545 results about "FERRIC IRON" patented technology

The invention provides a gold leaching agent for treating high-carbon gold-bearing minerals and a gold leaching process, and belongs to the technical field of hydrometallurgy. According to the gold leaching agent, guanidinium thiocyanate is used as an agent main body, a hydroximic acid compound is used as a complexing synergist, and soluble inorganic salt of ferric iron is used as a competitive adsorbent. In a leaching system, guanidine thiocyanate can be decomposed to generate guanidine, sodium sulfide, sodium thiocyanate and water. Thiourea anions are converted into cyanamide under the alkaline condition, then cyanamide is slowly released and decomposed into cyanide ions, the cyanide ions are complexed with gold ions, and gold leaching is achieved. Namely, guanidinium thiocyanate has the effect of releasing the cyanide ions step by step, and slow release of the cyanide ions is realized. The gold leaching agent system does not contain cyanide (sodium cyanide, potassium cyanide and the like) and is a clean and environment-friendly agent system, and efficient leaching of gold in high-carbon gold-bearing minerals can be achieved through the synergistic effect of all functional agent components.

The invention discloses a high-efficiency sulfur-iron-based nitrogen and phosphorus removal and autotrophic denitrification composite filler and a preparation method thereof. The high-efficiency sulfur-iron-based nitrogen and phosphorus removal and autotrophic denitrification composite filler is characterized by comprising the following raw material components in percentage by mass: 1-60% of activated pyrite powder, 30-95% of sulfur, 1-10% of trivalent iron salt and 1-10% of limestone powder. And forming through a thermal compounding process. The preparation method comprises the following specific steps: firstly, activating the pyrite and the magnetic pyrite at high temperature under the protection of protective gas; sulfur is heated to be in a molten state; uniformly mixing the activated pyrite powder, trivalent iron salt and limestone powder to obtain a powdery mixed material; adding the powdery mixed material into molten sulfur, raising the temperature to 125-145 DEG C, and fully and uniformly mixing; and finally, cooling and curing the obtained material to obtain the autotrophic denitrification composite filler. According to the high-efficiency sulfur-iron-based autotrophic denitrification nitrogen and phosphorus removal composite filler prepared by the preparation method, pyrite is calcined and activated, ferric iron salt is used as an oxidizing agent to promote decomposition of the activated pyrite, and the electron donor release capability of the pyrite is improved, so that the high-efficiency nitrogen and phosphorus removal effect of the filler is realized.

The invention discloses an oxidation leaching system and method for argillaceous sandstone uranium ore. The system comprises a uranium leaching pool, a recovery pool, a liquid preparation-dosing unit pool and an intermediate pool. Wherein the uranium leaching tank is provided with a water dispersing layer, a uranium ore layer and a liquid collecting layer from top to bottom, and efficient oxidation of uranium ore is achieved through coupling of oxygen and ferric iron; the recovery pool is sequentially provided with a resin adsorption layer and a water inlet layer from top to bottom, and efficient recovery of uranium in the leachate is achieved; the liquid preparation-dosing unit pool is provided with an acid-resistant submersible sewage pump used for circularly conveying the ore leaching liquid to the uranium leaching pool and adjusting the pH value of the ore leaching liquid and the initial concentration of Fe < 3 + >. And the middle tank drives the ore leaching liquid to form periodic tidal flow circulation in the uranium leaching tank through an acid-resistant submersible sewage pump. According to the system and the method, tidal flow regulation and control, aeration oxygen supply enhancement and iron ion circulation oxidation technologies are coupled, and the uranium leaching rate gt of the argillaceous sandstone uranium ore is achieved by establishing a multi-stage oxidation field domain, optimizing a fluid migration path and establishing an iron element regeneration mechanism; 92%.

