1736 results about "Pregnant leach solution" patented technology

The invention discloses a low-permeability sandstone type uranium mine single-well injection and production method, and belongs to the technical field of in-situ leaching uranium mining. The method comprises the steps that an injection and production well is drilled from the ground to a uranium mine layer; pumping liquid carbon dioxide into the uranium ore layer and soaking; a leaching agent is injected into the uranium ore layer in stages, and soaking is carried out every time the leaching agent is injected; extracting the leachate until the uranium concentration in the leachate is reduced by 10% compared with the initial concentration or the uranium concentration in the leachate is reduced to the preset concentration; carbon dioxide and a leaching agent are supplemented into tail liquid formed after uranium recovery is conducted on the leachate, the tail liquid reaches a saturated state, and the tail liquid in the saturated state is reinjected into the uranium ore layer; and a cycle operation step.

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%.

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 relates to the technical field of waste catalyst recovery, and particularly discloses a method for recovering valuable metals from a waste catalyst containing vanadium and molybdenum. Comprising the following steps: S1, heating and roasting the waste catalyst containing vanadium and molybdenum, continuously heating and roasting, and cooling to obtain a roasted material; s2, mixing the roasted material with a sulfuric acid solution A containing oxalic acid, and heating and leaching to obtain a leaching solution A and a residue A; mixing the residue A with a sulfuric acid solution B containing thiourea and ethylenediaminetetraacetic acid, heating, carrying out secondary leaching to obtain a leaching solution B and a residue B, and washing the residue B with an acid solution to obtain a washing solution; combining the leaching solution and the washing solution to obtain a combined solution; s3, adjusting the pH value of the mixed solution to 2.5-3, then adjusting the pH value to 4.5-5, adding a dimethylglyoxime alcohol solution, and heating to obtain a purified solution; uniformly mixing the purified liquid with the extraction liquid to obtain an organic phase containing vanadium and molybdenum; and S4, reverse extraction and product preparation. The ammonium molybdate and the vanadium pentoxide obtained in the invention have high purity, and the recovery rate of vanadium and molybdenum is high.

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 a method for recycling scandium, iron and aluminum from acid leachate through fractional precipitation, and belongs to the field of hydrometallurgy. The method comprises the following steps: adding a reducing agent into an acid leaching solution to obtain a first modified leaching solution; adding a stable complexing agent into the first modified leaching solution to obtain a second modified leaching solution; adding a pH regulator into the second modified leaching solution, and regulating the pH value of the second modified leaching solution to 3.5-4.5 to obtain a coarse scandium product and a scandium precipitation solution; an oxidizing agent is dropwise added into the scandium precipitation solution, and an iron product and an iron precipitation solution are obtained; and adding a pH regulator into the iron precipitation liquid to regulate the pH value of the iron precipitation liquid to be greater than or equal to 6.0, and carrying out ultrasonic enhanced aluminum ion precipitation to obtain an aluminum product and an aluminum precipitation liquid. Selective modification of metal ions is achieved by adding a reducing agent and a complexing agent, scandium is precipitated through pH regulation and control, iron is precipitated through oxidation regulation and control, and finally complexation and precipitation of aluminum are blocked, so that the separation efficiency of scandium, iron and aluminum in the acid leaching solution is improved at the same time.

The invention discloses a method for comprehensively recovering silicon and magnesium based on rotary kiln-electric furnace type ferronickel slag. The method comprises the following steps: carrying out ball milling, leaching and solid-liquid separation on the rotary kiln-electric furnace type ferronickel slag, standing supersaturated silicon in a leaching solution at normal temperature to generate a gel phenomenon, stirring and crushing to obtain a mixed phase of a magnesium sulfate solution and a silica gel block, and separating the gel solution to obtain a magnesium sulfate crude solution and wet crude silica gel; preparing high-purity hydrated magnesium sulfate with the purity of 99.9% from the magnesium sulfate crude liquid through processes of purification, crystallization and the like; the wet coarse silica gel is subjected to further alkali dissolution, gel forming and other processes to produce silica gel with the purity of 99%; the method has the advantages of low energy consumption, high product added value and element recovery rate and convenience in industrialization, and has excellent popularization and application prospects.

