22results about How to "High ion selectivity" patented technology

The invention belongs to the technical field of separation membrane materials, and provides a covalent organic framework membrane as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing an organic phase solution containing a polyaldehyde monomer and a water phase solution containing a polyamine monomer; dropwise adding the organic phase solution to the aqueous phase solution for reaction, and dialyzing the solution after the reaction is finished to obtain a purified aqueous dispersion of the covalent organic framework nanosheet; and dispersing the aqueous dispersion, carrying out suction filtration to a hydrophilic support, and carrying out heat treatment and curing. The invention also discloses the covalent organic framework membrane prepared according to the method and application thereof. The covalent organic framework membrane is used for removing divalent ions in a saline solution. The covalent organic framework membrane disclosed by the invention has an ordered pore structure with a specific size and high ion selectivity; due to the strong covalent bond connection characteristic, the covalent organic framework film is endowed with acid and alkali resistance and high stability; the preparation method disclosed by the invention is simple, mild in condition and wide in application range.

The invention provides application of a CoSe2-rGO catalyst in degradation of ofloxacin, and belongs to the technical field of sewage treatment. The graphene oxide (GO) with good ion selectivity, strong mechanical property and pollution resistance is used as a carrier, the carrier is combined with the transition metal selenide through a simple hydrothermal method to form a heterojunction composite material, and the prepared CoSe2 / rGO composite catalyst is used for activating PMS, has excellent catalytic activity, stability, durability and universality, and has good application prospects. And a feasible choice is provided for green elimination of antibiotic pollution in the environment.

The invention discloses a preparation method and application of an antioxidant MXene-based flowing electrode material capable of realizing efficient capacitance defluorination, and belongs to the technical field of water treatment. The preparation method comprises the following steps: sequentially carrying out nitrogen doping and cysteine modification on MXene to obtain the antioxidant MXene-based flowing electrode material capable of realizing efficient capacitance defluorination. The MXene is prepared by a Lewis acid fused salt etching method. According to the method disclosed by the invention, the electrochemical performance of the MXene electrode is effectively improved, the conductivity of the MXene electrode is enhanced, the protection of terminal groups is realized through cysteine modification, and the oxidation resistance of the MXene electrode is improved. The anti-oxidation MXene-based flowing electrode material prepared by the invention has high specific surface area, large pore volume and multiple adsorption sites, and can realize specific efficient adsorption of fluorine ions through ion intercalation and special functional groups at end positions.

The invention provides a preparation method of an HNT modified polymer composite membrane. The preparation method comprises the following steps: S1, preparing dealuminated HNT; s2, preparing modified HNT by using the dealuminated HNT; s3, preparing sulfonated polyether ether ketone; s4, performing ionization treatment on the sulfonated polyether ether ketone; and S5, preparing the HNT modified polymer composite membrane by using the modified HNT and the sulfonated polyetheretherketone or perfluorosulfonic acid membrane obtained in the step S4. The problems that an existing flow battery diaphragm is poor in comprehensive performance, high in cost and not suitable for various systems are solved.

The invention discloses a pyrenyl Schiff base fluorescent derivative, a fluorescent probe, a preparation method of the pyrenyl Schiff base fluorescent derivative and application of the pyrenyl Schiff base fluorescent probe in biological imaging, and belongs to the technical field of fluorescent probes. The pyrenyl Schiff base fluorescent probe capable of specifically detecting the zinc ions is prepared through two-step chemical reaction of Suzuki coupling reaction and aldehyde amine condensation reaction, and the pyrenyl Schiff base fluorescent probe has good recoverability and low cytotoxicity, is high in practicability and low in cost, and can be applied to detection of the zinc ions. In addition, the sensor has excellent ion selectivity to zinc ions, extremely high sensitivity, good Stokes displacement and visual sensing performance, and detection of exogenous zinc ions and endogenous zinc ions in cells and tissues is realized through biological imaging. The problems of difficult synthesis process, slow response speed, high detection cost, non-ideal biological imaging effect and the like of the conventional fluorescent derivative are solved.

