1350 results about "Iron salts" patented technology

The invention discloses a lithium manganese iron phosphate positive electrode material with a core-shell structure, which is prepared by the following steps: mixing a manganese source, an iron source, a phosphorus source, lithium carbonate and a carbon source, grinding and drying to prepare a pre-sintered material; then carrying out gas crushing on the pre-sintered material to obtain a pre-gas crushed material, and carrying out heat preservation at the temperature of 200-600 DEG C; putting the pre-gas crushed material subjected to heat preservation into an iron salt solution for quenching reaction to obtain iron compound coated lithium manganese iron phosphate; and finally, mixing the lithium iron manganese phosphate coated with the iron compound, a lithium source, a phosphorus source and a carbon source, grinding, drying, and carrying out secondary calcination to obtain the lithium iron manganese phosphate material with the core-shell structure. During preparation of the lithium manganese iron phosphate positive electrode material, a lithium manganese iron phosphate pre-sintered body and an iron salt solution are subjected to a quenching reaction to form an iron compound coated lithium manganese iron phosphate pre-sintered body, and then the iron compound coated lithium manganese iron phosphate pre-sintered body and other raw materials of lithium iron phosphate are subjected to a secondary calcination reaction to generate the composite positive electrode material with a core-shell structure. A coating structure is formed, the reaction between manganese and electrolyte is reduced, the dissolution of manganese is inhibited, the Gingtaler effect of manganese is relieved, and the stability of the material is improved; and the material has the advantages of high energy density, high power density, excellent cycle performance and strong core-shell interface bonding force.

The invention provides an iron-based phosphate positive electrode material as well as a preparation method and application thereof. The preparation method of the positive electrode material comprises the following steps: reacting a mixed material containing metallic iron and a phosphorus source at normal temperature to 100 DEG C to form a solid-liquid mixture containing a phosphate iron salt compound; mixing the solid-liquid mixture with an acidity regulator, a carbon source and a sodium source, and sanding to obtain slurry; performing drying treatment on the slurry to obtain a precursor material; and sintering the precursor material under a protective atmosphere condition to obtain the iron-based phosphate positive electrode material. According to the method provided by the invention, the metal iron and the phosphorus source do not need to be mixed and completely dissolved to form a solution in the reaction process, and anhydrous iron phosphate does not need to be formed firstly, so that the method for preparing the iron-based phosphate positive electrode material is short in process and relatively low in requirements on reaction conditions, and is applicable to industrial production and large-scale production.

The invention relates to the technical field of adsorbents, and particularly discloses an aluminum oxide type adsorbent and a preparation method thereof.The preparation method comprises the following steps that lanthanum salt, cerium salt and a polyethylene glycol aqueous solution are mixed to be uniform, then the mixture is mixed with gamma-Al2O3 to be uniform, pH is adjusted, standing is conducted, solid-liquid separation is conducted, drying and roasting are conducted, and a double-doped carrier is obtained; dispersing the double-doped carrier in a mixed solution containing 2-methylimidazole, ferric salt and zinc salt, adjusting the pH value, carrying out heating reaction, solid-liquid separation and drying in an inert atmosphere, grinding to obtain powder, and carrying out molding treatment on the powder to obtain a composite carrier; uniformly mixing the Ag modified molecular sieve with silica sol, coating the surface of the composite carrier with the mixture, and drying to obtain an adsorbent precursor; dipping an adsorbent precursor in the dispersion liquid, and after dipping, solid-liquid separation and drying, reactivating to obtain the aluminum oxide type adsorbent; the prepared adsorbent can synergistically and efficiently remove multiple impurities and is excellent in corrosion resistance.

