32 results about "Oxidizing acid" patented technology

The invention discloses a method for separating and recovering selenium and mercury from acid mud containing selenium and mercury. The method comprises the following steps: mixing the acid mud containing selenium and mercury with water, performing wet ball milling, filtering and drying to obtain a ball milling material; adding a hydrogen peroxide solution into the ball-milled material, adding hydrochloric acid to adjust the acidity, carrying out oxidation acid leaching, and carrying out solid-liquid separation to obtain selenium-containing mercury liquid and selenium-removed mercury slag; adding thiourea into the selenium-containing mercury liquid for selective reduction, and performing solid-liquid separation to obtain crude selenium and reduction liquid; zinc powder is added into the reduction liquid for mercury replacement and precipitation, and crude mercury and precipitation liquid are obtained after solid-liquid separation; wherein the selenium-removed mercury slag and the precipitation solution are subjected to centralized treatment. The method is simple in process, convenient to operate and easy to process, selenium and mercury in the acid mud containing selenium and mercury can be removed at a time, efficient separation and recovery of selenium and mercury in the acid mud containing selenium and mercury are achieved, harmless treatment of hazardous waste and effective utilization of resources are achieved, and the method conforms to the concept of green sustainable development.

This invention discloses a method for purifying single-walled carbon nanotubes (SHU). The purification method includes the following steps: mixing crude SHU with a non-oxidizing acid solution in a reaction vessel; introducing gas into the reaction vessel; heating the reaction; and separating the solid and liquid phases to obtain the final product. This invention uses a non-oxidizing acid and gas bubbles to synergistically purify SHU, ensuring effective removal of metallic impurities and amorphous carbon while protecting the SHU from structural damage.

The invention discloses a method and a device for pre-treating recycled acid liquor to remove oxalate, and the method comprises the following steps: adding oxalic acid and / or soluble oxalate into acid waste liquor to enable reaction liquor to generate new oxalate precipitate, and then carrying out solid-liquid separation to obtain new oxalate filter residue and acid filtrate; the method is characterized by further comprising the following steps: (1) directly carrying out oxidation reaction on the acidic filtrate or carrying out oxidation reaction after blending for at least 2 hours, so that oxalate C2O4 < 2-> or other organic impurities in the acidic filtrate are partially or completely removed through chemical reaction to obtain oxidized acidic filtrate; and (2) directly feeding the oxidized acidic filtrate or feeding the oxidized acidic filtrate into a corresponding circuit board acidic corrosion production line as a regenerated metal corrosion liquid for recycling. According to the method, the oxalate impurity content index or the oxalate impurity and organic matter impurity index in the acidic filtrate obtained through oxalic acid treatment is reduced after oxidation treatment.

The application discloses a method for reducing acid consumption in copper soot treatment and preparing electroplating-grade copper sulfate, and belongs to the technical field of comprehensive utilization of non-ferrous metal resources. The method comprises five steps of oxidizing acid leaching, cooling crystallization, redissolving and one-stage impurity removal, two-stage impurity removal and copper recovery, and refining and recrystallization. The application effectively inhibits copper arsenate precipitation by constructing a high-acid saturated leaching system, realizes the crystallization separation of copper sulfate and leaching solution, thereby avoiding the traditional neutralization and impurity removal process, and significantly reducing alkali consumption. The synergistic precipitation characteristics of arsenic, antimony and bismuth in a strong acid system are utilized to realize efficient enrichment of valuable metals. Two-stage impurity removal is adopted, and copper-containing residues are returned to leaching to reduce copper loss. Calcium impurities are removed by adding crystal seeds to improve the purity of copper sulfate products. The application has the advantages of low acid and alkali consumption, high copper recovery rate, high product added value, simple process flow, strong recycling, etc., and is suitable for resource utilization of copper smelting soot.