The invention discloses a preparation method of a two-property proton exchange membrane with a reticular structure, which comprises the following steps: by taking a sulfonated aromatic polymer as a base material, preparing an amphoteric functionalized proton exchange membrane CS-S with the reticular structure through a cross-linking reaction of a cross-linking agent containing a multi-amino group and the sulfonated aromatic polymer; the amphoteric membranes with different crosslinking structures and crosslinking degrees are prepared by adjusting the variety and dosage of the crosslinking agent; according to the amphoteric membrane, multiple cross-linked side chains are used as base points, linear sulfonated aromatic polymer molecular chains are connected into a net-shaped structure, and the mechanical performance and the chemical stability of the proton exchange membrane are enhanced; an imino basic group on a cross-linked side chain constructs a selective proton transmission channel along the cross-linked side chain through a Donna effect and acid-base interaction between the imino basic group and a sulfonated aromatic polymer chain segment, so that the durability and the ion selective transmission performance of the CS-S two-property proton exchange membrane are improved; the process is simple to operate, low in cost and good in battery performance, is a green and energy-saving production process and is wide in application range.

The invention relates to the technical field of flow battery diaphragms, and discloses a polyamide-like covalent organic framework diaphragm for a vanadium battery and a preparation method of the polyamide-like covalent organic framework diaphragm. Comprising the following steps: preparing a porous base membrane; preparing covalent organic framework nanosheet dispersion liquid by a solvothermal oxidation method; preparing a two-phase solution of interfacial polymerization; and preparing the polyamide-like covalent organic framework diaphragm. The processability of the covalent organic framework can be improved by a solvothermal oxidation method. The polyamide-like covalent organic framework diaphragm has high porosity, and pore channels are rich in sulfonic acid groups, so that the proton conductivity of the diaphragm can be improved. In addition, the polyamide-like covalent organic framework diaphragm has intrinsic pore channels of a covalent organic framework and polyamide pore channels, the effective pore diameter is reduced through a hierarchical pore effect generated by staggered arrangement of the intrinsic pore channels and the polyamide pore channels, and the ion selectivity of the diaphragm and the coulombic efficiency of the battery are improved.

The invention discloses a polyamide composite membrane based on a positively charged support layer, a preparation method and application thereof, and belongs to the technical field of water treatment membranes. The preparation method of the polyamide composite membrane comprises: (1) using an amino monomer to perform amino modification on a porous support membrane to prepare an amino support membrane; (2) immersing the amino support membrane in a functional monomer solution to generate a Michael addition reaction or a nitrogen alkylation reaction to obtain a positively charged support membrane; (3) subjecting an aqueous phase solution containing a polyamine and an oil phase solution containing a polyacyl chloride to an interfacial polymerization reaction on the positively charged support membrane to obtain the polyamide composite membrane based on the positively charged support layer. The method of the invention has simple process and low equipment requirements. The prepared polyamide nanofiltration composite membrane has large water permeation flux, good ion selectivity and high antibiotic removal rate. The method has broad application prospects in the field of water treatment, especially in the removal of trace antibiotics in drinking water.

This invention provides a covalent organic framework hybrid matrix membrane, its in-situ growth method, and its application in ion separation. The method includes: dissolving cellulose derivatives, aldehyde monomers of covalent organic frameworks, and amine monomers of covalent organic frameworks in an organic solvent to obtain a first solution, a second solution, and a third solution; mixing acetic acid solution with the first, second, and third solutions to obtain a homogeneous casting solution; and drop-coating the homogeneous casting solution for in-situ growth. This invention constructs a CD@COF hybrid matrix membrane based on a cellulose derivative matrix and a low-loading covalent organic framework filler using an in-situ growth method. The prepared hybrid matrix membrane exhibits good interfacial compatibility between the matrix and the filler. The above-mentioned hybrid matrix membrane preparation process is simple, possesses good mechanical strength and high scalability, and demonstrates high ion flux and excellent ion selectivity for separating monovalent and divalent ions. It has broad application prospects in wastewater resource treatment, lithium extraction from salt lakes, and energy storage.