The invention discloses injectable hydrogel with redox activity and electroactivity as well as a preparation method and application of the injectable hydrogel, and belongs to the technical field of medical materials. The preparation method comprises the following steps: reacting methacrylic anhydride and polysaccharide molecules in a solvent to prepare a double-bond functional polymer; the preparation method comprises the following steps: firstly, pre-polymerizing dopamine in a solvent, and then adding MOF (Metal Organic Framework) to carry out polymerization reaction, so as to prepare dopamine modified MOF; reacting the dopamine modified MOF, EDOT and ferric salt in a solvent, and collecting the precipitate to prepare a nano filler; the preparation method comprises the following steps: jointly dispersing the double-bond functional polymer, active polypeptide, a photoinitiator and nano filler into a solvent, and carrying out photocuring cross-linking. The preparation condition is mild, gel forming is rapid, the method is simple, the prepared hydrogel has injectable performance and conductive performance, catalytic activity of natural enzyme can be simulated, active oxygen removal can be achieved in the early stage of myocardial ischemia, electrical conduction of infarction parts can be enhanced, and effective recovery of cardiac functions can be achieved.

The invention relates to a preparation method of a catalyst for synthesizing 2, 6-dimethylphenol, which comprises the following steps: mixing ferric salt, aluminum salt, magnesium salt, an acidic material and water to obtain a solution A; mixing sodium silicate, a template agent and water to obtain a solution B; mixing the solution A and the solution B, aging, crystallizing, filtering, drying and calcining to obtain a catalyst precursor I; mixing with an alkaline solution, and filtering to obtain a catalyst precursor II; then mixing with an acidic solution, filtering to obtain a solid, and then washing and calcining to obtain a catalyst; the preparation method of the 2, 6-dimethylphenol comprises the following step of preparing the 2, 6-dimethylphenol by taking methanol, phenol, water and benzoic acid as raw materials in the presence of the catalyst. The catalyst provided by the invention has good catalytic activity, reduces the problem of carbon deposition, and has good selectivity and high phenol conversion rate when being used for preparing 2, 6-dimethylphenol.

The present invention relates to a new method for preparing a ferromanganese oxalate precursor. The method comprises the following steps: mixing a water-soluble manganese salt, a water-soluble iron salt, a doping auxiliary agent 1 and a water-soluble oxalate in a water-organic solvent system, and subjecting same to a coprecipitation reaction. The present invention further relates to a method for preparing a lithium iron manganese phosphate positive electrode material. The method comprises the following steps: mixing the ferromanganese oxalate precursor with a lithium source, a phosphorus source and a doping auxiliary agent 2, drying same, then subjecting same to low-temperature roasting to obtain a lithium iron manganese phosphate precursor, mixing the precursor with an organic carbon source, then drying the mixture, and subjecting the mixture to high-temperature sintering, so as to obtain a carbon-coated lithium iron manganese phosphate positive electrode material. The present invention further relates to the ferromanganese oxalate precursor and the lithium iron manganese phosphate positive electrode material prepared by these methods.

The invention discloses a special phosphorus removal agent for deep phosphorus removal and a preparation method and application thereof, and relates to the field of phosphorus removal agents and preparation methods thereof.The phosphorus removal agent is prepared from a porous precursor, an activating agent and a dispersing agent, and the porous precursor comprises at least one of aluminum oxide, iron oxide, calcium oxide and magnesium oxide; the activating agent comprises at least one of lanthanum salt, cerium salt, zircon salt, magnesium salt and ferric salt. By optimizing the composition of the porous precursor and activating treatment, the phosphorus adsorption capacity is remarkably improved, the phosphorus removal agent also plays a role in micro-flocculation in the process of mixed adsorption with sewage, a wet adding mode is adopted, the adding amount can be flexibly adjusted according to the phosphorus concentration condition of inlet water and outlet water, and the phosphorus removal efficiency is improved. The phosphorus removal agent can reduce the total phosphorus concentration in tail water of a sewage treatment plant to 0.5 mg / L or below.