The invention discloses a method for efficiently reducing elemental selenium from selenium-containing leachate based on ferrous sulfate, which comprises the following steps: taking the selenium-containing leachate obtained by oxidation and acid leaching, and adjusting the acidity of the leachate to 0.5-1.1 mol / L; ferrous sulfate is added into the acid-adjusted selenium-containing leachate according to the liquid-solid ratio of 2 mL: (1.0-1.4) g for a reduction reaction, the reduction reaction temperature ranges from 70 DEG C to 90 DEG C, the reduction reaction time ranges from 40 min to 80 min, and a reaction product I is obtained; and separating the precipitate of the reaction product I, washing and drying to obtain the elemental selenium. According to the method disclosed by the invention, the elemental selenium is extracted by reducing the selenium-containing leachate by adopting ferrous sulfate, and the reduction rate of selenium can reach 91% or above under limited conditions; under optimized conditions, the selenium reduction rate can reach 95.87%, which is significantly superior to that of existing processes such as a microbiological method.

This invention discloses a method, product, and application for the separation of astatine-211 in an aqueous phase based on valence state regulation. The method includes: passing a solution of astatine-211 containing a strong oxidizing acid through a sulfur-containing solid support, causing specific adsorption of positively valence astatine-211; eluting with a water-soluble reducing agent to reduce astatine-211 to astatine anions, obtaining an aqueous astatine-211 eluent. The entire process is carried out in the aqueous phase, requiring no organic solvents and avoiding radionuclide volatilization loss due to heating and evaporation. This invention also provides an eluent composition obtained by this method, sodium astatide injection, astatine-211-labeled radiotargeting drugs and their preparation methods, as well as the application of this eluent composition in the preparation of drugs for treating NIS-positive diseases. This invention achieves highly selective separation and mild, rapid elution of astatine-211, and the product exhibits excellent biocompatibility and radiation stability, and can be used directly or after simple activation to prepare targeted α-therapy drugs.

This application discloses a method for detecting the content of elemental metal foreign particles in a positive electrode active material, comprising the following steps: mixing the positive electrode active material to be detected with a first solvent to obtain a first mixture; sieving the obtained first mixture and collecting the first solid component remaining on the sieve after sieving; mixing the obtained first solid component with a weak oxidizing acid solution, an antioxidant, and a corrosion inhibitor solution and reacting to obtain a second mixture; separating the obtained second mixture to obtain a second solid component including elemental metal foreign particles; scanning the obtained second solid component with a scanning device and counting the number of elemental metal foreign particles, and calculating the mass of the elemental metal foreign particles and their content in the positive electrode active material based on the number of elemental metal foreign particles.

This invention relates to a method for smelting nickel-iron alloys, comprising the following steps: the nickel-iron alloy is subjected to oxidative acid leaching to obtain a leaching solution and leaching residue; the obtained leaching solution is subjected to chromium removal to obtain chromium-removed residue and chromium-removed filtrate; a first oxidant, phosphoric acid, and the obtained chromium-removed filtrate are mixed to remove iron to obtain ferric phosphate and an iron-removing solution; a trivalent iron salt is mixed with the obtained iron-removing solution to remove phosphorus to obtain a phosphorus-removing solution and ferric phosphate residue; the obtained phosphorus-removing solution is subjected to impurity removal, and the obtained impurity-removed solution is used to prepare a ternary precursor. The method provided by this invention eliminates the need for extraction, reducing the processing cost of nickel-iron alloys, and also enables the iron in the nickel-iron alloy to be made into battery-grade ferric phosphate, while the nickel can be used to prepare precursors, resulting in high overall benefits.

This invention provides an M with precise atomic number. n Nanocluster catalysts, their preparation methods, and applications. Using Ketjen black as an innovative platform, oxidizing acid treatment was employed to obtain Ketjen black oxide with a surface rich in oxygen-containing functional groups. Utilizing the electrostatic and coordination interactions between its negatively charged surface and the clusters, atomically precise Mo nanocluster catalysts were prepared. n Nanocluster catalysts. The active metal M is highly and stably dispersed on the surface of an oxygen-rich Ketjen black oxide support under electrostatic and coordination interactions. The prepared process is simple and successfully overcomes the problems of easy aggregation and poor stability of nanoclusters during loading. It can be used in selective hydrogenation reactions, exhibiting excellent hydrogenation activity and selectivity, outstanding catalytic performance, easy recovery and reuse, and good stability.