The invention relates to the technical field of ozone catalysts, in particular to an iron-manganese bimetallic ozone catalyst as well as a preparation method and application thereof. The iron-manganese bimetallic ozone catalyst comprises an activated carbon carrier and an iron-manganese bimetallic oxide loaded on the activated carbon carrier, in the preparation process of the iron-manganese double-metal ozone oxidizing agent, anhydrous nitrate of ferric iron and divalent manganese is adopted and dissolved in absolute ethyl alcohol, then activated carbon is added for excessive dipping, drying and under-pressure calcination, and the iron-manganese double-metal ozone oxidizing agent can be obtained. When the ferro-manganese bimetallic ozone oxidizing agent is combined with ozone to remove refractory COD (Chemical Oxygen Demand) in advanced sewage treatment, the ferro-manganese bimetallic ozone oxidizing agent shows relatively good catalytic activity, the removal rate of the refractory COD in the advanced sewage treatment can reach 57.9 percent within 60 minutes, and the ferro-manganese bimetallic ozone oxidizing agent has a wide application prospect.

This invention discloses a method for leaching lithium iron phosphate mixed powder with iron salts and recovering all components, belonging to the field of battery recycling. The invention uses an iron salt solution to leach the mixed powder, obtaining a lithium-containing leachate and leaching residue. Ferrous ions in the leachate are regenerated into ferric iron through acidification and oxidation, and recycled for leaching the next batch of mixed powder. After reaching a preset number of cycles, the leachate is used for re-leaching multiple batches of leaching residue to improve the lithium leaching rate. Ultimately, a enriched solution containing Li, Fe, Cu, and Al and graphite-containing iron phosphate residue are obtained. Copper is recovered from the enriched solution through iron powder replacement, and a high-purity lithium chloride solution is obtained through extraction and separation, while ferric chloride (recycled) and aluminum chloride crystals are also recovered. The leaching residue is treated with hydrochloric acid to obtain regenerated graphite, and the pH is adjusted with alkali to obtain high-purity iron phosphate. This method achieves full component recovery under mild conditions, reducing separation steps and chemical consumption through a "leaching-regeneration-leaching" cycle mechanism, thus achieving both environmental and economic benefits.

The invention provides aluminum-doped hematite, a preparation method of the aluminum-doped hematite and application of the aluminum-doped hematite in catalyzing peroxides to degrade organic pollutants or remove pathogenic bacteria. The preparation method of the aluminum-doped hematite comprises the following steps: adding ferric iron salt and aluminum salt into deionized water, reacting, precipitating to separate out a product, washing, drying and grinding to obtain a precursor; calcining the precursor, and then washing and drying to obtain the aluminum-doped hematite. The preparation method is simple, cheap and easily available in raw materials, low in cost, green, safe and environment-friendly; the aluminum element is introduced into the hematite, so that the catalytic activity of the hematite is improved, and the catalytic condition is easy to realize; the aluminum-doped hematite disclosed by the invention has excellent capability of activating peroxide, so that the aluminum-doped hematite shows excellent performance in the aspects of removing environmental organic pollutants and sterilizing.

The invention discloses a recovery method for extracting lithium, copper and aluminum from waste lithium iron phosphate batteries. The method comprises the following steps: firstly, pretreating the lithium iron phosphate waste battery to obtain a sheet-shaped positive and negative pole piece mixture, then leaching the pole piece mixture by taking a ferric iron salt solution as a leaching agent, and filtering to obtain a lithium-containing leachate and ferrophosphorus slag containing copper and aluminum current collectors; and oxidizing the lithium-containing leaching solution, adjusting the pH value, filtering and separating to obtain a lithium-containing purified solution and ferric hydroxide precipitate. Continuously increasing the pH value of the lithium-containing leachate to remove impurities, adding a sodium carbonate saturated solution, and precipitating and crystallizing to obtain lithium carbonate; and dissolving the ferric hydroxide precipitate with dilute acid to prepare a ferric salt solution which is circularly used as a leaching agent. Comprising ferrophosphorus slag of copper and aluminum current collectors, a copper and aluminum current collector mixture and the ferrophosphorus slag are obtained through separation of hydrodynamic screening equipment, the copper and aluminum current collector mixture is dried, ground and then separated through a specific gravity separator, and copper powder and aluminum powder are obtained. According to the method, the technological process is shortened, the project investment and the production cost are relatively low, and the method is suitable for large-scale recycling treatment of the waste lithium iron phosphate batteries.