The invention belongs to the technical field of catalysts, and relates to a surface-reconstructed heterojunction catalyst and a preparation method and application thereof. The preparation method comprises the following steps: dissolving cobalt salt, ferric salt and praseodymium salt in deionized water, heating and spraying on a carrier to prepare praseodymium-doped ferrocobalt layered double hydroxide; mixing the praseodymium-doped ferrocobalt layered double hydroxide with a phosphorus source, and calcining in an inert atmosphere to prepare praseodymium-doped CoP / Fe2P; and carrying out electrooxidation treatment on the praseodymium doped CoP / Fe2P, so as to prepare the Pr6O11 cluster modified CoFeOOH heterojunction catalyst. Through cooperation of three technologies of spray thermal deposition, phosphating and electrooxidation, stable construction and electrochemical activation of a heterogeneous interface are realized, the corrosion resistance and chlorine evolution resistance competitive capacity of the catalyst in a chlorine-containing alkaline system are remarkably improved, the current density of 100 mA. Cm <-2 > can be achieved only through 223 mV overpotential, and meanwhile, stable operation is performed for 500 h.

The invention discloses a high-stability iron-cerium flow battery and a preparation method of electrolyte, and belongs to the technical field of flow batteries. A positive electrolyte and a negative electrolyte are cerium salt and ferric salt, and are respectively mixed with nitrilotriacetic acid, ethylenediamine tetraacetic acid, trans-1, 2-cyclohexanediamine tetraacetic acid, 1, 3-propane diamine tetraacetic acid, N-(2-ethoxyl) ethylenediamine-N, N ', N'-triacetic acid, iminodiacetic acid, iminodisuccinic acid, succinic acid, N, N '-bis (2-hydroxyethyl)-N, N', N '-triacetic acid and N, N'-bis (2-hydroxyethyl)-N, N '-bis (2-hydroxyethyl)-N, N'-bis (2-hydroxyethyl)- N, N '-ethylenediamine disuccinic acid, aspartic acid or a derivative chemical thereof are coordinated to form an aqueous solution of the coordination compound. The positive electrolyte and the negative electrolyte are prepared from the same and equal chelating agent and supporting electrolyte, and the matching degree of the acid-base property of the positive electrolyte and the negative electrolyte is maintained; the auxiliary electrolyte is added, so that the viscosity difference between the positive electrolyte and the negative electrolyte is reduced, the transmembrane migration of water is reduced, and the conductivity is improved. The selected chelating agent is stably combined with iron and cerium, transmembrane transportation of active substances is inhibited, ion cross contamination among different electrolytes is reduced, and meanwhile side reactions are reduced. The price is low, and the charge-discharge performance and the cycle life of the iron-cerium flow battery are effectively improved at relatively low cost.

A method for preparing modified iron(III) phosphate, comprising the following steps: (1) preparing NH2-MIL-53(Al) nanoparticles, mixing the nanoparticles with a solvent, adding an acid solution, and heating and stirring the mixture to obtain hollow NH2-MIL-53(Al) powder; (2) using the hollow NH2-MIL-53(Al) powder to prepare a dispersion, mixing the dispersion with an iron salt solution, stirring and then drying the mixture, mixing the resulting powder with a phosphorus source solution, controlling the pH, and carrying out a reaction; and (3) carrying out sintering treatment on a material resulting from aging to obtain the modified iron(III) phosphate. Provided are iron(III) phosphate prepared according to the method and a positive electrode material. In the method, a hollow metal organic framework nanomaterial is used as a template to provide a micro reaction area for the synthesis of iron(III) phosphate, so that the microscopic morphology of the prepared iron(III) phosphate is restrained and controlled to prepare nanoscale iron(III) phosphate having a polyhedral structure.