The invention discloses a comprehensive utilization method of silicon-manganese alloy smelting smoke dust, which belongs to the field of mineral processing and secondary resource comprehensive utilization, and comprises the following steps: adding water into the silicon-manganese alloy smelting smoke dust, stirring for size mixing, carrying out water leaching, recovering soluble K, Rb and other components, filtering, adding water into the filter residue again for size mixing, carrying out low-intensity magnetic separation and high-intensity magnetic separation, and carrying out high-intensity magnetic separation and high-intensity magnetic separation; magnetic Fe minerals and Mn minerals are recovered, a certain amount of non-oxidizing acid is added after ore pulp concentration of magnetic separation tailings is adjusted, Zn, Cu and other heavy metal ions are recovered through acid leaching, after acid leaching tailings are dehydrated, auxiliary materials are added for sintering, and the sintered tailings are returned to a silicon-manganese alloy smelting furnace for secondary smelting. The method is reasonable in process, simple in flow, high in valuable component recycling rate, easy to implement and beneficial to achieving reduction and recycling of the smelting smoke dust from the source.

This invention discloses a method for purifying 2,5-furandicarboxylic acid (FDCA), belonging to the field of chemical technology. The purification method includes the following steps: crude 2,5-furandicarboxylic acid is subjected to alkali dissolution, oxidation, acidification, stirring, pulping, washing, and drying to obtain pure 2,5-furandicarboxylic acid. In the acidification crystallization process and the pulping and washing process, by selecting appropriate conditions such as the acidification reaction temperature, the oxygen content of the oxidation gas, the pulping and washing temperature, and the pulping and washing time, the purity of the obtained FDCA can reach 99.99%. Moreover, no organic solvents are used, meeting the requirements of polymerization-grade products. Furthermore, and more importantly, the FDCA product obtained by this invention has excellent particle characteristics, high flowability, and high bulk density, which is highly beneficial for downstream polymerization reactions and also facilitates the packaging and transportation of the FDCA product.

This invention discloses a purification method for n-hexane for spectral analysis and a modified activated carbon used in this method, belonging to the field of high-purity organic solvent purification technology. The method includes: chemical pre-neutralization, stepwise pre-dehydration, deep adsorption, and nitrogen-protected precision distillation. Chemical pre-neutralization uses an alkaline solution to remove acidic impurities; stepwise pre-dehydration uses molecular sieves to reduce the moisture content to below 0.015%wt; deep adsorption uses supported oxidatively functionalized modified activated carbon to selectively adsorb unsaturated hydrocarbons and fluorescent impurities; nitrogen-protected precision distillation further separates residual isomers. The modified activated carbon is activated by impregnation with oxidizing acids such as sodium hypochlorite, introducing oxychlorine functional groups onto its surface, resulting in a BET specific surface area ≥1200 m² / g. The product produced by this purification method has a main content ≥99.995%wt, and all optical indicators meet the T / CRIAC0114-2026 spectral grade standard, making it suitable for continuous industrial production.

The invention relates to the technical field of chemical catalysis, in particular to a phosphotungstic acid modified titanium silicalite molecular sieve catalyst and a preparation method and application thereof.According to the catalyst, a titanium silicalite molecular sieve (TS-1) serves as a carrier, phosphotungstic acid (HPW) is loaded through an impregnation method to form a bifunctional active center, then surface hydrophobic modification is conducted through a silanization reagent, and the phosphotungstic acid modified titanium silicalite molecular sieve catalyst is obtained. And an oxidation-acidic concerted catalysis-hydrophobic microenvironment regulation composite system is constructed. According to the method, firstly, a bifunctional active center is constructed by accurately controlling the loading process of phosphotungstic acid on a TS-1 molecular sieve, and then hydrophobic modification is performed on the surface of the catalyst by adopting a silanization reagent, so that the problem of dissolution loss of phosphotungstic acid in the reaction process is effectively solved while the high activity and high selectivity of the catalyst are maintained; and the cycling stability of the catalyst is obviously improved, so that high-selectivity oxidation of cyclopentene to prepare glutaraldehyde is realized.