The present invention relates to the technical field of inorganic materials, and particularly to a method for clean smelting of beryllium oxide and beryllium oxide. The smelting method includes using iron powder to remove trivalent iron in the acid leaching solution of beryllium ore; using a non-saponified extraction system without sodium ions and ammonium cations, and the non-saponified extraction system exchanges hydrogen ions with itself when extracting beryllium ions. The present invention solves the problems existing in beryllium smelting preparation in the prior art, such as low beryllium recovery rate, easy interference by associated elements, large pollution, and difficult waste liquid treatment. An alkaline earth metal compound is used as a raffinate impurity removal reagent and a non-saponified extraction system, and the raffinate after impurity removal is recycled for beryllium ore leaching, improving the beryllium recovery rate and reducing the environmental pollution caused by waste liquid discharge.

The invention provides an improved treatment method for laterite-nickel ore. The improved treatment method comprises the following steps: S1, carrying out acid leaching on the laterite-nickel ore, and then filtering and washing to obtain a leached solution and first leached residues; step S2, the step S2 is selected from any one of a step S2-1, a step S2-2 and a step S2-3; s3, performing first-stage nickel and cobalt precipitation and dense filtration on the aluminum and scandium removed liquid or the iron and aluminum removed liquid by adopting a precipitator to obtain first-stage nickel and cobalt precipitation liquid and a nickel cobalt hydroxide product; and S4, carrying out second-stage nickel-cobalt precipitation on the first-stage nickel-cobalt precipitation solution by adopting a nickel-cobalt precipitation neutralizer and an oxidizing agent to obtain a magnesium sulfate manganese solution and nickel-cobalt-manganese slurry. In the traditional process, ferrous iron is oxidized by using compressed air, so that energy is wasted. According to the method, the manganese-containing substance is adopted as the oxidizing agent, ferrous iron is oxidized into ferric iron, the problems that the ferrous iron is low in oxidation rate under the low pH and compressed air is wasted are solved, and the scandium recovery rate is increased.

The invention relates to an electrochemical cleaning method for removing organic matters on the surface of a silicon carbide wafer, which comprises the following steps of: immersing the silicon carbide wafer with the polluted surface into electrolyte containing bivalent and / or trivalent ferric salt, applying voltage or current between a cathode material and an anode material, and carrying out electrochemical reaction to remove the organic matters on the surface of the silicon carbide wafer. The surface of the silicon carbide wafer is subjected to organic matter removal. According to the method, an electrochemical oxidation method technology is adopted, the strong oxidation effect of hydroxyl free radicals is utilized, organic residues on the surface of the silicon carbide wafer are oxidized and decomposed into short-chain organic matter, water, carbon dioxide and other products, and the purpose of removing the organic residues is achieved. The method provided by the invention is simple and efficient, can quickly remove organic pollutant residues on the surface of the silicon carbide wafer, does not use high-concentration chemicals and organic component cleaning agents which are difficult to degrade in the cleaning process, is safe and reliable to operate, reduces the consumption of the chemicals, avoids secondary pollution, and is more environment-friendly.

The invention discloses a method for directly and selectively extracting indium from a high-iron indium-containing solution without reduction, which comprises the following steps: mixing the high-iron zinc indium-containing solution obtained by acid leaching of zinc oxide with a composite extractant, extracting, separating to obtain an indium-iron-containing organic phase, adding a detergent into the indium-iron-containing organic phase for washing, and separating to obtain a zinc-removed indium-iron-containing organic phase, the method comprises the following steps: adding a composite extractant into a high-iron-zinc indium-containing solution, then adding a stripping agent to carry out indium stripping to obtain an indium-containing stripping solution so as to realize the separation of indium in the high-iron-zinc indium-containing solution, and the composite extractant consists of 10-40% by volume of a phosphate extractant A, 5-20% by volume of a phosphoric acid synergistic extractant B and 40-85% by volume of sulfonated kerosene. According to the method, ferric iron does not need to be reduced, the indium-iron separation coefficient is high, extraction is not prone to emulsification, and the indium recovery rate is high.

