51results about How to "Reduce leaching" patented technology

The invention discloses a method for recycling lithium in a lithium battery, and belongs to the field of lithium battery recycling. The method comprises the following steps: decomposing the lithium battery, and performing pyrolysis treatment at 200-500 DEG C to obtain a slag material; the slag charge is placed in a composite leaching agent, the pH is adjusted to 1.5-2.5, lithium in the slag charge is leached out, and a leaching solution is obtained; the composite leaching agent comprises oxalic acid, an amino acid ligand, persulfate and fluorine ions; adjusting the pH value of the leaching solution to 5.5-6.2, adding an extracting agent into the leaching solution, extracting lithium ions in the leaching solution, and separating to obtain a lithium-rich organic phase and lithium-containing waste liquid; the extraction agent comprises crown ether and organophosphate; and the lithium-rich organic phase is subjected to back extraction, so that lithium ions are released from the organic phase, a lithium-rich back extraction solution is obtained, a carbonate solution is added into the lithium-rich back extraction solution, and lithium carbonate precipitates are obtained. According to the method for recycling the lithium in the lithium battery, selective leaching of the lithium can be achieved, and the comprehensive yield of the lithium in the lithium battery is increased.

The invention discloses a process for repairing damaged soil ecology by lincomycin waste liquid fertilizer, and relates to the technical field of soil remediation, which comprises the following specific steps: step 1, screening and culturing microbial decomposition flora, the invention has the following advantages: through the chelation of the polyaspartic acid derivative on metal ions and the promotion effect on nutrient absorption, the release and transmission of nutrients are precisely regulated and controlled, so that crops can absorb and utilize the nutrients more efficiently; the nano composite material and the specific biological stimulant containing various beneficial microbial strains and natural plant extracts are jointly fused into the liquid fertilizer, the microbial strains in the specific biological stimulant activate the soil biological environment, the natural plant extracts assist plant growth to resist diseases, and the nano composite material and the natural plant extracts have a synergistic effect, so that the liquid fertilizer has a good application prospect. Physicochemical properties and biological activity of soil are optimized, excellent soil micro-ecology is created for plant growth, healthy and strong growth of plants is promoted, and restoration of damaged soil is enhanced.

The invention belongs to the technical field of adhesives, and discloses a low-precipitation chip-scale bottom filling adhesive with excellent bonding performance and a preparation method, the filling adhesive comprises the following components by weight: 2-4 parts of self-synthesized organosiloxane, 30-35 parts of epoxy resin, 1-3 parts of a coupling agent, 1-2 parts of black paste, 60-65 parts of a filler, and 10-15 parts of a curing agent. Compared with the conventional chip-level underfill adhesive, the product provided by the invention has higher bonding strength on a silicon wafer and an LMC substrate; and after being placed in a Uhast environment box for 192 hours, the adhesive still has excellent bonding strength on silicon wafers and LMC substrates under a high-temperature condition. In addition, the product also has the characteristics of excellent flowing property, low precipitation and good heat resistance, and can fully meet the requirements of operability and high reliability of chip integrated packaging.

The invention provides an iron catalytic material as well as a preparation method and application thereof. The method comprises the following steps: carrying out in-situ etching on an iron substrate by adopting an iron salt solution with the concentration of 20-80 mM so as to form an oxygen-containing iron layer containing gamma-FeOOH on the surface of the iron substrate, thereby obtaining the gamma-FeOOH / Fe iron catalytic material, or after the gamma-FeOOH / Fe iron catalytic material is obtained, the gamma-FeOOH / Fe iron catalytic material is calcined at the temperature of 300-500 DEG C in the inert atmosphere, so that gamma-FeOOH in the gamma-FeOOH / Fe iron catalytic material is converted into alpha-Fe2O3, an oxygen-containing iron layer containing alpha-Fe2O3 is formed on the iron base material, and the alpha-Fe2O3 / Fe iron catalytic material is obtained. The gamma-FeOOH / Fe and the alpha-Fe2O3 / Fe can serve as cathode materials to be used for electrochemically activating persulfate to degrade pollutants, metal active sites are effectively fixed and protected through the oxygen-containing iron layer on the surface, leaching of iron ions on a cathode is reduced, and therefore the service life of the cathode is prolonged.