The invention discloses a method for promoting bacillus soil microorganisms to actively absorb oxygen to degrade long-chain alkanes, which comprises the following steps: preparing a catalyst: uniformly mixing oil-containing soil, a carbon source, citric acid, ferric salt, hydrogen peroxide and distilled water, filtering, concentrating clear liquid to obtain a concentrated crystal substance, centrifugally cleaning the crystal substance, and drying to obtain the catalyst; the method comprises the following steps: mixing a catalyst with oil-containing soil, hydrogen peroxide and distilled water, and oscillating on a shaking table for Fenton pre-oxidation; after pre-oxidation, intermittent oscillation oxygenation is carried out, bioremediation is carried out on the petroleum-contaminated soil at normal temperature, and the three petroleum bacteria in the soil are activated. Through pre-oxidation treatment, consumption of soluble organic carbon by microorganisms in soil is stimulated, the active oxygen uptake process of the microorganisms is accelerated, and the carbon metabolism process is accelerated. Finally, the bacillus-like microorganisms capable of degrading the petroleum are activated, so that the aim of degrading the petroleum hydrocarbon in the soil for a long time is fulfilled.

The invention discloses a preparation method of iron-modified biochar, which comprises the following steps: soaking biochar in an acid solution, taking out the biochar, recovering the biochar to be neutral, drying, mixing the dried biochar with an iron salt solution, fully reacting, drying and calcining to obtain the iron-modified biochar; the mass ratio of the dried biochar to iron in the iron salt solution is 0.28-0.84. The iron modified biochar has excellent phosphorus adsorption capacity in practical application, and has excellent phosphorus solid storage and continuous release capacity; the iron modified biochar can be used for soil phosphorus fixation and slow release, water pollution prevention and / or phosphate fertilizer saving, and can effectively promote plant growth.

The invention discloses an efficient difunctional alkaline electrolysis water electrode which comprises a nickel net, an N deposition layer is deposited on the surface of the nickel net, and a NiFeW alloy layer is deposited on the surface of the N deposition layer. The invention further discloses a preparation method of the electrolyzed water electrode. The preparation method comprises the following steps: pre-treating the nickel net substrate; dissolving a nickel salt, a conductive salt and an additive in water to obtain a nickel electrodeposition solution; dissolving a nickel salt, an iron salt, a tungsten salt and an additive in water to obtain a nickel-iron-tungsten electro-deposition solution; and then the nickel net substrate is placed in a nickel electrodeposition solution to be subjected to constant-current deposition, a first electrode of an N deposition layer loaded on the nickel net substrate is obtained, the first electrode is placed in a nickel-iron-tungsten electrodeposition solution to be subjected to constant-current deposition, an N < iFeW > alloy layer loaded on the N deposition layer is obtained, and a finished electrode is obtained. The method has the advantages of low hydrogen evolution overpotential, low oxygen evolution overpotential, good stability, short-time deposition at room temperature, simplicity, easiness in control and low cost, and can be expanded to actual industrial application.

The preparation method comprises the following steps: S1, preparing a phosphoric acid solution, a hydrogen peroxide solution, a Ti salt, a phosphor salt solution and a ferrite solution; s2, Ti salt and the ferrite solution are mixed, and a titanium iron salt solution is obtained; mixing the phosphoric acid solution and the phosphorus salt solution to obtain a phosphorus source solution; s3, adding the titanium iron salt solution into a reaction kettle, and adding the hydrogen peroxide solution; s4, adding the phosphorus salt solution into the reaction kettle to obtain yellow slurry; s5, after the color of the slurry is heated to be white, white slurry is obtained; s6, carrying out solid-liquid separation on the white slurry to obtain an iron phosphate dihydrate filter cake; and S7, drying and calcining the iron phosphate dihydrate filter cake to obtain the Ti-doped battery-grade anhydrous iron phosphate. The titanium-doped iron phosphate is firstly prepared by a one-step method, the pH value of the reaction system is controlled by controlling the molar ratio of the iron element to all phosphorus elements in total phosphorus, ammonium phosphate and phosphoric acid in the reaction system, and the retention of the Ti element in the finished product and the regulation and control of the iron-phosphorus ratio in a specified range are ensured.

