and compact, defects on the surface of the membrane are reduced, and the stability and the anti-pollution capacity of the membrane are improved. The membrane disclosed by the invention shows relatively high water flux, salt recovery rate and long-term stability in water treatment application.

The utility model discloses a reverse osmosis membrane testing device which comprises a testing table, a placing groove, a valve, a water storage tank, a water suction pump and a water conveying pipe hydraulic oil cylinder, the placing groove is formed in the testing table, a first elastic piece is arranged in the placing groove, a sewage draining opening is formed in the bottom of the placing groove, a water purifying pipe is arranged in the sewage draining opening, and a water outlet is formed in the water purifying pipe. A sealing gasket is arranged at the top of the water purification pipe, a water purification bin is connected to the bottom of the sealing gasket, a sewage bin is arranged at the bottom of the sewage outlet, and a partition plate is arranged in the sewage bin and the water purification bin. A clamping and fixing joint composed of a placing groove, an extrusion cover, a fixing table and a hydraulic oil cylinder is arranged on the test table, so that a reverse osmosis membrane placed in the placing groove can be quickly clamped and fixed through the extrusion cover by virtue of the movement of the hydraulic oil cylinder, and the extrusion cover is connected to the fixing table through a threaded rod, so that different heights at different positions are avoided; fine adjustment can be carried out through rotation of the threaded rod, and a first spring piece is arranged in the containing groove.

The invention belongs to the technical field of membrane separation, and aims to provide a preparation method and application of a covalent organic framework bipolar membrane. The method comprises the following steps: combining at least one amine, hydrazide or aldehyde monomer containing ionic groups with a monomer without ionic groups, and respectively synthesizing covalent organic framework COF nanosheets with positive charges and negative charges through a one-pot method under the condition of coexistence of an acid catalyst and an organic solvent; sequentially depositing COF nanosheets with positive and negative charges on the surface of the porous carrier by a hot solvent evaporation method; by constructing two COF separation layers with regular pore channels and opposite electrical properties, the covalent organic framework bipolar membrane with charge asymmetry is finally obtained. The product provided by the invention has high selectivity, can realize efficient separation of protons and metal cations, and significantly improves the extraction and recovery purity of hydrochloric acid; through charge repulsion and pore size screening mechanisms, separation of different anions can be further realized, and selective recovery of acid molecules is enhanced.

The invention belongs to the technical field of preparation of diaphragm materials, and particularly relates to a preparation method of a polymer porous membrane, the polymer porous membrane and application. The method comprises the following steps: (1) obtaining a film containing a polymer and a plasticizer; (2) extracting the plasticizer in the thin film by adopting an extracting solution to obtain a wet film; and (3) the wet film is dried, and in the drying process, the size shrinkage rate of the wet film in the TD direction ranges from 5% to 20%. The polymer porous membrane prepared by the method has high-temperature dimensional stability and good air permeability and thickness uniformity.

The invention relates to a preparation method of a nanofiltration membrane containing a covalent organic framework (COF) interlayer. The nanofiltration membrane (NF) comprises a base membrane, an interlayer and a separation surface layer. The interlayer is formed by in-situ growth of polyphenol and diamine under the action of an oxidizing agent, and the separation surface layer is formed by an aqueous-phase active monomer and multi-element acyl chloride through an interfacial polymerization reaction. According to the invention, an imino covalent organic framework (TpPa-COF) film interlayer is introduced, and a surface polyamide layer is prepared through interfacial polymerization, so that the hydrophilicity of the film and the ability of removing divalent cations are improved. The invention aims to solve the problem of balance between low flux and high separation effect of an NF membrane in separation of monovalent / divalent cations, maintain ideal water flux while ensuring high separation effect, and solve the problem that a traditional NF membrane separation layer has defects. The two-dimensional TpPa-COF material can effectively control the pore size distribution and hydrophilicity of the surface of the substrate and improve the separation performance of the composite membrane. The preparation method is simple, and the obtained nanofiltration membrane has a wide application prospect.