The invention belongs to the technical field of waste recovery, and particularly discloses a retired solar cell silver component recovery process, which comprises the following steps of: mechanically disassembling a retired crystalline silicon photovoltaic module to remove a metal aluminum outer frame and a junction box; and carrying out thermal decomposition to remove the EVA packaging adhesive film so as to obtain the crystalline silicon battery piece. Leaching a valuable metal element Ag in the retired crystalline silicon solar cell by using an organic acid system; the high-purity silver powder is recycled through the three steps of chlorination precipitation, ammonia water dissolution and organic reducing agent reduction. The method has the advantages that organic acid leaching and organic reducing agent reduction are adopted in the silver recovery process, the process is simple, operation is easy, and the safety coefficient is high; compared with other recovery methods, leaching of various impurity ions such as Cu and Pb is reduced, the silver recovery rate is high, and the purity is high; organic acid leaching and organic reducing agent reduction are adopted, so that wastewater is reduced, and environmental pollution is avoided.

The invention relates to the technical field of fertilizer preparation, and particularly discloses a modified flotation phosphate tailing-based composite calcium magnesium phosphate fertilizer and a preparation method thereof, and the composite calcium magnesium phosphate fertilizer is prepared from modified flotation phosphate tailings, dolomite, limestone, an activator, a binder, a magnesium supplement conditioner and water. The flotation phosphate tailings are deeply modified by adopting a composite pretreatment liquid synergistic activation-gradient composite modification process, so that the effectiveness of nutrients such as phosphorus, calcium and magnesium in the flotation phosphate tailings and the environmental safety are remarkably improved; and through the raw material compounding design of calcium and magnesium source collaboration, gradient magnesium supplementation and conditioning synergism, quick-acting and long-acting collaborative supply of nutrients and a soil improvement function are realized. The flotation phosphate tailings are used as main raw materials, the technological process is simple, energy consumption is low, the prepared composite calcium magnesium phosphate fertilizer is balanced in nutrient, lasting in fertilizer efficiency and excellent in physical performance, and unification of solid waste recycling, product high value and production greenization is achieved.

This invention discloses a slow-release fertilizer suitable for lateritic soils in Hainan, comprising a fertilizer core and a coating layer; the fertilizer core comprises the following raw materials in parts by weight: 10-20 parts isobutylene diurea, 1-3 parts 3,4-dimethyl-1H-pyrazole dihydrogen phosphate, 1-3 parts dicyandiamide DCD, 20-30 parts humic acid, and 30-50 parts organic fertilizer; the coating layer comprises the following raw materials in parts by weight: 5-10 parts natural nanotube halloysite, 3-5 parts bentonite, 5-10 parts cyclodextrin, 1-3 parts polyglutamic acid, 1-3 parts wood vinegar, and 5-10 parts polyacrylamide. The isobutylene diurea, humic acid, and organic fertilizer of this invention can effectively replenish organic matter and nitrogen in iron-aluminate soil, maintain soil nitrogen levels, and effectively control the conversion of ammonium nitrogen to nitrate nitrogen in lateritic soil, thereby reducing nitrogen loss and achieving a stable supply of nitrogen. In addition, polyglutamic acid and polyacrylamide have strong water retention capacity, and the fertilizer core is coated with a coating layer to achieve slow release and water retention.

The invention relates to a method for reducing nitrogen loss in a biogas slurry returning and utilization process. The method comprises the following steps: providing biochar; mixing the biochar with kitchen biogas slurry, and mixing and stirring under a constant temperature condition to obtain a biochar biogas slurry mixture; the charcoal and biogas slurry mixture is mixed with soil, so that the nitrogen loss can be reduced. According to the method, kitchen biogas slurry generated by anaerobic fermentation of kitchen waste and biochar are mixed and returned to the field, so that the use cost of wood vinegar is reduced, and the influence of biogas slurry coupled straw returning to the field on crops is avoided. The biochar can fix nitrogen nutrients in the biogas slurry through adsorption, slow release and immobilization effects of the biochar; nitrification can be inhibited, conversion of ammonia nitrogen to nitrate nitrogen is delayed, nitrate is promoted to be reduced into ammonia, and nitrate nitrogen is converted into ammonia nitrogen to be reserved; in addition, the biochar provides a habitat for nitrogen circulating microorganisms, nitrogen turnover of the farmland is accelerated, and therefore nitrogen loss caused by returning of the biogas slurry to the field is reduced.