The invention belongs to the technical field of hydrogel, and mainly relates to preparation and application of hydrogel with a doughnut structure. The invention aims to solve the problem that the existing seawater desalination material based on hydrogel is insufficient in recyclability. The preparation method comprises the following steps: mixing ZrOCl2. 8H2O and fumaric acid, and performing ultrasonic dispersion on the mixture and a multi-walled carbon nanotube to obtain a pretreated precursor; carrying out hydrothermal treatment on the pretreated precursor, and modifying the pretreated precursor with acryloyl chloride to obtain modified MOF801 (at) CNT; the modified MOF801-coated CNT, polyvinyl alcohol, cassava starch and a cross-linking agent are subjected to thermosensitive cross-linking treatment, and the hydrogel with the doughnut structure is obtained. The hydrogel has high application value in the field of seawater desalination, has self-adjustability of temperature response, is high in evaporation efficiency, can be recycled, and can efficiently desalinate seawater with different temperatures and components.

The invention relates to a rechargeable aqueous ZnIS flow battery system. The system includes a cathode side including an electrode material and a first storage tank providing a catholyte, where the catholyte includes zinc iodide and soluble starch, thereby forming an electrolyte having aggregated colloidal nanoparticles; an anode side comprising the electrode material and a second storage tank providing an anolyte; and a diaphragm positioned between the cathode and the anode. And the anolyte and the catholyte flow between the cathode and the anode through a peristaltic pump. The present invention provides a system for further developing colloidal electrolyte chemistry for LPPM-based flow battery systems to achieve power cost-effective and high temperature large scale energy storage.

The invention discloses a sulfonated fluorine-containing polyimide-metal organic framework composite membrane as well as a preparation method and application thereof, and belongs to the technical field of all-vanadium redox flow battery diaphragms. The method comprises the following steps: synthesizing sulfonated fluorine-containing polyimide FSPI by using a high-temperature one-step method; preparing a metal organic framework MIL-101 (Cr) by adopting a hydrothermal method; the preparation method comprises the following steps: preparing a metal organic framework alpha-Fe2O3 / MIL-101 (Cr) by adopting a hydrothermal method; and preparing the sulfonated fluorine-containing polyimide-metal organic framework composite membrane FSPI / alpha-Fe2O3 / MIL-101 (Cr) by adopting a tape casting method. An ion transmission channel is regulated and controlled by introducing a metal organic framework alpha-Fe2O3 / MIL-101 (Cr) into sulfonated fluorine-containing polyimide. And the regulated ion transmission channel is larger than hydrated protons (lt, 0.24 nm) and smaller than hydrated vanadium ions (gt, 0.6 nm), so that the ion selectivity of the sulfonated fluorine-containing polyimide diaphragm is improved. The composite membrane prepared by the invention has high proton conductivity, good vanadium resistance and excellent ion selectivity. When the prepared composite membrane is used in the all-vanadium redox flow battery, the cycling stability of the battery is improved.

The invention provides a preparation method of a composite heterogeneous membrane, which comprises the following steps: firstly, sequentially dissolving zinc salt, 2-methylimidazole and crown ether in methanol, stirring to enable the zinc salt and the 2-methylimidazole to be subjected to coordination reaction to form a zeolite imidazole skeleton, and adsorbing the crown ether on the zeolite imidazole skeleton in situ to obtain crown ether modified zeolite imidazole skeleton particles; then, adding the graphene oxide dispersion liquid into a vacuum filtration system, and intercepting graphene oxide particles in the graphene oxide dispersion liquid by a filtration membrane in the vacuum filtration system under negative pressure to obtain a graphene oxide membrane; and adding an alcoholic solution containing the crown ether modified zeolite imidazole skeleton particles into a vacuum filtration system to intercept the crown ether modified zeolite imidazole skeleton particles on the surface of the graphene oxide membrane, and pouring phenolic resin to fix the crown ether modified zeolite imidazole skeleton particles, thereby obtaining the composite heterogeneous membrane. The invention further provides the composite heterogeneous film obtained according to the preparation method and application of the composite heterogeneous film.