The invention discloses a stone coal vanadium extraction method, and belongs to the technical field of stone coal vanadium extraction, and the method comprises the following steps: crushing stone coal vanadium ore, and simultaneously carrying out microwave irradiation to obtain an activated sample; immersing the activated sample and an oxidizing agent solution into an acid solution, heating and reacting to obtain a suspension, and carrying out solid-liquid separation to obtain a leachate; then, vanadium in the leachate is adsorbed and enriched through ion exchange resin containing quaternary ammonium groups, and an enriched vanadium solution is obtained through desorption with alkali liquor; then adjusting the pH value of the enriched vanadium liquid, adding an impurity removal agent, uniformly stirring, standing, and carrying out solid-liquid separation to obtain a purified liquid; finally, a precipitator is added into the purified liquid, solid-liquid separation is carried out after the reaction is completed, and the ammonium polyvanadate product is obtained.The method not only can remarkably reduce energy consumption, but also can effectively improve the purity of ammonium polyvanadate.

The invention relates to a waste photovoltaic panel recycling method which comprises the following steps: crushing a waste photovoltaic panel until the size of the waste photovoltaic panel is 80-160 meshes, and preparing powder; carrying out acid leaching treatment on the powder, and respectively collecting a leaching solution and a solid material; an acid leaching solution adopted in the acid leaching treatment is a mixed acid aqueous solution of hydrochloric acid and sulfuric acid; the pH of the leachate is adjusted to be neutral with an alkaline agent, then the leachate is mixed with metal iron to be subjected to a replacement reaction, and metal copper is prepared; the solid material is mixed with water, hydrofluoric acid and a flotation agent are added into the obtained mixture for flotation treatment, floats and precipitates are collected respectively, the floats comprise silicon powder, the precipitates comprise glass powder, and the flotation agent comprises one or two of hexadecyl potassium hydrogen phosphate and sodium dodecyl sulfate. According to the recycling method, the silicon powder, the glass powder and the metal copper can be comprehensively recycled from the waste photovoltaic panel.

The invention discloses a method for removing impurities and extracting vanadium from calcification roasting vanadium slag leachate, which comprises the following steps: S1, adding water and a leaching agent into calcification roasting vanadium slag clinker, and uniformly mixing to obtain first ore pulp, the leaching agent at least comprising triethanolamine, potassium sodium tartrate and acid liquor; s2, the pH value of the first ore pulp is adjusted to be 1-6, leaching is conducted under the preset leaching condition, and second ore pulp is obtained; and S3, the second ore pulp is filtered, and vanadium-containing leaching liquid and leaching residues are obtained. According to the method, impurity ion magnesium in the solution is complexed with triethanolamine to generate precipitates during leaching, so that the impurity ions are removed, the obtained leaching solution is low in impurity content and can be directly used for subsequent vanadium precipitation, the magnesium precipitates are flocculent, the leaching slag tailings of vanadium are granular, metals such as magnesium can be separated and recycled, and maximization of economic benefits is realized.

The invention relates to the technical field of iron ore tailing resource utilization, in particular to a method for preparing iron oxide yellow by leaching iron ore tailings through an advanced oxidation technology, which comprises the following steps: adding a required amount of iron ore tailing powder into a persulfate solution, stirring to react, adding a reducing agent, boiling, filtering, adding alkali liquor to adjust the pH value, and filtering, thereby obtaining the iron oxide yellow. Pure liquid containing ferrous ions is obtained; taking part of the pure solution containing ferrous ions, and adding a potassium hydroxide solution to obtain an iron oxide yellow seed crystal solution; adding a pure solution containing ferrous ions into the iron oxide yellow seed crystal solution, adding an alkali solution to adjust the pH value, reacting, and separating and drying a product to obtain the iron oxide yellow. According to the method, the persulfate is adopted to leach iron from the iron ore tailings, and the iron oxide yellow is prepared from the leachate; harmless treatment of the iron ore tailings and value-added utilization of valuable resources are achieved, the raw material source of the iron oxide yellow industry is widened, and a wider prospect is provided for development of iron oxide yellow.