The invention belongs to the technical field of tobacco detection, and particularly discloses a method for detecting nicotine content in tobacco leaves. The method comprises the following steps: S1, drying and crushing the tobacco leaves, adding a methanol solution of sodium hydroxide for extraction, and centrifuging and filtering through a membrane to obtain a nicotine extracting solution; s2, the nicotine extracting solution is detected through a liquid chromatograph, during detection, mobile phases comprise a mobile phase A containing 90% by volume of water and 10% by volume of methyl alcohol and a mobile phase B containing 90% by volume of methyl alcohol and 10% by volume of water, constant-speed elution is carried out, alkaloid components are determined through comparison with the peak appearance time of a standard substance, and then the concentration of each alkaloid component is calculated according to a standard curve. Sodium hydroxide is combined with acidic groups in nicotine to form soluble salts so as to achieve the purpose of separating and extracting nicotine, and the accuracy of nicotine content determination by liquid chromatography is improved by using an ultraviolet detection method.

This invention discloses a method for preparing and applying chitosan-encapsulated CoCe layered double hydroxide CoCe-LDH. This material can achieve rapid and efficient degradation of roxarsone and removal of the resulting inorganic arsenic. In this material, LDH is encapsulated by chitosan, resulting in a sheet-like material. Chitosan can disperse active sites and adsorb and enrich PMS, while LDH can transfer PMS ions into the anion layer through anion exchange, thereby increasing the active sites. After coupling with the material, PMS is specifically converted to... 1 O2 accelerates the degradation rate.

The application relates to a binder applied to mine slag adhesion, which comprises the following components: 65-70 parts of mine slag, 8-12 parts of calcium aluminate cement, 3-5 parts of mine powder, 2-3 parts of phosphorus powder, 1.5-2.5 parts of water glass, 0.8-1.2 parts of sodium hydroxide, 0.6-0.8 parts of a retarder, and 2-5 parts of an alkaline additive; the alkaline additive comprises modified calcium hydroxide, sodium silicate and sodium carbonate; the modified calcium hydroxide comprises calcium hydroxide and sodium polyphosphate. The application has the effects of improving the cement solidification and adhesion performance, reducing heavy metal ion seepage, and improving the utilization rate of mine slag.

The invention discloses an ecological revetment maintenance agent based on reed residues, a preparation method and application, and belongs to the technical field of revetment construction. The curing agent is prepared from the following components in parts by weight: 40 to 50 parts of reed extracting solution, 1 to 2 parts of fertilizer, 8 to 20 parts of polyaspartic acid, 0.1 to 0.3 part of calcium chloride, 0.2 to 0.5 part of sodium silicate and 1 to 3 parts of water. Uniformly mixing the reed extracting solution with a fertilizer and polyaspartic acid to obtain a premix; dissolving calcium chloride and sodium silicate in water, uniformly mixing, pouring into the premix, and uniformly stirring to obtain a mixture; and compressing the mixture into particles by adopting a granulating machine to obtain the ecological bank protection curing agent. The ecological bank protection curing agent prepared by the invention not only has the characteristics of reducing the nitrogen leaching loss of bank slope soil, increasing soil nutrients, promoting plant growth and the like, but also is rich in raw material source, green, pollution-free, simple to operate, low in cost and capable of realizing resource utilization of organisms.