The present invention relates to the field of lithium-ion battery positive electrode materials. A preparation method for an iron phosphate material. The method comprises the following steps: mixing an organic phosphorus solution with humic acid, so as to obtain a mixed solution; adding a solution containing ferrate radicals into the mixed solution, so as to obtain a solution containing ferric iron; adjusting the pH of the solution containing ferric iron to generate a precipitate, and filtering same to obtain the precipitate; and drying the precipitate, and removing crystal water, so as to obtain an anhydrous FePO4 material. By using a ferrate to oxidize organic phosphorus, the ferrate itself is reduced into ferric iron, and provides an iron source and also serves as an oxidizing agent; by introducing humic acid during the oxidation process, a competitive oxidation relationship with the organic phosphorus is formed; the ferrate is activated into an iron-based intermediate having higher oxidizability; and after the humic acid is oxidized, the electronegativity is enhanced, such that iron ions can be adsorbed to play a dispersing role, thereby preventing the generated iron phosphate from being agglomerated, such that the particle size thereof is uniform, which is conductive to improving the electrical properties of the subsequently prepared lithium iron phosphate.

The utility model discloses a treatment device capable of accelerating starting of autotrophic denitrification of pyrite, and belongs to the technical field of sewage treatment. The Fe < 3 + > dosing unit comprises a Fe < 3 + > dosing tank (4) and a dosing pump (6); according to the water inlet unit, an aeration head (2) is arranged in a raw water tank (3), the aeration head (2) is connected with a nitrogen cylinder (1) through a valve, filler filled in the reactor is modified pyrite filler particles and modified ceramsite, the bottom of the reactor is connected with an aeration pump, and a Fe < 3 + > dosing tank (4) is connected with a water inlet (7) in the bottom of the reactor (13) through a dosing pump (6). The method comprises the following steps: aerating sludge, standing, discharging water, and adding ferric iron into the water subjected to nitrogen aeration treatment to carry out accelerated reaction. By adopting the technology of the utility model, the starting can be quickly carried out for more than 10 days.

The invention relates to the technical field of wastewater treatment, in particular to a preparation method and application of iron modified montmorillonite. The preparation method comprises the following steps: adding montmorillonite into water, carrying out ultrasonic treatment, and then centrifuging to obtain supernate; centrifuging the supernate, and freeze-drying the obtained precipitate to obtain pretreated montmorillonite; dispersing the pretreated montmorillonite in water, adjusting the pH value of the solution to be acidic, and stirring; then adding ferric iron salt, stirring and centrifuging; dispersing precipitates obtained by centrifugation into a ferric iron salt solution, stirring and centrifuging; repeating the steps of dispersing the precipitate obtained by centrifugation into the ferric iron salt solution, stirring and centrifuging; and washing the precipitate obtained by the last centrifugation, and then freeze-drying to obtain the iron modified montmorillonite. The iron-modified montmorillonite can effectively degrade the triazine herbicide simazine, is simple to prepare, wide in raw material source and low in price, and has important significance in removal of refractory pollutant triazine herbicides.

The invention discloses a resource utilization method of Fenton iron mud. According to the method, a citric acid-ascorbic acid composite solution is used for soaking Fenton iron mud, hydrothermal liquefaction is carried out in an inert reduction system, ferric iron is reduced into ferrous iron, and a ferrous iron solution generated after reaction can directly form a Fenton reagent with hydrogen peroxide to be reused for Fenton reaction. By the adoption of the method, iron can be completely recycled, resource utilization of the Fenton iron mud is facilitated, the mass of the treated filter residues is only 1 / 10 of that of the iron mud, and the disposal amount of hazardous waste is effectively reduced.