The invention discloses a tritiated waste ash purification method and system based on cooperation of multistage adsorption and low-temperature distillation. The method comprises the following steps: S1, sorting treatment; s2, acid leaching treatment; the waste ash to be treated is subjected to acid leaching treatment, and acid leaching slurry is obtained; s3, carrying out separation treatment; carrying out separation treatment on the acid leaching slurry to obtain acid leaching residues and leachate; s4, adsorption treatment; carrying out adsorption treatment on the leachate to obtain penetrating liquid; s5, catalytic treatment; performing catalytic treatment on the penetrating liquid to obtain tritiated water and catalytic treatment tail gas; and S6, carrying out adsorption treatment on the catalytic treatment tail gas. According to the tritiated waste ash purification method, multi-stage adsorption and low-temperature distillation cooperative treatment is adopted, and the tritiated waste ash purification efficiency is greatly improved. According to the tritiated waste ash purification system, pretreatment, adsorption-catalysis and rectification concentration unit independent packaging are achieved through modular design, and rapid disassembly and assembly and multi-line parallel treatment are supported.

The invention relates to a method for extracting tungsten and molybdenum from low-grade tungsten-molybdenum ore, belongs to the technical field of non-ferrous metal hydrometallurgy, and solves the problems of harsh conditions, low extraction efficiency, high cost and environmental pollution when tungsten and molybdenum are extracted from low-grade tungsten-molybdenum ore in the prior art. The method comprises the following steps: leaching the low-grade tungsten-molybdenum ore by adopting sulfuric acid, and carrying out solid-liquid separation to obtain a leaching solution and leaching residues; extracting molybdenum from the leachate by adopting a cationic extraction agent to obtain tungsten-containing molybdenum extraction raffinate and a negative molybdenum organic phase; and extracting tungsten from the tungsten-containing molybdenum extraction raffinate by adopting a neutral extraction agent to obtain tungsten extraction raffinate and a negative tungsten organic phase. The method is carried out at normal temperature and normal pressure, the complexing characteristic of molybdenum to tungsten in the low-grade tungsten-molybdenum mixed ore under the acidic condition is ingeniously utilized, synergistic leaching of tungsten and molybdenum is achieved, the tungsten and molybdenum extraction efficiency is high, operation is easy and convenient, complexing agents such as phosphoric acid do not need to be added, and the leaching cost is greatly reduced; and the method is clean and environment-friendly, and development and utilization of low-grade tungsten-molybdenum ore are promoted.

The invention discloses a method for recovering nearly all elements in low-precious-metal zinc replacement powder, which belongs to the technical field of non-ferrous metal wet smelting, and comprises the following steps: preparing zinc replacement powder, oxidizing and leaching, extracting copper, preparing cuprous chloride, electrodepositing zinc in raffinate, extracting precious metal by using a gold extracting agent, extracting, reducing and smelting to prepare a gold ingot and a silver ingot, and dissolving by using sodium hydroxide. Preparing lead carbonate; carrying out oxidation acid leaching; replacing; and smelting bismuth. According to the technology for achieving recovery and high-value utilization of nearly all elements in the zinc replacement powder under the mild condition, the technology can be carried out at the normal temperature, the high-pressure condition does not need to be provided, the zinc replacement powder is leached through the acid solution, then various valuable metals are selectively extracted from the leaching solution, corresponding downstream products are prepared, and the method is suitable for industrial production. The method realizes value maximization, does not generate secondary pollution, does not introduce fluorine, has low requirements on equipment, is simple in process and easy to operate, and makes up for the defects of the zinc replacement powder treatment process in the prior art.