Relating to the technical field of solid waste resource utilization, the invention discloses a waste incineration fly ash cold bonding aggregate granulation device, which comprises a shell assembly, a center driving and liquid distribution system, a feeding and diversion system, a supergravity reaction rotor, an edge granulation mechanism, a bottom maintenance discharge system and a gas phase and sensing system. Fly ash materials are conveyed and smashed through the feeding and guiding system, then supergravity carbonization and chelating spraying treatment are carried out through the center driving and liquid distributing system, the supergravity reaction rotor and the gas phase system, after fly ash slurry is formed, extrusion compact forming is carried out through the edge granulation mechanism, and the fly ash slurry is obtained. And the formed cold bonding aggregate is cured by the bottom curing and discharging system and then is discharged from the star-shaped discharging valve. According to the method, efficient chemical reaction under a high gravity field and high-strength physical extrusion forming are organically combined, the problems that in the prior art, the carbonization rate is low, the aggregate strength is low and the leaching risk is high are solved, and the high-density and low-leaching fly ash based road aggregate is continuously prepared through a one-step method.

The present invention discloses a method for repairing soil contaminated by electrolytic manganese slag by inoculating white rot fungi, comprising the following steps: mixing biomass and soil contaminated by electrolytic manganese slag to obtain compost raw materials; inoculating white rot fungi in the compost raw materials to obtain a pile; composting and fermenting the pile to obtain compost mature material, thereby completing the repair of soil contaminated by electrolytic manganese slag. The present invention effectively reduces the leaching amount of heavy metal manganese by inoculating white rot fungi, effectively reduces the mobility and bioavailability of heavy metal manganese, effectively changes the structure of microbial communities, increases the number and diversity of microorganisms, improves the seed germination index, and realizes the repair of soil in contaminated sites. It has the advantages of quickly starting composting repair, effectively reducing the leaching amount of heavy metal manganese, reducing the mobility and bioavailability of heavy metal manganese, increasing microbial diversity and community abundance, and improving the seed germination index.

The invention discloses a material for synchronously solidifying and stabilizing granular and effective arsenic and antimony in heavy metal contaminated soil as well as a preparation method and application of the material. The material comprises the following components in percentage by mass: 5-25% of polyacrylamide, 5-20% of nano silicon dioxide, 10-25% of fly ash, 20-60% of ferrihydrite and 5-20% of biochar. The material can efficiently improve the mechanical property of heavy metal contaminated soil and prevent water and soil loss, the granular arsenic / antimony solidification effect is 95% or above, the 28d unconfined compressive strength can be improved by 30-110%, and meanwhile the leaching rate of effective arsenic / antimony is reduced by 99% or above. The material is suitable for repairing arsenic / antimony combined polluted soil, improves the soil stability, and prevents heavy metals from diffusing to the surrounding through surface runoff and soil flow. The material is an environment-friendly material, does not cause damage and large disturbance to soil, and can also improve the soil and maintain the utilization value of the soil while solidifying and stabilizing arsenic / antimony.

The invention discloses a plant underground propagule excitant, and belongs to the technical field of excitant preparation. The plant underground propagule excitant is composed of 169.91-196.13 parts of a mixture A and 2-4 parts of an immobilized microbial agent, and the mixture A is composed of the following components in parts by weight: 0.1-0.2 part of brassinolide, 1-2 parts of sodium nitroprusside, 30-40 parts of cane sugar, 70-80 parts of urea, 68-73 parts of disodium hydrogen phosphate and 0.81-0.93 part of a composite bioactive matter. According to the plant underground propagule excitant prepared by the method, the grassland improvement effect exceeds the expectation, the aboveground biomass is increased by 1-2.5 times, the root biomass is increased by 2-3 times, and the density of vegetation plants (clusters) is increased by 2-3 times.

The invention discloses a carbon-cured red mud-regenerated micro-powder core-shell type ceramsite adsorbent as well as a preparation method and application of the carbon-cured red mud-regenerated micro-powder core-shell type ceramsite adsorbent. The adsorbent comprises the following components in parts by weight: 60-100 parts of sludge biochar, 30-60 parts of red mud, 50-80 parts of regenerated micro powder, 10-20 parts of water, 2-5 parts of a pore forming agent, 0-5 parts of an activating agent and 1-3 parts of a chelating agent, the preparation method comprises the following steps: B1, mixing the red mud, the regenerated micro powder and the pore-forming agent, adding the sludge biochar, and continuously and uniformly mixing; b2, dissolving an activating agent and a chelating agent; b3, spraying the solution, granulating, and screening to obtain ceramsite raw pellets with the particle size of 5-10mm; b4, performing carbon maintenance on the ceramsite raw pellets for 1 day; and B5, placing the cured particles in water, and curing for 3-28 days to obtain the carbon cured red mud-regenerated micro powder core-shell type ceramsite adsorbent. The ceramsite has the characteristics of low carbon, light weight and high adsorption, meanwhile, wastes are effectively utilized, and the environmental pollution is reduced.