The invention provides a method for recovering tin and lead in a waste circuit board, and relates to the technical field of resource recovery. The recovery method provided by the invention comprises the following steps: stripping electronic elements on the waste circuit board, crushing, sorting and pouring to obtain a metal plate; the metal plate is subjected to electrolytic copper separation, and then gold separation and silver separation are conducted to obtain mixed slag; stirring and reacting the mixed slag in a composite acid solution, and separating to obtain a lead-containing solution and a tin-containing precipitate; stirring and reacting the tin-containing precipitate in an alkali solution, and separating a tin-containing solution; and respectively desolventizing the tin-containing solution and the lead-containing solution to recover tin and lead. According to the invention, tin and lead in the waste circuit board can be efficiently separated and recovered, and meanwhile, the use of strong oxidizing acid is reduced, so that the pollution to the environment in the recovery process is reduced.

The invention provides a harmless and resourceful treatment method for a high-arsenic rare noble metal material, and belongs to the technical field of noble metal refining. The treatment method comprises the following steps that S1, oxidation acid leaching is conducted on the high-arsenic rare and precious metal material, then solid-liquid separation is conducted, and arsenic-containing acid leaching liquid and arsenic-containing leaching residues are obtained; s2, carrying out catalytic reduction reaction on the arsenic-containing acid leachate to separate out arsenic in the solution in the form of elemental arsenic, and separating to obtain crude elemental arsenic and arsenic-removed liquid; s3, the arsenic-containing leaching residues are subjected to oxygen-enriched reduction smelting, arsenic in the arsenic-containing leaching residues is fixed in an arsenic-iron alloy phase, arsenic-iron white matte is formed, and meanwhile precious metal is enriched; and S4, extracting from the arsenic-removed liquid, and carrying out electrodeposition to recover scattered metal indium. Through close cooperation of the steps, the operation is relatively simple and convenient, the procedures are closely connected, and the method has a good industrial application prospect.

This disclosure relates to a graphene oxide-based composite material, its preparation method, and its uses. The method includes: S1, mixing graphite, potassium permanganate, and a strong oxidizing acid to obtain a mixture; S2, heating the mixture, and then subjecting the heated material to microwave calcination. The preparation method of this disclosure uses a microwave calcination process to reduce graphene oxide. No water is added during the entire preparation process, thus avoiding wastewater discharge and NO emissions. x To address a range of issues, including emissions, the resulting redox graphene-based composite material exhibits excellent desulfurization performance.

A method of processing a diamond to obtain vacancy-based defects and vacancy-based clusters includes the steps of: providing an artificial single-crystal diamond with {001} faces, the artificial single-crystal diamond having a substitutional nitrogen concentration above or equal to 100 parts per million; conditioning surfaces of the diamond by boiling under reflux of a solution comprising nitric, sulphuric, and an oxidizing acid, such as perchloric acid or hydrogen chloride; irradiating the diamond with neutrons; conditioning the surfaces of the diamond at a temperature above or at least 100° C., under a constant gas flow with a pressure above or equal to atmosphere pressure, such as at least 1 bar; annealing the diamond, thereby obtaining a diamond with vacancy-based defects and vacancy-based clusters. A system for processing a diamond utilizes the method.

The invention discloses a purification method of a single-walled carbon nanotube. The purification method comprises the following steps: S1, mixing and stirring oxidizing acid and a single-walled carbon nanotube crude product, and refluxing I to obtain a suspension; and S2, mixing a non-oxidizing acid and the suspension, continuing reflux II, and carrying out solid-liquid separation to obtain the product. According to the method, oxidizing acid and non-oxidizing acid are combined, firstly, the oxidizing acid and a single-walled carbon nanotube crude product are subjected to reflux reaction, a carbon coating layer of metal oxide is rapidly and effectively opened, and most amorphous carbon is degraded. The non-oxidizing acid is added for reflux, the non-oxidizing acid dissolves the exposed metal catalyst with the mild protonic acid characteristic and actively inhibits excessive erosion to the carbon tube body, amorphous carbon and fully exposed residual metal catalyst particles can be fully dissolved and removed, and the high purity is achieved while the residual metal catalyst particles are fully exposed. The inherent structure and intrinsic performance of the carbon nano tube are protected to the maximum extent, and deep removal of metal impurities is achieved.