The invention relates to a lightweight porous nickel ferrite composite electromagnetic absorbing material and a preparation method thereof, and belongs to the field of electromagnetic wave absorbing materials, and the lightweight porous nickel ferrite composite electromagnetic absorbing material is a porous electromagnetic absorbing material prepared by high-temperature annealing of a mixture containing ferric salt, nickel salt, an acetic acid solution and chitosan. The lightweight and porous nickel ferrite composite electromagnetic absorbing material has both lightweight and electromagnetic absorbing properties.

A method for recovering heavy metals and soluble chlorine salts from fly ash generated by incineration of domestic waste. The method comprises the following steps: first, mixing fly ash with water and an acid, performing a leaching reaction when a pH value is controlled, improving the leaching efficiency of lead and zinc by means of air agitation, and measuring dissolved oxygen or redox potential to determine a leaching reaction endpoint; second, using a vulcanizing agent to recover leached heavy metals, and adjusting and monitoring the pH value of a leachate so as to control the adding amount of the vulcanizing agent; third, adding an alkali to adjust the pH value of the leachate so as to precipitate impurities such as aluminum and iron, and using an excessive amount of the vulcanizing agent to further remove heavy metals; and finally, adding an oxidizing agent and an iron salt coagulant into the leachate from which the heavy metals and impurities are removed, so as to remove divalent sulfur and arsenic, wherein the finally purified leachate can be used for recovering soluble chlorine salts. The method has a simple and efficient process, can significantly increase the recovery rate of heavy metals, and recovers heavy metals in the form of metal sulfides, thus facilitating subsequent separation treatment. The treated fly ash can be used as a raw material of cement, thus achieving efficient utilization of resources.

The invention discloses a method for preparing an iron-nickel-molybdenum-based electrocatalyst through combination of electrodeposition and rapid Joule heat and application of the method. The method comprises the steps that S1, a porous nickel substrate is pretreated, and the pretreated porous nickel substrate is obtained; s2, obtaining a nickel salt solution, a molybdenum salt solution and a ferric salt solution; s3, obtaining a mixed solution; s4, putting the mixed solution serving as electrolyte into a dual-electrode electrolytic tank, carrying out electro-deposition treatment by taking the pretreated porous nickel substrate as a cathode and an inert electrode as an anode, and washing and drying to obtain a Fe-Ni-Mo-LDH precursor; and S5, carrying out Joule thermal pyrolysis treatment on the Fe-Ni-Mo-LDH precursor, so as to obtain the iron-nickel-molybdenum based electrocatalyst. The preparation method can effectively regulate and control the size structure of the catalyst, and is suitable for preparing iron-nickel-molybdenum-based electrocatalysts with different substrates and different sizes; and the electrocatalyst has the advantages of uniform and stable nanostructure and high loading capacity. Meanwhile, the preparation method is short in reaction time, high in heating efficiency, high in repeatability and suitable for industrial large-scale production.

The invention provides a method for degrading organic phosphorus and recycling phosphorus in water in an ozone oxidation system. According to the method, a mode of adding iron or iron salt solution step by step is innovatively adopted, so that the degradation rate of phosphorus-containing organic matters in water, the generation rate of phosphate radicals and the removal of total phosphorus in water are remarkably improved. Besides, the treatment effect is evaluated by monitoring the organophosphorus mineralization rate (taking the generation amount of phosphate radicals as an index) and the removal rate of total phosphorus in water, experiments show that the method can increase the organophosphorus mineralization rate by 30% or above, and the removal rate of total phosphorus reaches 95%. Compared with the conventional one-time addition of iron or iron salt, the method has the advantages that the mineralization rate of organophosphorus and the removal rate of total phosphorus are effectively improved through a step-by-step addition strategy, the direct precipitation of an organophosphorus intermediate product is promoted, the use amount of ozone and the addition amount of iron are remarkably reduced, the reaction time is greatly shortened, and the recovery efficiency of phosphorus resources is further improved. The method is low in cost and suitable for advanced treatment of organic phosphorus-containing wastewater in the industries of pesticides, electroplating and the like.