The application discloses a method for inhibiting leaching of impurity aluminum ions in ionic rare earth ore, and belongs to the technical field of rare earth ore mining. S1, according to the rare earth content in the ore body, a leaching agent is configured; S2, a buffer is added to the step S1 to configure a composite leaching agent; S3, the composite leaching agent in the step S2 is added to the ore body for leaching; S4, the buffer in the step S2 is configured into a buffer solution with the same pH buffering capacity as the composite leaching agent; S5, after the composite leaching agent in the step S2 is added completely, the buffer solution in the step S4 is continuously added to the ore body until the leaching is completed; the composite leaching agent containing a specific buffer is configured, the pH value of the leaching solution in the leaching process is stably controlled within the range from 4.8 to 5.4; under the pH condition, aluminum ions can form aluminum hydroxide precipitate colloid and are adsorbed in the ore body, while rare earth ions can still stably exist in the leaching solution, so that in-situ separation of the rare earth and the aluminum ions in the leaching stage is realized.

The invention relates to an environment-friendly concrete admixture capable of recycling industrial waste residues and a preparation method of the environment-friendly concrete admixture. According to the method, the household garbage incineration slag is modified firstly, so that the strength of the household garbage incineration slag can be remarkably improved, the porosity and the like of the household garbage incineration slag can be remarkably reduced, and leaching and the like of heavy metal ions of the household garbage incineration slag can be reduced; the environment-friendly concrete admixture which is excellent in performance and capable of recycling the industrial waste residues can be prepared. According to the environment-friendly concrete admixture, the synergistic and complementary effects of different types of smelting slag and raw materials are fully exerted, and the shrinkage resistance and the like of the composite admixture from the early stage to the later stage are achieved.

The invention discloses an Ir-based intermetallic compound electrocatalyst and a preparation method and application thereof, the catalyst comprises a carrier and an intermetallic compound loaded on the carrier, the chemical formula of the intermetallic compound is IrMo (1-x) Cex, x = 0.1-0.3, the preparation method comprises the following steps: (1) uniformly mixing an iridium salt solution, a molybdenum salt solution and a cerium salt, adding water and carbon black, uniformly mixing to obtain a metal salt precursor mixed solution, and drying the mixed solution to obtain metal salt precursor loaded carbon black; and (2) performing Joule heating treatment on the precursor-loaded carbon black in an argon environment, taking out, washing and drying after the Joule heating treatment is finished, thereby obtaining a final product. The Ce element is introduced, so that the electronic structures of Ir and Mo are obviously optimized, the electro-catalytic hydrogen evolution reaction activity is enhanced, and a huge energy application prospect is shown.

The invention discloses a cobalt ferrite modified mesoporous silicon catalyst and a preparation method and application thereof.The preparation method comprises the steps that alkyl quaternary ammonium salt, absolute ethyl alcohol, ammonia water and a silicon source are added into water, stirred and then left to stand; separating and cleaning the white precipitate to obtain a mesoporous silicon material containing a template agent; and putting the mesoporous silicon material containing the template agent and cobalt ferrite into a mortar, fully grinding, and calcining to obtain the cobalt ferrite modified mesoporous silicon catalyst. As the mesoporous silicon material has the characteristics of large specific surface area and highly ordered mesoporous structure, the cobalt ferrite particles can be effectively dispersed, and the problems that the cobalt ferrite particles are easy to agglomerate, low in persulfate activation performance and the like are solved. The cobalt ferrite modified meso-porous silicon catalyst is synthesized through a grinding-calcining one-step method, the method has the advantages that a meso-porous silicon template agent is removed and cobalt ferrite is dispersed and fixed on meso-porous silicon at the same time, the energy consumption is reduced, the cost is saved, and the material synthesis period is shortened; the mesoporous silicon catalyst disclosed by the invention is applied to removal of sulfonamide antibiotics in a water environment.

