190 results about "Ferric hydroxide" patented technology

The invention discloses a chlorobenzene wastewater continuous stripping purification recovery device and an implementation method, the chlorobenzene wastewater continuous stripping purification recovery device comprises an aeration tank, an alkali water washing system, an acid water washing system, an acid-base neutralization system and a ferric hydroxide separation system, the aeration tank is connected with the alkali water washing system, the acid water washing system is connected with the alkali water washing system, and the acid water washing system is connected with the ferric hydroxide separation system. The acid-base neutralization system is connected with the alkali-water washing system, the acid-water washing system and the ferric hydroxide separation system, and the alkali-water washing system and the acid-water washing system are both in two-stage steam stripping, and have the following advantages: alkali washing water and acid washing water generated in the chlorobenzene production process are subjected to two-stage nitrogen steam stripping, so that the content of organic matters is greatly reduced; ferric hydroxide is generated through neutralization of acid-alkali wastewater, the total amount of the wastewater is reduced, then the ferric hydroxide reacts with hydrochloric acid in the pickling water to generate ferric trichloride, hydrochloric acid is neutralized, the neutralization product ferric hydroxide is consumed, the wastewater amount is reduced, and recycling of wastewater resources is achieved.

The invention provides a low-cyanide gold leaching agent system and a dump leaching process thereof, and belongs to the technical field of hydrometallurgy. According to the method, a synergistic process of'interface activation, cyanide etching and iron precipitation inhibition 'is constructed by designing a low-cyanide gold leaching agent system. The amino acid auxiliary leaching agent adsorbs the gold surface to weaken lattice energy, so that the etching efficiency of trace cyanide ions is improved; mercapto-containing malic acid is used as a chelating agent, specific mercapto in molecules of the mercapto-containing malic acid and iron ions form an ultrahigh-stability water-soluble complex, generation of ferric hydroxide precipitates is thoroughly blocked, ferrous ions stabilized by the chelating agent are subjected to in-situ oxidation through dissolved oxygen and efficiently regenerated into potassium ferricyanide, and accumulation of free cyanogens in a solution system is eliminated; meanwhile, a chelating agent-iron complex forms a self-buffering pair, the pH of the dump leaching solution is accurately controlled, and secondary precipitation caused by local alkalization is prevented. According to the process, under the synergistic effect that the core chelating agent guarantees permeation stability and the leaching aid accelerates gold dissolution, the heap leaching period is compressed to 45 days.

The invention discloses a recycling method of NF3 residual electrolysis liquid, and relates to the technical field of residual electrolysis liquid recycling treatment. The method comprises the following steps: step 1, removing Fe ions in the electrolytic residual liquid: firstly, adding hydrogen peroxide or oxygen into the electrolytic residual liquid for reaction, oxidizing ferrous ions into ferric ions, then adding ammonia water and sodium hydroxide or ammonium bicarbonate and sodium hydroxide into the solution for reaction, precipitating ferric ions in the form of ferric hydroxide; 2, hydrofluoric acid is added into the electrolyte solution obtained after iron removal to adjust the pH of filtrate to 3-12, the filtrate enters an extraction system, the nickel element in ammonium hydrogen fluoride is extracted out, and ammonium hydrogen fluoride is purified; and step 3, the nickel element separated from the electrolyte enters a second section to be extracted and synthesized into a nickel sulfate product.

The invention provides a collaborative treatment and resource utilization process for CO2 in industrial solid waste and tail gas, and belongs to the technical field of environmental protection. According to the method, carbon residues in the gasified slag are used as a catalyst, and aluminum and silicon are extracted through the gasified slag chemical method under the polybasic acid aqua regia effect and the electrochemical effect. According to the method disclosed by the invention, a stack retting neutralization mode is adopted, so that the superacid and aluminum and iron oxides in the ash residues are converted into soluble salts, and ferric hydroxide, aluminum hydroxide and polybasic acid ammonium are sequentially replaced from a salt solution by virtue of an ammonia replacement method, so that the use safety risk of high oxidability of polybasic acid is overcome; rapid crystallization of the aluminum salt solution in the form of aluminum chloride is promoted by using the same ion effect; performing stack retting neutralization reaction on the slag charge and sodium hydroxide to generate sodium silicate, introducing carbon dioxide to obtain silicic acid and sodium carbonate, and reacting the sodium carbonate solution with calcium hydroxide to obtain sodium hydroxide. The sodium hydroxide, the polyatomic acid, the ammonia gas and the activated carbon are recycled for treating the fly ash and the coal gangue, so that the comprehensive utilization of multi-element solid waste is realized.