The invention relates to the technical field of ion exchange membrane materials in energy storage batteries, in particular to an amphoteric polymer material containing pyridine cations and sulfonate radicals, a preparation method of the amphoteric polymer material and application of the amphoteric polymer material in an ion exchange membrane of an all-vanadium redox flow battery, and solves the problem that an existing membrane material causes cross contamination of vanadium ions or poor ion conductivity. The polymer containing pyridine cations and sulfonate radicals is a poly (aryl-3-acetylpyridine) zwitterionic polymer; the preparation method I comprises the following steps: carrying out polymerization reaction on an aromatic monomer, zwitterionic 3-acetylpyridine and a non-ionized 3-acetylpyridine monomer under the catalysis of an organic solvent I and acid to prepare a poly (aryl-3-acetylpyridine) zwitterionic polymer containing pyridine cations and sulfonate radicals; the preparation method II comprises the following steps: polymerizing an aromatic monomer and 3-acetylpyridine, and then carrying out ionization reaction in an organic solvent III by using a sulfonating reagent and taking potassium carbonate as a catalyst to prepare the poly (aryl-3-acetylpyridine) zwitterionic polymer containing pyridine cations and sulfonate radicals.

The present invention provides an anion exchange membrane that has low electrical resistance when used in electrodialysis, is produced without an increase in cost, and is excellent in selective permeability to monovalent anions, and a method for producing the same. The anion exchange membrane has a tertiary amino group and a quaternary ammonium group as functional groups, such that an intensity ratio of the tertiary amino group to the quaternary ammonium group is 1.0 or more as measured by X-ray photoelectron spectroscopy on a surface of the anion exchange membrane having the tertiary amino group and the quaternary ammonium group as the functional groups.

The invention discloses a polymer film as well as a preparation method and application thereof. The polymer film has a spongy porous structure; the pore size of the polymer film is 0.05 to 150nm; the porosity of the polymer film is 1-200%; and the thickness of the polymer film is 10-500 [mu] m. According to the membrane prepared by the invention, the cyclohexane structure with good toughness and adjustable substituent groups is combined with the spongy pore structure obtained by the steam-induced phase separation method, so that the ionic conduction membrane with good mechanical property, good ion selectivity and good ionic conductivity is obtained. When the material is applied to a flow battery, good flow battery performance is obtained through multiple regulation and control of a cyclohexane structure, an organic solvent, a volatile solvent and a poor solvent steam atmosphere.

This invention provides a MOF-On-MOF composite ion separation membrane with a cross-linked metal ion system, its preparation method, and its application. First, an anolyl porous alumina membrane plate is immersed in a solution containing metal and a cross-linking agent, shaken, and then removed. Next, a first MOF membrane layer is grown hydrothermally. Then, metal and a cross-linking agent are deposited on the surface of the first MOF membrane layer. Finally, a second MOF membrane layer is deposited in situ on the surface. This invention, by constructing a cross-linked metal ion system, provides more stable and reliable binding sites for MOF membrane growth, enhances the binding stability between MOF membranes of different sizes, and enables the separation membrane to maintain high flux and ion selectivity even during long-term operation. Furthermore, by optimizing the addition of functional groups, the energy barrier differences between different metal ions across the membrane are strengthened, enhancing the selectivity for monovalent and polyvalent ions. The preparation method is simple and easily industrialized.

The invention discloses a polybenzimidazole / polyionic liquid / heteropolyacid imidazole composite ion membrane with high ion selectivity, a preparation method and application thereof, and belongs to the technical field of ion membranes. The polyionic liquid used in the invention is a type of ionic liquid polymer having anionic and cationic groups on a repeating unit, which has the excellent properties of both ionic liquids and polymers. The ion membrane obtained by blending with polybenzimidazole has high conductivity, good mechanical strength, and excellent chemical stability. At the same time, in order to further improve the conductivity of the ion membrane, an imidazole salt of an oxygen-containing polyacid (heteropolyacid imidazole salt) is added to form a composite ion membrane. In addition, the preparation method of the invention is simple in process, and the composite ion membrane obtained has high ion selectivity and stability, high mechanical strength, and still maintains high proton conductivity at high temperatures.