The invention relates to the technical field of materials, in particular to a tailing treatment method and application of a novel polymer curing agent, and a copolymer composite material has good water resistance, aging resistance and mechanical property. The curing speed is high, and the curing time can be shortened to be within 24 hours under proper conditions; the curing strength is high, and the compressive strength of a cured tailing sample is remarkably improved; and the permeability resistance is good, permeation of water in the tailings is effectively reduced, and leaching of harmful substances is reduced. The paint is environment-friendly, low in VOC (volatile organic compound) emission, biodegradable and pollution-free to the environment.

The invention relates to a novel cobalt-based carbon bead material and a preparation method thereof, the material is a multi-stage ordered pore structure framework loaded multi-form cobalt metal coexisting carbon bead material composed of cage-shaped mesopores and spongy micropores, and the material is formed by co-calcining a graphene oxide doped high-molecular polymer and a metal organic framework structure material, persulfate in water can be efficiently activated, and organic pollutants can be oxidized and degraded. And by regulating and controlling valence state distribution of internal cobalt metal, free radicals are efficiently utilized to accelerate oxidative degradation reaction. The material has the advantages of being easy to recycle, free of metal leaching and wide in application scene.

This invention discloses a pH-responsive slow-release calcium fertilizer compatible with potassium dihydrogen phosphate and its preparation method, belonging to the field of agricultural fertilizer technology. Each liter of the slow-release calcium fertilizer comprises the following components: 1000-1200 g of calcium nitrate tetrahydrate; 50-100 g of small peptide amino acid solution, wherein the free amino acid content in the small peptide amino acid solution is not less than 100 g / kg, and the small peptide amino acid content is not less than 330 g / kg; 60-100 g of erythritol; 3-10 g of sodium alginate; 10-50 g of citric acid; 10-40 g of mannitol; appropriate amount of triethanolamine for adjusting the pH value to 4.5-5.8; and water to a final volume of 1 L. This invention also provides a method for preparing the calcium fertilizer. This calcium fertilizer, through a unique synergistic stabilizing system of erythritol-small peptide-weak acid, not only can be mixed with potassium dihydrogen phosphate without precipitation, solving the problem of calcium-phosphorus antagonism, but also possesses pH-responsive release characteristics, intelligently releasing calcium ions in the acidic environment of plant rhizosphere, significantly improving calcium absorption and utilization.

The application provides a preparation method for improving the gel performance of sturgeon myofibrillar protein, and belongs to the technical field of food processing.The preparation method for improving the gel performance of sturgeon myofibrillar protein provided by the application comprises the following steps: extracting myofibrillar protein in sturgeon meat to obtain a sturgeon myofibrillar protein solution; performing ultrasonic treatment and malondialdehyde induction treatment on the sturgeon myofibrillar protein solution to obtain a composite myofibrillar protein; performing dialysis on the composite myofibrillar protein to obtain a modified protein solution; and performing heat induction on the modified protein solution to obtain sturgeon myofibrillar protein gel.The preparation method can effectively improve the water retention and energy storage modulus of the sturgeon myofibrillar protein gel, so that the water retention capacity and deformation resistance of the gel are significantly enhanced, and the application of the sturgeon myofibrillar protein in gel-based products has an important role.

The application relates to a Bacillus subtilis strain and an application thereof. The strain (Bacillus subtilis) XY01 is preserved in the China Center for Type Culture Collection on September 5, 2022, and the preservation number is CCTCC M20221379. The Bacillus subtilis XY01 degrades grass plants, is used for manufacturing straw pulp by a biological method, and is used for preparing humic acid by using straw pulp black liquor, realizes resource utilization of agricultural solid waste resources such as straw stalks, the black liquor generated in the pulping process is used for field application, and the production chain does not cause environmental pollution. The Bacillus subtilis is mild in the decomposition condition in the biological manufacturing of straw pulp, short in the production cycle, and friendly to the environment.