The invention discloses a method for deeply removing arsenic from a nickel sulfate solution, which comprises the following steps: adjusting the pH value by using nickel hydroxide to form colloid to preliminarily remove arsenic, oxidizing by using sodium sulfate, and adding polyferric sulfate to form ferric hydroxide colloid to deeply adsorb and remove arsenic, and is simple in process, convenient to implement in the production process, capable of greatly reducing the cost and reducing the environmental pollution, and suitable for industrial production. The method comprises the following steps: adjusting the pH value of a low-pH leaching solution / anolyte / crude nickel sulfate dissolving solution to 4.0 or more by using nickel hydroxide, carrying out filter pressing to remove slag, adding arsenic ions in a sodium persulfate oxidation solution, reacting for 30 minutes, adding polyferric sulfate, reacting for 30 minutes, and carrying out filter pressing to obtain a nickel sulfate solution which is almost free of arsenic, and the method is efficient, safe and environment-friendly.

A method and equipment for recycling alumina red mud. First, the alumina red mud is added to a mixed acid of hydrochloric acid and sulfuric acid for reaction to dissolve metals such as iron, aluminum, calcium, sodium, and a small amount of zinc, copper, magnesium, etc., and the solid silicon dioxide is left to be separated as building materials or glass raw materials; after the solution is collected, ammonium bicarbonate is added to obtain aluminum, calcium, and some metal precipitates and separated. Iron and sodium remain in the solution and continue to react with sodium hydroxide to obtain iron hydroxide precipitate and separate out sodium salts. After evaporation of the concentrated solution, iron oxide is obtained as a raw material for steel production; the aluminum, calcium, and other metal precipitates are added to sulfuric acid with a concentration of 90-98% for reaction. After all are dissolved, the solution is subjected to membrane separation and then carbonates are added to obtain calcium carbonate precipitate as a raw material for cement production; after evaporation of the concentrated solution, high-purity alumina is obtained and sent to an aluminum processing plant to produce pure aluminum or aluminum alloy products; the separated sodium salt solution is evaporated to be used as industrial and agricultural salt; the acid mist and harmful gases in the reactor process are treated by an absorption tower and then discharged. The present invention can make full use of the iron oxide, alumina, and effective components of alumina red mud, solves the problem of environmental pollution caused by the large amount of piled-up alumina red mud at present, has a low cost, and is suitable for the current alumina production plants.

The invention relates to a low-cobalt-salt adhesion promoter and a preparation method thereof, and relates to the technical field of rubber adhesives, the low-cobalt-salt adhesion promoter is of a core-shell structure and comprises, by mass, 10-15 parts of core metal precursor powder, 15-20 parts of a shell SiO2 shell layer and 5-8 parts of long-chain alkylsilane grafted to the surface of the SiO2 shell layer; the metal precursor powder comprises cobalt hydroxide, manganese hydroxide and ferric hydroxide, and the molar ratio of the cobalt hydroxide to the manganese hydroxide to the ferric hydroxide is 1: (2-3): (1-1.5). According to the invention, the dispersibility of the low-cobalt salt adhesion promoter and the compatibility with rubber can be effectively improved.