The invention belongs to the technical field of battery materials, and mainly relates to a method for preparing an inorganic carbon composite sodium ferric sulfate positive electrode material under the assistance of reduced iron powder and a sodium ion battery. The method comprises the following steps: adding sodium sulfate, ferrous sulfate and reduced iron powder into deionized water, stirring until the sodium sulfate and the ferrous sulfate are completely dissolved, and separating the residual reduced iron powder to obtain a sodium ferric sulfate precursor solution; mixing the sodium ferric sulfate precursor solution with an inorganic carbon source, stirring, and carrying out spray drying to obtain an inorganic carbon composite sodium ferric sulfate positive electrode material precursor; and sintering the precursor in an inert atmosphere to obtain the inorganic carbon composite sodium ferric sulfate positive electrode material. According to the method, ferric iron is reduced into ferrous iron with electrochemical activity by using the reducing iron powder, and the inorganic carbon source is used as the conductive agent, so that the problem of poor conductivity of the material caused by incomplete decomposition of the organic carbon source in the sintering process is avoided, the pure-phase sodium ferric sulfate positive electrode material with high conductivity is synthesized and prepared, and the electrochemical performance of the material is improved.

The invention relates to the technical field of wastewater treatment, and discloses a method for synergistically strengthening denitrification of an anaerobic ammonia oxidation system based on tea polyphenol and ferric iron, and the method comprises the following steps: in an anaerobic ammonia oxidation reactor, inoculating anaerobic ammonia oxidation sludge, adding wastewater, adding tea polyphenol-Fe < 3 + >, and treating the wastewater. According to the invention, the tea polyphenol can promote the anaerobic ammonium oxidation bacteria to absorb ferric iron and enhance the biological utilization of iron element in the anaerobic ammonium oxidation system. Iron elements absorbed by the anaerobic ammonium oxidation bacteria can be used for synthesizing key functional enzymes, the metabolic activity of anaerobic ammonium oxidation and dissimilatory nitrate reduction into ammonium of the anaerobic ammonium oxidation bacteria is enhanced, meanwhile, coupling of two nitrogen conversion ways is promoted, the total nitrogen removal rate is synergistically increased, and the denitrification efficiency of an anaerobic ammonium oxidation system is enhanced.

The invention discloses a method for accelerating straw composting by utilizing magnetite and compound microorganisms to drive biological advanced oxidation, and belongs to the technical field of efficient composting of agricultural organic solid wastes. The method comprises the following steps: (1) uniformly mixing straws and excrement as a compost body, adjusting the C / N ratio and the water content, adding magnetite, a bacillus subtilis liquid and a crushed white rot fungus liquid, and putting the mixture into a composting device; (2) intermittent aeration is carried out, the temperature is 28-32 DEG C, and the composting period is 40-50 days. According to the composting method, through intermittent aeration, controllable aerobic conditions and anoxic conditions are formed in a compost body, under the anoxic conditions, ferric iron is subjected to dissimilatory iron reduction to generate ferrous iron, and under the aerobic conditions, compound microorganisms reduce oxygen through extracellular electron transfer to form hydrogen peroxide, so that the composting effect is improved. Divalent iron and hydrogen peroxide are subjected to a Fenton-like reaction to generate hydroxyl free radicals with high oxidizing property, so that decomposition of straw lignocellulose is accelerated, and the composting efficiency of compost is improved.

The present application relates to the field of photovoltaic glass, and discloses ultra-white float photovoltaic glass and a manufacturing method therefor. The ultra-white float photovoltaic glass of the present application comprises the following components: 71%-73% of SiO2, 0.5%-1.5% of Al2O3, 0.008%-0.012% of Fe2O3, 7.5%-9.5% of CaO, 3.5%-5.0% of MgO, 12.5%-14.0% of Na2O, 0.2%-1.0% of K2O, and 0.2%-0.4% of SO3. According to the present application, by adjusting the composition of the glass and in combination with adjustments of a melting process and a tin bath forming process, the content proportion of ferrous irons in the ultra-white float photovoltaic glass is reduced, the content proportion of ferric irons is increased, and the tin count in the glass is reduced to achieve the purpose of improving the transmittance, flatness and weather resistance of the ultra-white float photovoltaic glass, thereby satisfying the quality requirements of the photovoltaic glass, and the photovoltaic glass can be applied to a photovoltaic module.