The invention relates to the technical field of material preparation, and discloses a magnetic basalt fiber reinforced wear-resistant self-lubricating coating and a preparation method thereof, and a coating and a preparation method thereof, and the preparation method comprises the following steps: step 1, treating short-cut basalt fibers with an acid and / or alkali solution, mixing with an iron salt solution to obtain a reaction solution, carrying out hydrothermal reaction to obtain the magnetic basalt fiber loaded by the magnetic nanoparticles; step 2, adding a filler into the resin matrix solution, dispersing, and grinding to obtain resin slurry; and 3, adding the magnetic basalt fiber in the step 1 into the resin slurry in the step 2, adding a curing agent, and uniformly mixing to obtain the required coating. According to the method, the contact behavior and the abrasion mechanism of a friction pair are optimized, the friction coefficient and the abrasion rate are reduced, the tribological performance of the obtained coating is improved, the service life of a mechanical kinematic pair is prolonged, and the reliability and the stability of equipment operation are improved.

The invention relates to the technical field of electro-catalysis and hydrogen energy, in particular to a modified LDH-based catalyst and a preparation method and application thereof. The preparation method comprises the following steps: mixing trimesic acid, water, an organic solvent, a nickel salt, a cobalt salt and an iron salt, carrying out electro-deposition, washing and drying to obtain a NiFeCo-LDH (TA) catalyst; the preparation method comprises the following steps: soaking a NiFeCo-LDH (TA) catalyst in a silver salt solution, washing and drying to obtain the modified LDH-based catalyst. The modified LDH-based catalyst provided by the invention can effectively resist chloride ion corrosion and inhibit dissolution of active metals in layered double hydroxides (LDH) under high current density in seawater, can reach industrial grade current density under relatively low overpotential, and can stably run for more than 1000 hours.

The invention belongs to the technical field of catalyst preparation and wastewater treatment, and particularly relates to an iron-nitrogen co-modified biochar catalyst as well as a preparation method and application thereof. Comprising the following steps: (1) pyrolyzing a biomass precursor at 200-400 DEG C in an inert gas atmosphere to obtain low-temperature biochar; (2) sufficiently mixing an iron salt solution, an organic nitrogen source and the low-temperature biochar through an impregnation method to obtain a mixed solution, and drying the mixed solution to obtain an iron-nitrogen co-modified biochar precursor; and (3) pyrolyzing the iron-nitrogen co-modified charcoal precursor at 600-1000 DEG C in an inert gas atmosphere to obtain the iron-nitrogen co-modified charcoal catalyst. The iron-nitrogen co-modified biochar catalyst is used for treating organic matters in high-salt organic wastewater, can realize catalytic polymerization removal of the organic matters, and effectively solves the problems that the number of active sites of biochar is limited, the electron transfer efficiency is relatively low, and the utilization efficiency of an oxidant in a persulfate activation technology is low and the mineralization ability is poor.

The present invention relates to a crop nutrition and fortifying composition comprising: i. Elemental sulfur; ii. One or more water insoluble or water soluble magnesium salts or derivatives or mixtures thereof; iii. One or more water-insoluble or water-soluble potash fertilizers or salts or derivatives or mixtures thereof; iv. One or more water insoluble or water soluble iron salts or derivatives or mixtures thereof; v. One or more water insoluble or water soluble zinc salts or derivatives or mixtures thereof; vi. One or more water-insoluble or water-soluble boron salts or derivatives or mixtures thereof; vii. At least one trace element selected from the group consisting of water-insoluble or water-soluble vanadium salts or derivatives or mixtures thereof and water-insoluble or water-soluble selenium salts or derivatives or mixtures thereof; and viii. One or more excipients wherein the composition comprises microparticles having a size in the range of 0.1 to 50 microns, and wherein the total content of the water-soluble salts, derivatives or mixtures in the composition does not exceed 80% of the total weight of the composition. The invention also relates to a method for preparing the crop nutrition and fortifying composition and a method for treating a plant, a seed, a crop, plant propagation material, a locus, parts thereof or soil with the crop nutrition and fortifying composition.