The invention discloses a comprehensive utilization method of refining slag, which comprises the following steps: dissolving the refining slag in hydrochloric acid to obtain a refining slag pickle liquor; filtering the refining slag pickle liquor to obtain first filtrate and filter residues, and washing the filter residues to obtain first solid and first washing liquor; combining the first washing liquid and the first filtrate to obtain a second mixed solution; and adding an oxidizing agent into the second mixed solution to obtain a first precipitate. According to the method, the refining slag is subjected to acid leaching with hydrochloric acid, the PH value of the solution is adjusted, silicon dioxide, aluminum hydroxide, ferric hydroxide, calcium chloride or calcium oxide and recycled hydrochloric acid are obtained, the accumulated refining slag is decomposed into various new substances in the process reaction, the method is simple, the substance purity is high, the refining slag is recycled, and large economic value can be created; and meanwhile, mining of various resources is reduced. And a new direction is found for comprehensive utilization of the refining slag.

The invention relates to the technical field of battery materials, and discloses a lithium-sulfur battery catalyst, a preparation method thereof and a lithium-sulfur battery. According to the lithium-sulfur battery catalyst, particles of the catalyst comprise an MXTiO base material and alpha-Fe2O3 deposited on the surface of the MXTiO base material; the MXTiO base material comprises an MXene nanosheet and a titanium oxide layer covering the surface of the MXene nanosheet; the metal element in the MXene nanosheet is Ti. The preparation method comprises the following steps: carrying out hydrothermal reaction on MXene to generate titanium oxide on the surface of MXene to obtain an MXTiO material; preparing a mixed dispersion liquid, wherein iron ions are dissolved in the mixed dispersion liquid, and an MXTiO material is dispersed in the mixed dispersion liquid; alkali liquor is added into the mixed dispersion liquid, ferric hydroxide is precipitated on the surfaces of particles of the MXTiO material, then a reaction product is calcined, and the MXTiO / alpha-Fe2O3 heterostructure material is obtained. The catalyst shows excellent electro-catalytic performance in the lithium-sulfur battery.

The invention discloses a clean, efficient and low-cost lithium extraction slag utilization method which comprises the following steps: mixing lithium extraction slag with a fluxing agent, and sequentially carrying out roasting treatment, solid-liquid separation treatment, aging treatment and water leaching treatment to obtain a second solid-liquid mixture; carrying out solid-liquid separation treatment on the second solid-liquid mixture to obtain a second filter residue and a second filtrate; performing carbon separation method treatment on the first filtrate to obtain a third solid-liquid mixture; carrying out solid-liquid separation treatment on the third solid-liquid mixture to obtain a third filter residue and a third filtrate; the main component of the second filter residue and the third filter residue is white carbon black; performing heat treatment on the second filtrate and the third filtrate to obtain a fourth solid-liquid mixture; performing solid-liquid separation treatment on the fourth solid-liquid mixture to obtain fourth filter residues and fourth filtrate; the main components of the fourth filter residue are aluminum hydroxide and ferric hydroxide; and separating the fourth filtrate to obtain a sodium sulfate crystal substance and a potassium sulfate crystal substance.

The application provides a clean recycling method of waste lithium iron phosphate positive electrode material, which comprises the following steps: (1) the waste lithium iron phosphate positive electrode material is pretreated to separate aluminum foil, a binder and carbon, and a mixture containing phosphorus, iron and lithium is obtained; (2) the mixture is subjected to oxidative leaching in a sodium hydroxide solution, and the obtained mixed slurry is subjected to solid-liquid separation to obtain iron hydroxide precipitation and a leaching solution; (3) sodium carbonate and the leaching solution are mixed, lithium is precipitated, and solid-liquid separation is performed to obtain lithium carbonate and a separation solution; the separation solution is subjected to crystallization and solid-liquid separation to obtain sodium phosphate crystals; (4) the lithium carbonate in step (2), the iron hydroxide precipitation in step (3), phosphoric acid and carbon powder are mixed, and calcination is performed to obtain lithium iron phosphate. The clean recycling method can realize high-purity and high-efficiency recycling of the waste lithium iron phosphate positive electrode material, and the process flow is clean and environmentally friendly.