The present application provides an integrated electrode frame and preparation method and use thereof. The integrated electrode frame includes a positive electrode frame, a negative electrode frame, and a membrane. Each of the positive electrode frame and the negative electrode frame is a flat plate with a central through-hole. The membrane is placed between the positive electrode frame and the negative electrode frame, and the membrane is located at the through-hole and hermetically connected to a peripheral edge of the through-hole. A peripheral edge of the positive electrode frame is hermetically connected to a peripheral edge of the negative electrode frame. A material composition of a connecting part of the positive electrode frame and the negative electrode frame contains at least one material which is the same as that of the positive electrode frame or the negative electrode frame. In the present application, the structures and materials of the electrode frames and the membrane are optimized to achieve a direct hermetical connection between the membrane and the electrode frames and improve the sealing reliability and volumetric energy density of an all-vanadium flow battery.

The invention discloses a method for extracting and separating indium, and relates to the technical field of hydrometallurgy. The method comprises the following steps: mixing an extracted organic phase with an indium-containing sulfate solution, and extracting to obtain an indium-loaded organic phase; carrying out reverse extraction on the indium-loaded organic phase by adopting a sulfuric acid solution to obtain an indium-containing reverse extraction solution; carrying out acid separation and replacement to obtain indium; the extraction organic phase comprises an amine extraction agent, an acidic phosphate extraction agent and a diluent. According to the method, the extraction capacity of indium is guaranteed, meanwhile, the extraction capacity of iron ions is reduced, reverse extraction of indium and iron in the loaded organic phase is easier, chlorine-containing waste water and chlorine-containing waste residues are avoided, meanwhile, organic phase poisoning caused by difficulty in reverse extraction of iron through hydrochloric acid is avoided, and the method is suitable for industrial production. Water washing liquid, an organic phase and an acid solution generated in the extraction and separation process can be recycled, and waste water and waste residues are not generated.

The invention discloses synthesis of a sulfonated benzoxazine material (SBA) suitable for an all-vanadium redox flow battery and thermal crosslinking application of the SBA and sulfonated polyether-ether-ketone (SPEEK). According to the sulfonated benzoxazine material, a hydrophilic group sulfonic acid group is connected to a benzene ring and an N and O six-membered oxazine ring, so that the proton conductivity is enhanced while the characteristics of low curing shrinkage rate, high modulus, high strength, good heat resistance, low water absorption rate and the like of the benzoxazine material are retained. The covalent cross-linked membrane with a net-shaped structure is prepared by mixing the covalent cross-linked membrane with SPEEK with high proton conductivity and then carrying out thermal crosslinking by adopting thermal curing, so that the covalent cross-linked membrane with the net-shaped structure is prepared. On one hand, hydrophilic sulfonic acid groups carried by sulfonated polyetheretherketone and sulfonated benzoxazine form a hydrophilic structural domain, so that the proton conductivity is enhanced; on the other hand, a net structure formed by thermal crosslinking has excellent ion selectivity, the vanadium resistance is enhanced, the mechanical property and the dimensional stability are improved, and the free volume of a sulfonated polyether ether ketone matrix is limited by a crosslinking structure, so that the water absorption rate of the membrane is also greatly reduced.

The present invention discloses a method for preparing a doped and modified single crystal manganese-based lithium ion sieve and its application in extracting lithium from salt lakes. 2‑x M x O4, 0≤x≤0.1, M includes at least one of Al, Ni, Cr, and Cu; the doped and modified single crystal manganese-based lithium ion sieve is a spinel crystal. In the doped and modified single crystal manganese-based lithium ion sieve of the present invention, cation doping reduces the crystal lattice on the one hand, and cation doping replaces part of the manganese element on the other hand, reducing the proportion of manganese element, reducing the manganese dissolution loss caused by the disproportionation reaction, and alleviating the Jahn-Teller effect of the crystal.