The invention discloses a step-by-step removal method for thallium and arsenic in lead-zinc smelting waste acid, which comprises the following steps: adding a calcium-containing precipitant into the lead-zinc smelting waste acid for neutralization and precipitation to obtain a neutralization and precipitation filtrate and a neutralization and precipitation filter residue; adding a calcium remover into the neutralized and precipitated filtrate to carry out calcium removal reaction to obtain calcium-removed filtrate and calcium-removed slag; adding an oxidizing agent I and a catalyst into the calcium-removed filtrate, controlling the pH value of the oxidation process to be 9.0-11.5 by using alkali liquor, carrying out selective oxidation thallium removal, and filtering to obtain thallium-removed filtrate and thallium-removed slag; and adding iron salt into the thallium-removed filtrate for deep arsenic removal to obtain effluent and arsenic-removed slag. According to the method, thallium and arsenic in the contaminated acid can be removed step by step, so that the concentration of arsenic and thallium in effluent stably reaches the standard for a long time while thallium slag and arsenic slag are separated.

The invention discloses a cathode roller with a honeycomb surface structure. A precise honeycomb micro-pattern structure is arranged on the surface of the cathode roller. The invention also discloses a method for manufacturing alloy foil by using the cathode roller, which comprises the following steps: dissolving ferric salt in ultrapure water to obtain a ferric salt solution; dissolving nickel salt in ultrapure water to obtain a nickel salt solution; mixing the two solutions and filtering; preparing various additive solutions, mixing all the additive solutions with the obtained iron-nickel solution to obtain an electrolyte, filtering the electrolyte, and transferring the filtered electrolyte into an electrolytic cell of a crude foil engine; and applying current to a cathode roller and an anode plate which are separately arranged in the electrolytic bath, electrically depositing iron and nickel on the surface of the cathode roller, and rolling through a roll-to-roll process to obtain the iron-nickel alloy foil. The alloy foil manufactured by the method has the characteristics of low surface roughness, high tensile strength and high ductility.

The invention discloses a preparation method of a graphene composite lithium iron phosphate positive electrode material, and relates to the technical field of positive electrode materials, and the preparation method comprises the following steps: S1, adding a graphene oxide into deionized water, and stirring to obtain a solution I; s2, dissolving ferric salt in deionized water according to the mass ratio of the ferric salt to graphene oxide of 1: 0.05, adding the solution I, and stirring to obtain a solution II; s3, sequentially adding phosphoric acid, ethylene glycol and lithium salt into the solution II according to the molar ratio of ferric salt to phosphoric acid to lithium salt of 1: 1: 3, and stirring to obtain a solution III; s4, putting the solution III into a reactor, covering and sealing, heating in a gradient water bath, soaking a product obtained in the water bath with deionized water, and drying in a vacuum freeze dryer; s5, vacuum drying; the crystallinity and morphology of the product are optimized by accurately controlling the water bath temperature and time; and a uniform and ordered crystal structure is formed by staged water bath, so that the electrochemical performance of the product is improved.

The invention provides a self-supporting carbon-based material loaded with iron nanoparticles as well as a preparation method and application of the self-supporting carbon-based material, and belongs to the technical field of preparation and application of an electrocatalyst for removing nitrate in sewage. The preparation method of the self-supporting carbon-based material loaded with the iron nanoparticles comprises the following steps: providing a carbon felt subjected to acid pickling and water bath heating; the method comprises the following steps: mixing an iron precursor and urea in a solvent to obtain a mixed solution containing iron salt; and mixing the carbon felt with the mixed solution containing the iron salt, and carrying out a hydrothermal reaction to obtain the self-supporting carbon-based material loaded with the iron nanoparticles. When the iron nanoparticle-loaded self-supporting carbon-based material provided by the invention is used as a cathode for electro-catalysis of nitrate-containing wastewater, a good removal rate and ammonia nitrogen selectivity are achieved, and the catalyst can keep relatively high nitrate nitrogen removal and ammonia nitrogen production effects under the conditions of acidity, neutrality, alkalinity and different initial nitrate concentrations; the method has the advantages of high removal efficiency, good ammonia nitrogen selectivity, strong stability and the like.