The invention provides continuous wastewater treatment equipment, which belongs to the technical field of wastewater treatment, and comprises a treatment tank and an observation window arranged in the middle of the treatment tank, and further comprises a multi-stage treatment assembly, a pollution discharge purification assembly and a stripping assembly, deep purification of the wastewater is realized through multi-stage treatment; the vertical spraying is combined with the stirring of the fan blades and the scrapers, strong water flow scouring force is formed above the elastic filter plate, meanwhile, the convex plates periodically extrude the elastic filter plate during rotation to enable the elastic filter plate to vibrate, suspended particles and impurities can be effectively prevented from being accumulated on the surface of the elastic filter plate, the risk of filter plate blockage is reduced, and meanwhile, the service life of the filter plate is prolonged. Ferric hydroxide colloid generated by ferrite reaction can more uniformly adsorb suspended particles under the driving of upper and lower water flows, and the precipitation separation of the suspended particles is accelerated; the connecting shaft rotates to drive the mounting cylinder, the arc-shaped groove of the trigger cavity is matched with the ball, the oxidation disc vibrates, the vibration strength is adjusted according to the descending amplitude of the oxidation disc, and the overall wastewater treatment efficiency is improved.

The invention discloses a treatment method of an electrolyte after wet crushing of a waste lithium ion battery. During crushing, an alkaline solution is sprayed out of a spraying opening located above a shearing opening to completely cover the waste lithium ion battery crushed material, a hydrolysis reaction is carried out under the cooperation of ultrasonic waves, and waste water, a pole piece mixture, a shell pile head, a diaphragm and the like are separated out through hydrodynamic force. The method comprises the following steps: adding dilute acid into wastewater to adjust the pH value, adding bivalent iron salt and hydrogen peroxide, performing Fenton oxidation and mineralization on an organic solvent in the wastewater under the synergism of ultrasonic waves, then adding an alkali metal salt solution to adjust the pH value, and filtering and separating to obtain filtrate and ferric hydroxide precipitate; adding alkali into the filtrate twice to adjust the pH value for precipitation, and filtering to separate valuable precipitate and filtrate; and adding dilute acid into the ferric hydroxide precipitate for dissolving, and then adding a reducing agent to obtain a ferrous salt solution which is circularly used for Fenton reaction. According to the method, hydrolysis, Fenton oxygenolysis, mineralization of the organic electrolyte and regeneration and recycling of the ferrous salt are adopted, and the method is suitable for large-scale and low-cost treatment of the electrolyte in the waste lithium ion battery.

The invention belongs to the technical field of high-iron bauxite resource utilization, and discloses a method for removing iron in high-iron bauxite, which comprises the following steps: mixing and stirring high-iron bauxite, an iron removal agent and water to obtain mixed ore pulp; wherein the iron removal agent is a mixture of oxalic acid and oxalate; stirring and leaching the mixed ore pulp so as to carry out iron removal reaction; after the iron removal reaction is finished, liquid-solid separation is carried out, and leaching residues and leaching liquid are obtained; adjusting the pH value of the leachate, and stirring to carry out a reaction of precipitating iron and aluminum; after the precipitation reaction is finished, carrying out liquid-solid separation to obtain filter residues and filtrate containing oxalate; carrying out an aluminum removal reaction on the filter residue by using an aluminum removal agent, and after the aluminum removal reaction is finished, carrying out liquid-solid separation to obtain a ferric hydroxide precipitate and a sodium aluminate solution; according to the method, aluminum and iron in the aluminum-iron embedded structure in the high-iron bauxite are removed through wet preimpregnation, the adverse effect of iron oxide on aluminum mineral dissolution is eliminated, and the dissolution rate of the aluminum mineral is increased.