The invention belongs to the technical field of nanomaterials, and discloses a nanoflower-shaped FeOOH / NiFe-LDH composite material as well as a preparation method and application of the nanoflower-shaped FeOOH / NiFe-LDH composite material. The preparation method comprises the following steps: taking urea as a pH regulator, uniformly dispersing the urea, soluble nickel salt and soluble ferric iron salt in water, then adding a morphology control agent NH4F, and uniformly mixing to obtain a mixed solution; the mixed solution is subjected to a homogeneous reaction under the stirring condition, and after the reaction is finished, the nanoflower-shaped FeOOH / NiFe-LDH composite material is obtained. The preparation method is low in reaction temperature, short in reaction time and simple, the prepared composite material is of a three-dimensional structure, low in impedance and large in specific surface area, and the multi-phase composite material is multiple in charge transfer paths, high in electron migration rate, high in stability and excellent in electrochemical performance.

The invention belongs to the technical field of wastewater treatment, and discloses a magnetic nano composite adsorbent as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving a divalent iron salt and a trivalent iron salt in water, adding ammonia water under a protective gas, and carrying out a stirring reaction at a rotating speed of 350-600 rpm to prepare Fe3O4 nanoparticles; the preparation method comprises the following steps: dispersing Fe3O4 nanoparticles in a mixed solution of acrylic acid and ethidene diamine, then adding an initiator, and carrying out a stirring reaction at a rotating speed of 150-300 rpm to prepare the magnetic nano composite adsorbent. The magnetic nano-composite adsorbent provided by the invention can efficiently remove lead ions in wastewater, is not influenced by mercury ions and copper ions, also has relatively good adsorption capacity on the mercury ions and the copper ions, and can treat various heavy metal ions in the wastewater at the same time. The magnetic nano composite adsorbent is easy to separate and good in reusability.

The invention discloses a magnetic iron oxide catalyst for wet catalytic oxidation of sludge and a preparation method of the magnetic iron oxide catalyst, and belongs to the field of preparation of catalyst materials. The method specifically comprises the following steps: dissolving a trivalent iron salt and a divalent iron salt in water in proportion to obtain a mixed solution; under the protection atmosphere of inert gas, adding an alkaline solution into the mixed solution, and adjusting the pH value to be 8-12; sequentially washing off impurities by using water and an organic detergent to obtain a reactant; and carrying out vacuum drying on the reactant, and grinding to obtain the magnetic iron oxide catalyst. The catalyst can effectively reduce the content of organic substances in the sludge pyrolysis liquid in the catalytic wet oxidation process, and has good magnetism and recoverability before and after the reaction. After five times of circulation, the catalyst still keeps a stable organic matter removal effect and good magnetism. The method is expected to be applied to the fields of sludge resource utilization, environmental water pollutant removal and the like.

The invention provides a multi-characteristic iron-carbon derivative material for adsorbing and repairing PFAS pollution of a water body as well as a preparation method and application of the multi-characteristic iron-carbon derivative material. The preparation method comprises the following steps: 1, dissolving a ferric salt in N, N-dimethylformamide, adding a ligand terephthalic acid under a stirring condition, and synthesizing a precursor through a solvothermal method; and 2, carrying out heat treatment on the precursor in an inert atmosphere to obtain the multi-characteristic iron-carbon derivative material. The application of the multi-characteristic iron-carbon derivative material in the aspect of environmental restoration comprises the following steps: by taking the multi-characteristic iron-carbon derivative material as an adsorbent, carrying out adsorption purification treatment on a PFAS polluted water body under the assistance of a cationic complexing agent. The multi-characteristic iron-carbon derivative material is synthesized through a solvothermal-thermal treatment two-step method, so that the multi-characteristic iron-carbon derivative material has high hydrophobicity, a two-dimensional-three-dimensional tight interface and magnetism, can quickly remove PFAS with various different structures and carbon chain lengths, can realize material separation within 30 seconds after the PFAS is removed through adsorption, and does not generate secondary pollution.