The present application relates to a kind of methods for leaching valuable metals from iron-containing cobalt copper nickel alloy, comprising the following steps: (1) the iron-containing cobalt copper nickel alloy is melted, and alloy melt is formed;(2) phosphorus-containing material is added to the alloy melt, and homogeneous is kept for a period of time, and phosphorus alloy melt is obtained;The mass of phosphorus-containing material added is 0.03 times-0.5 times the mass of iron-containing cobalt copper nickel alloy;(3) the phosphorus alloy melt of step (2) is atomized and powdered, and phosphorus alloy powder is obtained, the mass fraction of P in phosphorus alloy powder is ≥3%, and particle size is ≤150 microns;(4) the phosphorus alloy powder of step (3) is oxidized and acid leached with sulfuric acid;During the leaching process, oxygen-containing gas is introduced.The leaching procedure provided by the present application for directly acid leaching cobalt and copper does not need to be pressurized or add chlorine, chloride ion and related catalysts, the equipment is easy to realize, and the comprehensive economic and environmental advantages of the process are very significant.

The application discloses a pickling and passivation process for a stainless steel equipment surface and relates to the technical field of stainless steel purification, and comprises the following steps: S1, pretreatment, sequentially performing degreasing and water washing operations on the surface of the stainless steel equipment; S2, pickling treatment, immersing the pretreated stainless steel equipment into a pickling solution, pickling for 10-20 min at 40-50 DEG C, and gently stirring at a speed of 30-50 r / min every 5 min during the pickling; S3, passivation treatment, immersing the pickled stainless steel equipment into a passivation solution; and S4, post-detection, detecting the surface of the treated stainless steel equipment, and requiring that the surface roughness Ra is less than or equal to 0.8 mu m, the passivation film adhesion grade is greater than or equal to 1, and there is no rust after a 48-h neutral salt spray test. The pickling solution adopts a phosphoric acid-organic acid composite system, replaces a traditional strong oxidizing acid or a hydrofluoric acid system, and is supplemented with a compounded corrosion inhibitor, so that the corrosion rate of the pickling solution on the stainless steel base material can be significantly reduced, defects such as pitting and etching pits can be avoided, and the flatness of the base material surface can be ensured.

This invention discloses a high-impurity copper electrolytic anode mud treatment technology, belonging to the field of non-ferrous metal hydrometallurgical technology. Addressing the problem of high copper, nickel, selenium, and tellurium content and difficulty in precious metal recovery in anode mud, this invention provides a magnetic field-assisted treatment method: after crushing and ball milling the anode mud into a slurry, oxygen and hydrogen peroxide are introduced under a vertical magnetic field for oxidative acid leaching, efficiently recovering nickel, selenium, and tellurium; the leached residue is then reduced and enriched with sodium bisulfite and iron powder under a parallel magnetic field, and finally dissolved stepwise with aqua regia and nitric acid to obtain gold and silver powder. This invention achieves copper and nickel leaching rates ≥96.8%, selenium and tellurium leaching rates ≥70%, and enriched slag with a gold grade ≥5000 g / t and a silver grade ≥20%, offering advantages such as a short process, low energy consumption, and high recovery rate.

The invention relates to the technical field of water treatment and precious metal separation and purification, and particularly discloses a method for synchronously removing, separating and purifying precious metal silver and harmful metal in wastewater. The method comprises the following steps: (1) adding an adsorbent containing amidoxime groups on the surface into wastewater, and carrying out adsorption treatment; (2) adding the adsorbent after adsorption into a primary desorption solution of non-oxidizing acid, and carrying out primary desorption to remove hetero-ions except silver; and (3) the adsorbent obtained after primary desorption is added into a secondary desorption solution of oxidizing acid, secondary desorption is conducted, and a high-purity silver solution is obtained. The method is based on the principle that amidoxime groups can spontaneously reduce silver ions into acid-resistant silver nanoparticles, and other metal ions form acidolysis complexes. The method is simple and convenient, an external electric field or a reducing agent is not needed, water purification and high-purity recovery of silver are achieved, and remarkable economic and environmental benefits are achieved.