The invention relates to a method for recycling valuable resources from a waste lithium iron phosphate material, and belongs to the technical field of recycling of waste lithium iron phosphate batteries. The method comprises the following steps: dispersing a waste lithium iron phosphate material in water to obtain a mixture I; respectively adding an acid solution and an oxidant solution into the mixture I at the same time to carry out leaching reaction, and carrying out solid-liquid separation to obtain a leaching solution A and active ferrophosphorus slag; iron powder and the leachate A are subjected to a replacement reaction to recover copper in the leachate A, and copper sponge and lithium-rich leachate are obtained; and calcining the active ferrophosphorus slag for crystal transformation to obtain decarbonized ferrophosphorus slag, the decarburized ferrophosphorus slag is mixed with alkali liquor, the mixture is placed in a mill to be subjected to ball-milling leaching, and leachate B and ferric hydroxide are obtained; and adjusting the pH value of the leachate B to be alkaline to obtain an aluminum hydroxide and phosphate solution. The method provided by the invention is simple to operate and low in cost, has good economic benefits and is easy for industrial application.

The utility model belongs to the technical field of chemical equipment, and discloses an iron and boron removal device in magnesium chloride production, which comprises a dissolving kettle, an impurity removal kettle, a heat preservation sedimentation kettle, a first filtering device, an acid adjusting kettle, an iron and boron removal kettle, a second filtering device, a concentration kettle, a crystallization kettle, a centrifugal machine, a drying machine and a packaging machine which are sequentially communicated through pipelines, adjusting valves and pumps, the dissolving kettle is provided with a magnesium chloride crude product feeding hole and a water feeding hole; a liquid material outlet of the first filtering device is communicated to a feeding hole of the acid adjusting kettle, the iron and boron removing kettle is provided with a hydrogen peroxide feeding hole and a ferric hydroxide feeding hole, and a liquid material outlet of the second filtering device is communicated to a feeding hole of the concentration kettle; and a liquid material outlet of the centrifugal machine is communicated with a water feeding hole of the dissolving kettle through a pipeline. According to the device, iron and boron elements in the magnesium chloride crude product are removed, the treatment effect is good, the purity of the obtained product is high, and the application range is wide.

The present invention relates to the technical field of soil remediation, and particularly relates to a stabilizer for contaminated soil remediation and a preparation method thereof. The stabilizer includes: modified neutralization residue a and modified neutralization residue b; the preparation method of the modified neutralization residue a includes: mixing a first part of the neutralization residue with water to obtain a suspension, reacting the suspension at 80-140 °C and a pH value of 10-12, stirring and mixing the reaction product liquid with diatomite, and after solid-liquid separation, obtaining the modified neutralization residue a; the preparation method of the modified neutralization residue b includes: mixing a second part of the neutralization residue with an alkaline material and then calcining to obtain the modified neutralization residue b; in the neutralization residue, the mass content of calcium oxide is 27%-30%, the mass content of calcium sulfate is 34%-38%, and the mass content of iron hydroxide is 16%-20%. When the stabilizer is used to treat contaminated soil, the reduction rate of the leaching concentration of lead and cadmium in the contaminated soil is greater than 80%.

The invention provides a titanium recovery and all-component recycling cooperative treatment method in sulfate process titanium dioxide waste acid. The method comprises the following steps: diffusion dialysis separation, sulfuric acid concentration, metal separation, titanium component recycling, iron and manganese precipitation and precipitation waste liquid treatment. According to the titanium recovery and all-component recycling co-processing method in the sulfate process titanium dioxide waste acid, most free sulfuric acid and impurity ions in the sulfate process titanium dioxide waste acid are removed firstly through the core steps of diffusion dialysis and extraction and / or adsorption, so that a subsequent extraction / adsorption system is converted into a low-acid and low-impurity environment from a high-acid and high-impurity environment, and the titanium recovery and all-component recycling co-processing method in the sulfate process titanium dioxide waste acid is realized. According to the method, the recovery rate of titanium is increased from less than 1% to more than 80%, the efficient recovery of titanium is realized, the recovery of sulfuric acid is realized, high-purity ferric hydroxide and manganese hydroxide products (the recovery rates are both greater than 70%) are produced, and the efficient recycling of waste acid is really realized.