The invention belongs to the field of mineral treatment, and particularly relates to a method for selectively leaching niobium from niobium-titanium rare earth bulk concentrate, which comprises the following steps: leaching the niobium-titanium rare earth bulk concentrate by using a buffer solution dissolved with phosphoric acid-sodium phosphate as a leaching agent to obtain a niobium leaching solution and leaching residues enriched with titanium-rare earth; wherein the temperature in the leaching stage is 120-190 DEG C. According to the method, the buffer solution of phosphoric acid-sodium phosphate is innovatively adopted as the leaching agent, and combined control over the leaching temperature is further matched, so that the surface physicochemical characteristics of the niobium-titanium-rare earth bulk concentrate can be adapted, and selective leaching of niobium and separation of titanium-rare earth are achieved.

A process for recovering materials from a black mass material obtained from lithium-ion batteries can include: i) conveying a black mass material as a black mass solid stream; ii) leaching the black mass solid stream to form a pregnant leach solution and residual solids; iii) separating the pregnant leach solution from the residual solids; iv) isolating a copper product from the pregnant leach solution; v) isolating an aluminum (Al) and / or iron (Fe) product from the pregnant leach solution; vi) isolating a manganese (Mn) product from the from the pregnant leach solution; vii) isolating a cobalt (Co) product from the from the pregnant leach solution; viii) isolating a nickel (Ni) product from the from the pregnant leach solution; ix) isolating a salt by-product from the pregnant leach solution; and x) isolating a lithium product the pregnant leach solution.

The invention provides a metal material recycling device and a method for leaching fluorine beryllium thallium and lithium rubidium cesium in lithium slag. Relates to the field of metal material recycling, and comprises a leaching tank placed on the ground through four supporting frames, the top of the leaching tank is fixedly provided with a top cover, and the bottom of the leaching tank is fixedly provided with a bottom cover. According to the metal material recycling device and the leaching method for fluorine beryllium thallium and lithium rubidium cesium in the lithium slag, the ultrasonic generator is arranged to supply energy to the first ultrasonic transducer and the second ultrasonic transducer to generate ultrasonic waves, the ultrasonic waves generate microjet flow to impact the surface of minerals, acid liquor permeation and ion diffusion are accelerated, the leaching time is shortened, and the efficiency is improved; the surface of the lithium slag is not prone to passivation, the leaching rate of target metal ions is increased, the leaching liquid is pumped out through the water suction pump, manual contact with the leaching liquid in the next solid-liquid separation procedure is facilitated, dilute sulfuric acid is supplemented through the acid supplementing pipe, then the lithium slag is placed through the funnel, and the consistency and controllability of starting of the leaching reaction are guaranteed.

The invention aims to provide a device and method for extracting iron from red mud and preparing iron oxide red, and belongs to the technical field of resource utilization, hydrochloric acid is adopted to leach iron element in the red mud, and a ferric chloride solution is separated from leachate through an extraction process. And then, carrying out alkali precipitation, washing and firing to prepare the high-purity iron oxide red. By using the method disclosed by the invention, the iron resource in the red mud can be recycled, so that the dual purposes of resource utilization and environment-friendly treatment are achieved.

The invention belongs to the technical field of dangerous solid waste resource recovery in the nonferrous smelting industry, and discloses a method for recovering arsenic trioxide by leaching arsenic sulfide slag from ferrihydrite. The arsenic sulfide slag is leached by ferrihydrite in an acid solution under the normal pressure condition, so that the leaching rate of arsenic in the arsenic sulfide slag is increased; and sulfur dioxide gas is introduced into the leachate to reduce arsenic in the solution, finally arsenic trioxide is obtained through evaporation concentration and cooling crystallization, meanwhile, oxygen is introduced into the crystallized liquid to oxidize and recycle iron, and cyclic utilization of resources is achieved. The method has the characteristics of simplicity and convenience in operation, low cost, safety, reliability and the like, the arsenic sulfide slag can be effectively recycled to prepare the arsenic trioxide product, and the purpose of treating waste with waste is achieved.