The invention relates to the technical field of dielectric materials, in particular to a modified g-C3N4 / PEI composite film and a preparation method and application thereof. The preparation method comprises the following steps: modifying g-C3N4 in a strong oxidizing acid solution to obtain modified g-C3N4; the modified g-C3N4 is of a porous structure, and the surface of the modified g-C3N4 contains-OH and-COOH; and dispersing the modified g-C3N4 into a PEI dissolving solution, carrying out film formation on the obtained dispersion solution, and curing to obtain the modified g-C3N4 / PEI composite film. According to the modified g-C3N4 / PEI composite film provided by the invention, the dielectric constant is remarkably enhanced while high breakdown strength of a polymer dielectric medium is maintained, so that collaborative optimization of high energy storage density and high charge-discharge efficiency is obtained.

The invention relates to the technical field of purification of cold hydrogenated slurry high-boiling residues, and provides a modified coconut shell activated carbon adsorbent as well as a preparation method and application thereof. The modified coconut shell activated carbon adsorbent is characterized by comprising a coconut shell activated carbon substrate; the alkaline nitrogen-containing functional group is covalently bonded on the coconut shell activated carbon substrate. The alkaline nitrogen-containing functional group is stably loaded on the surface of the activated carbon in a covalent bond mode instead of simple physical impregnation, and efficient and high-selectivity adsorption is achieved through the acid-base coordination effect of the alkaline nitrogen-containing functional group and aluminum and titanium impurities. The preparation method of the modified coconut shell activated carbon adsorbent comprises the following steps: carrying out first reaction on a coconut shell activated carbon substrate and oxidizing acid to obtain oxidized coconut shell activated carbon; and carrying out a second reaction on the oxidized coconut shell activated carbon and an amine-containing compound to obtain the modified coconut shell activated carbon adsorbent. The method is simple in steps, mild in reaction conditions and easy to industrialize.

The application discloses a kind of triphenyl unit copolymer structure's basic anion exchange membrane and preparation method thereof, biphenyl, m-triphenyl and 1,2-diphenyl ethane are dissolved in first organic solvent and strong oxidizing acid and piperidone are sequentially added to carry out polycondensation reaction, after reaction, the reaction product is quenched, washed, dried, and solid powder is obtained;The solid powder is dissolved in second organic solvent and potassium carbonate and methyl iodide are added, and the reaction is carried out in dark at room temperature, after reaction, the reaction product is washed, dried, and polymer powder is obtained;The polymer powder is dissolved in second organic solvent to obtain casting liquid, the casting liquid is cast into film, and the triphenyl unit copolymer structure's basic anion exchange membrane is obtained.The triphenyl unit copolymer structure's basic anion exchange membrane has strong mechanical strength, high ionic conductivity and high chemical stability.

This invention provides a method for the direct oxidation of nitrobenzaldehyde to nitrobenzaldehyde, belonging to the field of organic synthesis technology. The method includes the following steps: mixing nitrobenzaldehyde, an organic solvent, a catalyst, an oxidant, and a strongly oxidizing acid, and carrying out an oxidation reaction to obtain nitrobenzaldehyde; the catalyst is a heteropolyacid salt; the oxidant is Mn₂O₃, sodium hypochlorite, or hydrogen peroxide. This invention develops a highly efficient metal heteropolyacid salt catalyst, which, in conjunction with the oxidant, achieves highly selective direct catalytic oxidation of nitrobenzaldehyde to nitrobenzaldehyde, avoiding the numerous steps, severe over-oxidation, and large amounts of bromine / acid-containing wastewater generated by traditional methods. The direct oxidation method is simple, has high chemical selectivity, produces no wastewater, and the reaction medium can be recovered, showing broad application prospects.