The application provides a method for preparing a magnetic heterostructure material of magnetite-graphene and application of the magnetic heterostructure material in a directional heat-conducting composite material, and belongs to the technical field of composite materials. The method comprises the following steps: (1) slowly adding a sodium hydroxide solution into a ferric chloride solution under water bath condition to prepare a ferric hydroxide gel, and sequentially performing drying and aging, centrifugation, cleaning and freeze drying on the gel to obtain a ferrous oxide nanocrystal; (2) adding the ferrous oxide nanocrystal, graphene and dopamine hydrochloride into a Tris buffer solution and fully stirring, and performing multiple centrifugation, cleaning and freeze drying to obtain ferrous oxide-dopamine-graphene; and (3) performing calcination reduction on the ferrous oxide-dopamine-graphene to obtain the magnetic heterostructure material of magnetite-graphene. The magnetic heterostructure material prepared by the method can be applied to the preparation of the directional heat-conducting composite material as a heat-conducting filler, and has the advantages of high operability, low cost and the like.

The invention discloses a method for recovering iron resources from jarosite, which comprises the following steps: S1, reacting ammonium oxalate with jarosite to realize jarosite phase dissolution: mixing jarosite with ammonium oxalate, and heating and reacting in a water reaction system to generate ammonia gas to obtain leached residues and leached liquid; s2, the leachate reacts with ammonia to precipitate and separate iron, and ammonium oxalate is recycled: S2.1, the leachate reacts with the ammonia: ammonia gas is introduced into the leachate or ammonia water is added into the leachate for full reaction, and reaction product slurry containing ferric hydroxide precipitate and ammonium oxalate is obtained; and S2.2, separating ferric hydroxide and ammonium oxalate from the reaction product slurry: filtering and separating to obtain a ferric hydroxide precipitate, and cooling to separate out crystals from ammonium oxalate in the filtrate so as to recover ammonium oxalate. According to the method, ammonium oxalate used for replacing iron in the iron vitriol can be recycled, the raw material cost is low, iron element separation and utilization are achieved, solid waste is remarkably reduced, and enrichment of other valuable elements in the iron vitriol is facilitated.

The utility model discloses a device for reducing manganese loss through segmented leaching, and belongs to the technical field of manganese purification. The utility model discloses a device for reducing manganese loss through segmented leaching. The device comprises a first reaction mechanism, a first filter press, a second reaction mechanism, a second filter press, a third reaction mechanism, a third filter press and a leachate tank which are sequentially connected in series, the first filter press, the second filter press and the third filter press are respectively used for receiving products discharged by the first reaction mechanism, the second reaction mechanism and the third reaction mechanism and separating to obtain leaching residues and leaching liquid, and the first-section leaching residues separated by the first filter press in the first reaction mechanism are calcium sulfate and SiO2; the first-section leachate is conveyed to the second reaction mechanism by the first filter press; the second-section leaching residue separated by the second filter press in the second reaction mechanism is ferric hydroxide, and the second-section leaching liquid is conveyed to a third reaction mechanism by the second filter press; and the leaching liquid output by the third filter press is manganese-rich liquid and is conveyed to the leaching liquid tank.

The invention discloses a precipitation-loaded slow-release carbon-based iron fertilizer and a preparation method thereof. The preparation method specifically comprises the following steps: firstly, a biological crustacean heavy metal adsorbent is immersed in a calcium hydroxide solution, dried, and then immersed in a ferrous sulfate solution twice, and finally dried and granulated. The slow-release iron fertilizer is loaded by precipitation, and a precipitated ferric hydroxide, ferrous hydroxide mixture and excess ferric sulfate are uniformly dispersed and attached to the inside of pores of a porous adsorbent. Excess ferric sulfate can quickly provide iron ions to antagonize cadmium and arsenic ion absorption in the early growth stage of rice. Calcium sulfate encapsulates the precipitated ferric hydroxide and ferrous hydroxide in the porous adsorbent, which can achieve long-term slow-release of iron ions and reduce soil oxygen content. Iron ion antagonism is performed throughout the entire rice growth process. The precipitation-type adsorption loading method greatly increases the release cycle of the iron ions. The iron fertilizer of the invention has an excellent cadmium and arsenic antagonistic effect on rice and has excellent application prospects.