The invention relates to the technical field of lithium recovery, and in particular to a comprehensive utilization process of low-grade clay-type lithium resources, comprising the following steps: S1. grinding raw ore into fine particles, and then sequentially performing constant temperature roasting, constant temperature acid leaching, filtering and washing to obtain leaching residue and leaching solution; S2. adding ammonium sulfate to the leaching solution, filtering to obtain a crude ammonium aluminum sulfate product and a crystallization tail liquid; S3. adding new acid and water to the crystallization tail liquid, and then using it for constant temperature acid leaching again; S4. repeating steps S1-S3 for many times to obtain a lithium-rich crystallization tail liquid; S5. concentrating the lithium-rich crystallization tail liquid, adding NaOH to remove impurities, and then evaporating and concentrating, cooling, crystallizing and filtering to obtain sodium sulfate crystals; S6. precipitating lithium carbonate on the lithium-rich crystallization tail liquid; the aluminum in the leaching solution of the invention is efficiently separated, and an ammonium aluminum sulfate product is prepared; the lithium resources are effectively enriched, and finally a green and efficient comprehensive utilization process of clay-type lithium ore with almost no tail and no wastewater discharge is realized.

The invention discloses a method for recycling laterite-nickel ore metallurgical slag resources, and belongs to the technical field of hydrometallurgy. The method comprises the following steps: carrying out alkaline leaching treatment on the laterite-nickel ore hydrometallurgical slag to obtain alkaline leaching liquid and alkaline leaching slag; carrying out acid leaching treatment on the alkaline leaching residues to obtain acid leaching liquid and acid leaching residues; mixing the acid leaching residues, a biomass reducing agent and an additive, performing primary ball milling treatment, and performing reduction roasting treatment on an obtained product to obtain a roasted product; and mixing the roasted product with a dispersing agent, carrying out secondary ball milling treatment, and carrying out magnetic separation on the obtained product to obtain iron ore concentrate. According to the method, the biomass is carbonized and activated to obtain the biomass reducing agent with enhanced reducibility, the biomass reducing agent is low in cost and environmentally friendly, the biomass reducing agent and the acid leaching residues are continuously mixed according to a specific proportion, reduction roasting is carried out under a specific atmosphere, and then magnetic separation is carried out; and iron ore concentrate with relatively high purity and yield is obtained.

The present invention provides a method for stepwise recovering lithium and rare earths from rare earth molten salt electrolysis slag, belonging to the technical field of metallurgical waste slag treatment and secondary resource recycling. The method comprises the following steps: (1) reacting the rare earth molten salt electrolysis slag with sulfuric acid for leaching to obtain a lithium-containing solution and a leaching residue; (2) mixing the leaching residue with an additive for low-temperature roasting transformation to obtain a roasting product; (3) performing water leaching on the roasting product to obtain a water leaching residue; (4) performing acid leaching on the water leaching residue and adding a reducing agent to obtain a rare earth leaching solution and a leaching residue; wherein, the additive is an alkali and activated carbon, and the reducing agent is formaldehyde or hydrogen peroxide. The method of the present invention realizes the mineral phase transformation and efficient extraction of lithium and rare earths in the rare earth molten salt electrolysis slag, realizes the separation of lithium and rare earths, and at the same time, fluorine can be recovered, having the advantages of high extraction rates of lithium and rare earths and being green.

The invention belongs to the technical field of hydrometallurgy, and particularly relates to a pretreatment method for improving the leaching rate and the carbon adsorption rate of high-sulfur-arsenic gold ore. Comprising the following steps that the high-sulfur-arsenic gold ore is ground and then prepared into ore pulp; a green oxygen activating agent and hydrogen peroxide are sequentially added into the ore pulp, oxidation pretreatment is conducted on the high-sulfur-arsenic gold ore, ore pulp activating liquid is formed, and the green oxygen activating agent is a mixture of calcium oxide, sodium persulfate and soluble bivalent iron salt; and adding a gold leaching agent into the ore pulp activation solution, adjusting the pH value of the ore pulp to 9-12, carrying out stirring gold leaching treatment, filtering to obtain a leaching solution, and then adding activated carbon to adsorb and extract gold. According to the method, a stronger oxidation environment is provided, meanwhile, the residual concentration of arsenate radicals in the solution is effectively reduced, the leaching rate of gold and the adsorption rate of activated carbon are greatly increased, excellent oxidation performance and environment friendliness are shown, and a more sustainable high-sulfur-arsenic gold ore pretreatment process is provided.