This invention provides a highly efficient method for treating red mud using a combined acid-base method, relating to the field of comprehensive utilization of red mud. The method uses industrial byproducts hydrochloric acid and sodium hydroxide as leaching agents. Through a step-by-step process—red mud pretreatment, acid leaching for silicon removal, ammonia production and silicon fertilizer preparation, iron powder reduction for titanium extraction and neutralization of the acid leaching solution with ammonia, alkaline leaching for iron and aluminum separation, and the harmless recycling of red mud—it achieves precise separation and recovery of valuable metals such as titanium, iron, and aluminum from red mud. Simultaneously, it completes the production of silicon fertilizer from silicon tailings, the closed-loop recycling of alkaline resources, and the harmless treatment of red mud. This invention solves the technical problems of low resource recovery efficiency, high equipment costs, severe secondary pollution, and high carbon emissions associated with traditional red mud treatment processes. It achieves the resource utilization of all components of red mud, with no wastewater or waste residue discharge. The iron concentrate grade is ≥65%, the titanium concentrate grade is ≥95%, and the sodium aluminate solution can be reused in aluminum plant production lines. The reagent consumption cost per ton of red mud is reduced to below 40 yuan, making it valuable for large-scale industrial application.

The application discloses a ferrous sulfide composite catalyst and a preparation method thereof. The ferrous sulfide composite catalyst comprises a nitrogen-doped carbon layer, and ferrous sulfide nanoparticles are loaded on the nitrogen-doped carbon layer. The preparation method comprises the following steps: mixing iron chloride and ethanol, adding thiourea and o-phenanthroline, stirring, obtaining a precursor dispersion, mixing with melamine, stirring, drying, and obtaining a precursor powder; and calcining the precursor powder, acid washing, and obtaining the ferrous sulfide composite catalyst. The ferrous sulfide composite catalyst has the advantages of excellent catalytic activity, strong stability and the like, can effectively activate an oxidant, a system constructed by the ferrous sulfide composite catalyst can quickly generate a large amount of active species, is favorable for quickly and completely degrading refractory organic pollutants in wastewater, and has high use value and good application prospect. The preparation method also has the advantages of simple process, convenient operation, low cost and the like, and can realize large-scale production and be favorable for industrial application.

The present invention relates to a LaOCl-ZnO composite catalyst, a LaOCl-ZnO hydrogel, and a preparation method and application thereof. The preparation method of the LaOCl-ZnO composite catalyst comprises: calcining lanthanum chloride in an air atmosphere to obtain LaOCl; mixing LaOCl and zinc nitrate uniformly under ultrasonic conditions with water to obtain a mixed solution, adjusting the pH of the mixed solution to 11-13 with a sodium hydroxide solution and reacting under stirring conditions, and then standing, centrifuging, washing and drying to obtain the LaOCl-ZnO composite catalyst. The LaOCl-ZnO composite catalyst prepared by the present invention has a strong photocatalytic redox ability, and the composite structure increases the visible light catalytic activity. The LaOCl-ZnO composite catalyst has great application prospects in photocatalytic treatment of radionuclides.

The invention provides a high-performance pressure-resistant stable arsenic-iron-based alloy and a preparation method thereof.The preparation method comprises the steps that S1, a mixture is provided, and the mixture comprises arsenic-iron powder and chromium powder; the arsenic-iron powder comprises arsenic powder and iron powder; the mass percent of the chromium powder and the arsenic iron powder is not less than 4%; s2, ball-milling the mixture under the protection of inert atmosphere to obtain a ball-milled product; and S3, carrying out vacuum hot pressed sintering on the ball-milled product. On the basis of improving the compressive strength, the leaching toxicity of the arsenic-iron-based alloy can be reduced; compared with an arsenic-iron-based alloy formed by doping cobalt into arsenic-iron powder, the arsenic-iron-based alloy has the advantages that resource utilization of chromium can be achieved, the compressive strength can be further improved, and the problem of leaching toxicity which is not thoroughly solved by cobalt-doped powder is solved; and the leaching of iron can be reduced, and the problem of chromium leaching cannot be caused.