The invention discloses a method for determining the content of cadmium in edible salt through a coprecipitation atomic absorption graphite furnace method, and belongs to the technical field of trace detection. According to the characteristic that cadmium ions can generate cadmium hydroxide under an alkaline condition, ferric nitrate is used as a coprecipitator, the pH value is adjusted to 9.0 by using ammonia water, the generated cadmium hydroxide and ferric hydroxide are co-precipitated, a supernatant is removed, the precipitate is acidified, an atomic absorption spectrophotometer graphite furnace method is used for determination, and a result shows that the adding standard recovery rate of a sample is 104%; and the relative standard deviation is 2.4%. And the relative standard deviation between the ICP-MS determination result and the determination result of the method is 0.03%, which indicates that the interference of the method is not obvious. According to the method, the interference of sodium chloride in the sample is eliminated, the cadmium element in the sample can be enriched, and the cadmium content in the test sample is increased, so that the detection lower limit of the determination of the cadmium content in the edible salt is reduced, and the determination accuracy and precision are improved.

The invention discloses a method for recycling iron phosphate and graphite from residues obtained after valuable metal is extracted from waste lithium battery black powder. The method comprises the following steps: carrying out alkali solution reaction on ferrophosphorus residues obtained after lithium is extracted from lithium iron phosphate black powder, so that elements such as phosphorus, aluminum and titanium are all dissolved in a liquid phase, and the iron element generates ferric hydroxide which is left in alkali-soluble residues; the alkali-soluble residues are soaked in an ammonia complexing solution to remove impurities such as copper and nickel, and then are neutralized by an acid solution with relatively low concentration to obtain an iron salt solution and graphite carbon residues; oxidizing roasting, flotation, purification and drying are carried out on graphite carbon residues, negative electrode carbon residues obtained after valuable metal is extracted from waste ternary lithium battery black powder after optional preliminary purification, and graphite carbon residues obtained after lithium and ferrophosphorus are extracted from current lithium iron phosphate black powder, so that graphite can be recycled; and acid is added into the alkali dissolution filtrate to adjust the pH value to 6.0-9.0, and then the temperature is raised to hydrolyze impurity salts such as aluminum, titanium and chromium dissolved out of the phosphate solution to form hydroxides and metatitanic acid precipitates to be removed, so that finally, the quality of the iron phosphate prepared by the method disclosed by the invention is ensured to reach related standards.

A method and system of extracting iron oxide from ore is provided, which may include adding a chelating agent to an iron ore to form an iron ore and chelating agent solution, heating the solution to reflux in water, and filtering the solution to yield an extraction residue and a chelated iron solution. The chelated iron solution may be treated with a potassium hydroxide and water solution to yield iron hydroxide.

The invention discloses a titanium white waste acid treatment process, and relates to the technical field of industrial waste regeneration. The titanium white waste acid is subjected to microfiltration and membrane electrolysis treatment, sulfuric acid is separated and recycled under the control of constant pressure and constant current, and residual liquid is subjected to electrodialysis treatment to oxidize ferrous ions into ferric hydroxide precipitates and calcined into ferric oxide; carrying out reduction leaching on the titanium-containing material, hydrolyzing to generate metatitanic acid, and calcining to obtain titanium dioxide; oxidizing the hydrolysate to precipitate vanadate, and calcining to obtain vanadium pentoxide; adjusting the pH value of the filtrate, selectively adsorbing scandium through a biological adsorption column, precipitating and calcining the eluent to obtain scandium oxide, and regenerating and recycling the adsorbent through acid pickling. According to the process, through multi-stage treatment and biological adsorption, resource recycling of sulfuric acid, iron, titanium, vanadium and scandium components in the waste acid is achieved, the process is clean and efficient, secondary pollution of a traditional process is avoided, and a green low-carbon solution is provided for waste acid treatment in the titanium dioxide industry.