The present invention discloses a rapid preparation method and application of a NiFe-LDH nickel-based electrode, belonging to the technical fields of electrolytic water hydrogen production and anion exchange membrane electrolytic water. The preparation method includes the following steps: S1. Under normal temperature and pressure, immerse the cleaned nickel-based substrate material into a ferric iron (Fe<supgt;3+< / supgt;) etching solution for chemical etching, let it stand for an appropriate time to fully react, and then take it out and dry; S2. Immerse the material obtained in step S1 into a strong alkaline solution for soaking treatment, let it stand for an appropriate time to fully react, and then take it out and dry; S3. Assemble the electrode material prepared in step S2 into a membrane electrode, and install it into a single cell of an anion exchange membrane electrolytic water tank for testing, so that it can stably convert electrical energy into hydrogen energy during operation. This technical solution can rapidly, low-cost, greenly and in large quantities prepare an electrolytic water anode electrode, overcomes the drawbacks of the cumbersome electrode preparation methods in the current same field, and is expected to promote the commercial development of alkaline membrane electrolytic water hydrogen production technology.

The invention discloses a method for separating and recycling phosphorus, iron and lithium in battery black powder, and relates to the technical field of battery recycling. The method comprises the following steps: carrying out acid leaching on battery black powder to obtain a battery black powder leaching solution and filter residues; an oxidizing agent is added into the battery black powder leaching solution, the pH of the solution is adjusted to 1.8-2.5, solid-liquid separation is conducted after the reaction is completed, and iron phosphate sediment and a lithium-containing solution are obtained; adjusting the pH value of the lithium-containing solution to 10-12, and carrying out solid-liquid separation after the reaction is completed to obtain a metal precipitate and a lithium sulfate solution; dissolving the iron phosphate precipitate in a sulfuric acid solution, adding a reducing agent to reduce ferric iron into ferrous iron, separating out ferrous sulfate by adopting an alcohol precipitation method or an ammonium sulfate crystallization method, and performing solid-liquid separation after the reaction is completed to obtain ferrous sulfate precipitate or ammonium ferrous sulfate crystals and mother liquor; and evaporating and concentrating the mother liquor, and extracting to obtain a phosphoric acid solution. According to the method, the three elements of phosphorus, iron and lithium in the battery black powder can be recycled, and the environmental problem caused by stacking of the lithium extraction slag can be avoided.

The invention discloses a biochar-plant combined remediation method for mine heavy metal contaminated soil, and relates to modified biochar and a remediation accelerator.The preparation method of the modified biochar comprises the steps that peanut shells are subjected to high-temperature carbonization and then added into a ferric iron solution to neutralize a NaOH solution, ultrasonic treatment is conducted, and the biochar is obtained; a biomass raw material is crushed and composted to obtain pretreated biomass, then the pretreated biomass and a ferric iron solution are subjected to a heating reaction, a reaction product is mixed with the biochar, carbonization is continued, and the biochar is obtained. The repairing accelerant comprises turf, phospholime powder, mannitol, a plant growth regulator, a microbial agent and a chelating agent. According to the remediation method, planting of the modified biochar, the remediation accelerant and the enrichment plants is combined, a synergistic remediation mechanism is formed, the three components have a synergistic effect, the removal efficiency of heavy metal is remarkably improved, the biomass and the survival rate of the enrichment plants are improved, and efficient and accurate remediation of the mine heavy metal contaminated soil is achieved.