The invention discloses a method for synergistically recycling rare earth-containing coal mine acid wastewater and coal gangue, and relates to the technical field of comprehensive utilization of mineral resources, the method mainly comprises the following steps: S1, arranging a rare earth-rich coal gangue dump leaching field and building a heap; s2, spraying the rare earth-containing coal mine acid wastewater and collecting leachate; s3, separation and enrichment of rare earth elements; and S4, carrying out high-valued treatment on resources such as iron and aluminum in the residual solution. According to the method, valuable resources such as rare earth in the rare-earth-containing coal mine acid wastewater and the rare-earth-rich coal gangue are synergistically recycled, meanwhile, treatment of the coal mine acid wastewater and preparation of the polymeric ferric aluminum sulfate are achieved, the concept of maximum value of comprehensive utilization of resources is achieved, and the treatment process is low in cost and little in environmental pollution.

The invention belongs to the technical field of wastewater treatment, and provides a method for removing and recovering manganese from acid mine wastewater. The method comprises the steps that the acid mine wastewater is subjected to iron removal treatment to obtain iron removal supernate, a manganese removal agent is added into the iron removal supernate to obtain manganese precipitation residues and manganese removal supernate, the manganese precipitation residues and sulfuric acid are mixed to obtain leaching liquid and leaching residues, and the leaching liquid is electrolyzed to obtain metal manganese; the manganese removal agent is sodium silicate and / or sodium metasilicate. According to the method, the added manganese removal agent does not enable silicate ions and manganese ions to generate manganese silicate, but enables the silicate ions to generate a hydrated calcium silicate adsorbent or a porous magnesium silicate adsorbent in situ with calcium and magnesium ions by using the calcium and magnesium ions existing in the acid mine wastewater, so that the recovery and removal of manganese are realized; the method disclosed by the invention is simple and low in cost, and not only realizes recovery of manganese resources, but also realizes deep treatment of residual manganese; and the leaching residues generated in the manganese recovery stage can also be used for deeply treating the manganese-removed supernate, so that the generation of waste residues is reduced.

The invention relates to a method for purifying rhodium from a complex-component rhodium leaching solution, and belongs to the technical field of precious metal refining and purification. The method comprises the following steps: adding a reducing agent into rhodium leaching liquid for reduction to obtain RhCl3 primary purification liquid and insoluble slag; simultaneously adding sulfite and ammonium salt into the RhCl3 primary purification liquid to precipitate rhodium in the form of (NH4) 3Rh (SO3) 3; hydrochloric acid is added into the (NH4) 3Rh (SO3) 3 precipitation residues, heating and boiling are conducted, the (NH4) 3Rh (SO3) 3 precipitation residues are dissolved in the form of RhCl3 and enter a solution, SO3 < 2-> in the solution is removed in the form of SO2, and a secondary purification solution of RhCl3 is obtained; adding a strong oxidant into the secondary purified solution of RhCl3, and carrying out oxidation reaction to obtain RhCl4; adding alkali into the RhCl4 solution to adjust the pH value, and boiling to obtain RhO2. 2H2O precipitation slag; and the RhO2. 2H2O precipitation slag is sequentially subjected to pure water slurrying, hydrazine hydrate reduction, calcination and hydrogen reduction to obtain the high-purity metal rhodium. According to the method disclosed by the invention, the high-purity metal rhodium of which the purity is greater than 99.95% can be prepared, and the direct recovery rate of rhodium is greater than 97%.