This invention provides a method for preparing cellulose-based hard carbon anode materials and their applications, belonging to the field of sodium-ion battery anode material preparation technology. The method includes: preparing a strong oxidizing acid solution, adding cellulose-based raw materials to the solution, ultrasonically vibrating and stirring until homogeneous; subsequently adding long-chain molecular compounds and stirring until uniformly mixed to obtain a mixed solution; then transferring the solution to a hydrothermal reactor for hydrothermal treatment; after the reactor cools to room temperature, centrifuging, washing, and drying the hydrothermal product; finally, transferring the hydrothermal product to a high-temperature tube furnace for high-temperature pyrolysis carbonization under an inert atmosphere to obtain the cellulose-based hard carbon anode material. This invention constructs a hard carbon precursor containing a large number of carbonyl groups and nitrogen doping through a hydrolysis competition mechanism, and then prepares the hard carbon anode material through high-temperature pyrolysis carbonization, solving problems such as low reversible capacity, poor first-cycle coulombic efficiency, and performance optimization under extreme high and low temperature conditions in biomass-derived hard carbon.

This invention discloses a method for selectively leaching and separating cobalt, iron, copper, and samarium from samarium-cobalt waste. Utilizing the characteristic that the solubility of samarium sulfate decreases with increasing sulfuric acid concentration and reaction temperature, the samarium-cobalt waste is leached in high-concentration sulfuric acid containing an oxidant at a relatively high reaction temperature. This process leaves most of the samarium in the slag, while cobalt, iron, and copper are leached into the solution through oxidative acid leaching, thus achieving initial separation of cobalt, copper, iron, and samarium. Then, phosphoric acid / phosphate and copper extractants are used to separate iron, copper, and cobalt, respectively. The main components of samarium-rich and samarium-containing slags are Sm₂(SO₄)₃·8H₂O and NaSm(SO₄)₂·H₂O. These are converted to Sm(OH)₃ precipitate using sodium hydroxide, then dissolved in hydrochloric acid, precipitated with oxalic acid, and sintered to prepare high-purity samarium oxide. This invention can effectively separate and recover Co, Ni, Cu, and Sm from samarium-cobalt waste, offering advantages such as high metal recovery rate, high product purity, and environmental friendliness.

The invention relates to a superabsorbent gel, a preparation method and an application of the superabsorbent gel in a cement-based composite material, a cellulose derivative, acrylamide, an additive and a cross-linking agent are mixed to form a reaction system, and the reaction system is subjected to a cross-linking effect under the action of an initiator to obtain the superabsorbent gel. The superabsorbent gel has the advantages of high water absorption rate, low environmental toxicity, high mechanical strength and good dispersity. According to the method, the use of strong oxidizing acid and heavy metal oxidizing agent is obviously reduced, the generation and emission of toxic and harmful waste liquid in the preparation process are reduced from the source, and the development concept of green chemistry is met. The superabsorbent gel prepared by taking carboxymethyl cellulose as a framework is applied to a cement-based composite material, so that the superabsorbent gel can be subjected to efficient electrostatic interaction and coordination bonding with cations such as Ca < 2 + > in cement hydration products through carboxyl, microcracks are more effectively bridged, stress is transferred, and the stability of the cement-based composite material is improved. Therefore, the crack resistance, toughness and durability of the cement-based composite material are further improved from the microscopic level.

The application relates to the technical field of battery materials, in particular to a hard carbon negative electrode material, a preparation method thereof and a sodium ion battery. The preparation method comprises the following steps: starch, cellulose and resin are mixed to obtain mixed raw materials; an oxidizing acid is added into the mixed raw materials, and oxidation crosslinking treatment is carried out at 50-200 DEG C to obtain oxidation-crosslinking materials; the oxidation-crosslinking materials are washed to obtain washed materials; the washed materials are granulated to obtain spherical precursors; the spherical precursors are subjected to low-temperature carbonization in an inert atmosphere to obtain low-temperature pretreated precursors; and the low-temperature pretreated precursors are subjected to carbonization at 1200-1600 DEG C in an inert atmosphere to obtain the hard carbon negative electrode material. The hard carbon negative electrode material is prepared by taking starch, cellulose and resin as the mixed raw materials, combining the pretreatment process of oxidation crosslinking and low-temperature carbonization, the prepared hard carbon negative electrode material has rich closed pore structures and is mainly located on the surface, and the capacity can be improved.