The invention discloses a colored magnetic particle preparation method, a colored magnetic particle, a magnetic microcapsule and a magnetic film, and relates to the technical field of magnetic particle preparation. According to the preparation method, ferric salt and an alkaline substance are adopted, a ferroferric oxide precursor precipitation solution is generated through a coprecipitation method, surface modification is conducted through oleic acid, the dispersity and stability of particles in an organic system are enhanced, a solvent is adopted for washing and drying, and the purity and chemical stability of the particles are further improved; subsequently, mixing the modified nano ferroferric oxide, a dye, a high polymer and a functional additive to obtain the colored magnetic particle. The method has the advantages that the preparation process is simple, and the prepared colored magnetic particles are excellent in dispersity, stability and functionality.

The present invention discloses a layered metal hydroxide composite catalytic material, its preparation method and application. The composite catalytic material comprises a carrier carbon nanotube and a metal hydroxide loaded on the carbon nanotube, and the metal is iron, cobalt and nickel. Preparation method: (1) Dissolve nickel salt, cobalt salt, iron salt and urea in an alcohol solution, stir evenly, then add carbon nanotubes, and continue to stir evenly to obtain a mixed solution; (2) Carry out a solvothermal synthesis reaction on the mixed solution obtained in step (1), filter, wash and dry after the reaction is completed to obtain the layered metal hydroxide composite catalytic material. The carbon nanotubes are introduced into the layered metal hydroxide in this composite catalytic material, reducing the precipitation of metal ions, avoiding the aggregation of hydroxides, improving the stability and catalytic activity of the catalytic material, and being used for activating persulfate to degrade organic pollutants, realizing the efficient activation of persulfate so as to improve the degradation rate of pollutants.

The present application relates to a chelated iron desulfurizer, which is composed of a high-price soluble iron salt, a chelating agent, a pH buffer and water, wherein the chelating agent is a compound of sodium polyetheramine tetraacetate and at least one of N,N-diethylcarboxylic acid-based ethylenediamino-3-hydroxysuccinic acid, a polycarboxylic acid chelating agent or an amino acid-derived chelating agent; or the chelating agent is a compound of tetrasodium N,N-diethylcarboxylic acid-based ethylenediamino-3-hydroxysuccinic acid and at least one of sodium polyetheramine tetraacetate, a polycarboxylic acid chelating agent or an amino acid-derived chelating agent. Compared with the existing commonly used desulfurizers EDTA or NTA, the chelating ability of the present application's chelated iron desulfurizer is significantly improved, the iron ion regeneration ability is significantly enhanced, and the desulfurization effect is comparable to EDTA or NTA.

The present invention belongs to the technical field of batteries. Disclosed are an iron(III) phosphate material, a preparation method therefor, and a use thereof. The iron(III) phosphate material comprises a carbon quantum dot core located internally and an iron(III) phosphate shell formed on the surface of the carbon quantum dot core, and the surface of the iron(III) phosphate shell is provided with a carbon coating layer formed from a carbon-containing dispersing agent. The iron(III) phosphate material is nanoscale iron(III) phosphate and has a uniform crystal size. The preparation method therefor comprises the following steps: mixing a first mixed solution containing a divalent iron salt and carbon quantum dots, a second mixed solution containing a phosphate and a dispersing agent, and an oxidizing agent to undergo a reaction to obtain iron(III) phosphate dihydrate; and annealing and calcining the iron(III) phosphate dihydrate. The iron(III) phosphate material can be further used for preparing a lithium iron phosphate positive electrode material and a battery.