The invention relates to the technical field of sewage treatment and resource utilization, in particular to a method for recovering phosphorus from sludge, which comprises the following steps: carrying out anaerobic digestion on the sludge to be treated under anaerobic conditions to release phosphorus in the sludge into supernate to obtain sludge anaerobic digestion liquid, adding an iron salt coagulant into the sludge anaerobic digestion liquid, precipitating, filtering, washing and drying to obtain the phosphorus-containing sludge. Removing phosphorus from the supernate, enabling the phosphorus to enter a precipitate, and removing the supernate to obtain a solid-liquid mixture; and adding the solid-liquid mixture into a reactor, adding a mixed bacterial agent of iron reducing bacteria and metal-resistant bacteria into the reactor, reducing ferric iron into ferrous iron under the action of the iron reducing bacteria, dissolving the precipitate, and recrystallizing to obtain the blue iron ore, thereby realizing the recovery of phosphorus in the sludge. According to the invention, ferric salt precipitates are re-induced to precipitate and recrystallize, so that the problems of low phosphorus load, large volume, low economic benefit of direct recovery, low crystallinity of chemical precipitates, more impurities, difficulty in controlling dissolved oxygen and easiness in oxidation at present are solved.

A molecular sieve catalytic slag melting agent for high-iron coal liquid slag removal comprises 10-20 parts of a loosening and expanding agent, 10-20 parts of a molecular sieve catalyst and 30-60 parts of a fluxing reducing agent, and has the beneficial effects that the loosening and expanding agent can crack and expand ash; vanadium anhydride added in the fluxing reducing agent can promote generation of low-temperature eutectic substances in the ash residues when the mass fraction is lower than 5%. And further, under the action of the molecular sieve catalyst enhanced reaction, the fluxing reducing agent can enhance the reducing atmosphere, promote the conversion of ferric iron in the slag body to ferrous iron, reduce the melting point of an iron-containing compound, promote the conversion of the solid slag body at the slag discharge port to low-melting-point liquid-phase flow slag, and ensure that ash in the furnace is smoothly discharged out of the furnace body. Through reasonable preparation, the slag melting agent developed by the invention can realize fluidization of slag at a slag discharge port within a temperature range of 900 DEG C, avoids unplanned furnace shutdown or safety problems caused by slag blockage, and also can realize the effect of replacing the existing natural gas heating fluxing anti-slag-blocking technology.

The invention discloses an organic wastewater advanced treatment method and device with low agent input. The method comprises the following steps: an anaerobic biological iron-sulfur reduction reaction process: fully mixing elemental sulfur, ferric iron, iron-sulfur reduction sludge and wastewater containing organic carbon and organic pollutants with electronegative groups, carrying out anaerobic biological elemental sulfur reduction and iron reduction reactions, and directionally generating polysulfide and ferrous sulfide in situ; a nucleophilic substitution reaction process: carrying out nucleophilic substitution reaction on the organic pollutants with the electronegative groups and the polysulfide, and removing the electronegative groups to generate a reduced organic product; in the oxidation reaction process, ferrous sulfide reacts with dissolved oxygen to generate hydroxyl free radicals, the reduction state organic product is oxidized and degraded, and elemental sulfur and ferric iron are generated; and a sludge precipitation process: refluxing the precipitate to the anaerobic biological iron-sulfur reduction reaction zone, and discharging clarified water. The method provided by the invention realizes deep degradation and detoxification of refractory organic pollutants, and has the advantages of low agent investment, low cost and no secondary pollution.

The invention relates to the technical field of preparation of battery materials, and discloses a method for synthesizing iron phosphate through continuous oxidation, which comprises the following steps: oxidation: oxidizing a ferrous solution by adopting oxygen-containing gas to obtain a ferric iron solution; synthesizing iron phosphate: reacting the ferric iron solution with a phosphorus source to obtain amorphous iron phosphate; and crystal transformation and roasting: carrying out crystal transformation and roasting on the amorphous iron phosphate to obtain the iron phosphate. The iron phosphate material prepared by the invention is oxidized by adopting the oxygen-containing gas, so that compared with hydrogen peroxide adopted in the prior art, the cost is lower, and the specific surface area and the tap density of the prepared iron phosphate material are higher.