This invention provides a one-dimensional silver nanostructure / metal hydroxide composite material, its preparation method, and its application. The preparation method includes: adding a one-dimensional silver nanostructure, a metal salt, and an additive to a solvent and stirring to disperse them evenly; adding an acidic or alkaline reagent under stirring conditions to adjust the pH of the solution, causing the metal ions in the solution to convert into metal hydroxide precipitates, obtaining a one-dimensional silver nanostructure-metal hydroxide suspension; then performing solid-liquid separation, washing and drying the obtained solid product to obtain a one-dimensional silver nanostructure / metal hydroxide composite powder; wherein the metal hydroxide is aluminum hydroxide, zinc hydroxide, magnesium hydroxide, iron hydroxide, manganese hydroxide, copper hydroxide, nickel hydroxide, or cobalt hydroxide, and the one-dimensional silver nanostructure is silver nanowire or silver nanoribbon. The resulting composite material uses metal hydroxide as a carrier and separator, inhibiting the drying and agglomeration of silver nanowires from the source, exhibiting high conductivity and good redispersibility, thus improving conductivity.

The invention discloses a treatment method of ferric hydroxide-based iron-manganese slag. The treatment method comprises the following steps: roasting the iron-manganese slag in a reducing atmosphere; carrying out wet magnetic separation on the roasted slag in a magnetic field to obtain iron powder and non-magnetic slag; carrying out oxidation impurity removal on the non-magnetic slag; carrying out manganese leaching on the non-magnetic slag subjected to oxidation impurity removal to obtain manganese carbonate and waste liquid; and recycling the waste liquid. According to the scheme provided by the invention, the iron-manganese slag is subjected to roasting, magnetic separation, oxidation impurity removal, manganese leaching, waste liquid recycling and the like, so that all-component high-value utilization of the iron-manganese slag is realized.

The invention belongs to the technical field of waste resource utilization, and provides a separation method for valuable metals in an acid leaching solution. After the pH value of the acid leaching solution is adjusted to be alkaline, the obtained alkaline solution is mixed with gas containing carbon dioxide in a spraying or aeration mode for reaction. According to the method, magnesium ions and aluminum ions in the acid leaching solution are converted into basic carbonate and calcium ions are converted into carbonate by utilizing carbon dioxide and liquid caustic soda; compared with hydroxide, basic carbonate and carbonate cannot adsorb lithium ions and rare earth ions in an acid leaching solution, ferric hydroxide formed by a small amount of iron ions has limited adsorption on the lithium ions, and efficient separation and recovery of the lithium ions can be achieved. Furthermore, the carbon dioxide-containing gas is carbon dioxide-containing tail gas, and the separation method can utilize the carbon dioxide gas in the tail gas, so that the carbon emission is reduced.

The invention discloses a method and system for synchronously removing nitrate nitrogen in wastewater and hydrogen sulfide in biogas based on iron circulation, and belongs to the technical field of industrial sewage treatment and biogas purification. According to the invention, iron ions are used as a medium to construct a closed cycle, and biogas and wastewater are synchronously purified; the method comprises the following steps: oxidizing hydrogen sulfide in biogas by using a ferric sulfate solution to generate ferrous sulfide, elemental sulfur and sulfuric acid; then sulfuric acid is separated from a mixture of ferrous sulfide and elemental sulfur through solid-liquid separation, then the ferrous sulfide and the elemental sulfur are subjected to autotrophic denitrification with nitrate in the wastewater under the action of thiobacillus denitrificans, and ferric hydroxide, nitrogen and sulfate are generated; and then the ferric hydroxide reacts with the separated sulfuric acid to regenerate a ferric sulfate solution which is reused in the desulfurization step. In the whole process, cyclic utilization of iron ions is achieved, hydrogen sulfide and nitrate nitrogen are synchronously converted into harmless nitrogen, elemental sulfur and sulfate, and the purposes of treating waste with waste and recycling resources are achieved.