The invention discloses a precious metal leaching agent based on thiosulfate and a precious metal leaching process. The leaching agent contains thiosulfate, a thiourea-based catalyst and an iron-based oxidizing agent, and the molar ratio of the thiosulfate to the thiourea-based catalyst to the iron-based oxidizing agent is (0.05-5): (0.005-1): (0.005-1). According to the leaching agent, on the basis of the synergistic effect of all the components, the dissolution efficiency of precious metal is improved, generation of polysulfate in side reaction is greatly reduced, and follow-up precious metal recovery is facilitated. A leaching process adopting the leaching agent comprises the following steps: exposing precious metal sites of a precious metal-containing material, adding the leaching agent, adjusting the pH value of a leaching system, carrying out a leaching reaction, and carrying out solid-liquid separation after the reaction is finished, so as to obtain a precious metal leachate. According to the technology, by controlling the pH value of the system and the adding amount of the leaching agent, leaching of different grades and types of precious metal-containing materials can be achieved under the normal temperature condition, and tests show that by taking gold ore as an example, the gold recovery rate of the technology can reach 100% at most.

The invention discloses a method for recovering rare earth elements from fluorgypsum, which comprises the following steps: 1) crushing fluorgypsum, and mixing with a sulfuric acid aqueous solution to obtain a mixed slurry I; roasting the mixed slurry I to obtain roasted ore; 2) mixing the roasted ore with water to obtain mixed slurry II; leaching the mixed slurry II to obtain a leached product; carrying out solid-liquid separation on the leaching product to obtain a leaching solution and water leaching residues; 3) adding a precipitant into the leachate, and stirring for precipitation reaction to obtain mixed slurry III; carrying out solid-liquid separation on the mixed slurry III to obtain precipitates containing rare earth elements and filtrate I; 4) adding a water treatment agent into the filtrate I, and stirring for reaction to obtain mixed slurry IV; and carrying out solid-liquid separation on the mixed slurry IV to obtain mixed residues and filtrate II. According to the method, the rare earth elements in the fluorgypsum are efficiently recycled.

The invention relates to a method for recycling battery-grade nickel sulfate from nickel-containing industrial waste, and belongs to the technical field of nonferrous metallurgy. The method comprises the steps that the nickel-containing industrial waste is subjected to water leaching treatment, and nickel-containing leachate is obtained; carrying out gradient pH regulation and control on the nickel-containing leaching solution by adopting calcium carbonate to obtain a purified solution; carrying out first countercurrent extraction on the purified liquid by adopting an organic phase I with the D2EHPA concentration of 0.1-0.3 mol / L; carrying out second counter-current extraction on the raffinate I obtained in the step (3) by adopting an organic phase II with the CYANEX 272 concentration of 0.05-0.2 mol / L; the raffinate II obtained in the step (4) is subjected to adsorption and oil removal through activated carbon and then is subjected to evaporative crystallization, and nickel sulfate crystals and crystallization mother liquor are obtained. The method is high in nickel recovery rate, the purity of nickel sulfate is larger than or equal to 99.9%, and the sodium content is low.

The invention belongs to the field of metallurgy, and particularly relates to a method for comprehensively recovering iron, vanadium, titanium, scandium and gallium through cooperation of vanadium titano-magnetite and red mud, which comprises the following steps: a) mixing vanadium titano-magnetite concentrate powder and red mud powder, roasting, leaching in water, and carrying out solid-liquid separation to obtain leached residues and leached liquid; b) mixing the leachate with a precipitant to precipitate vanadium, and carrying out solid-liquid separation to obtain vanadium-rich slag and vanadium-precipitated clear liquid; dissolving the vanadium-rich slag in a sulfuric acid solution, mixing the vanadium-rich slag with ammonium salt to react, carrying out solid-liquid separation, and roasting the obtained solid product ammonium polyvanadate to obtain V2O5; resin is used for adsorbing and desorbing gallium ions in the vanadium precipitation clear liquid, the pH of desorption liquid is adjusted to be alkaline, then electrolysis is conducted, and crude gallium is obtained; c) washing and drying the leaching residues to prepare pellets; after the pellets are pre-reduced, a carbonaceous reducing agent is mixed, melt separation treatment is carried out, and scandium-containing high-titanium slag and molten iron are obtained; and Ti and Sc in the scandium-containing high titanium slag are recycled. The method has the advantages of simple process, cleanness, high efficiency and the like.