21 results about "Oxalate precipitation" patented technology

The application provides a high-value recycling method of rare earth oxalate precipitation wastewater, and the method comprises the following steps: (1) under the condition of field strengthening, mixing the rare earth oxalate precipitation wastewater and an alkaline calcium salt, and obtaining a calcium oxalate precipitation and a calcium salt solution after neutralization reaction; (2) under the condition of field strengthening, mixing the rare earth chloride and the calcium oxalate precipitation, and obtaining a rare earth oxalate precipitation and a calcium chloride solution after displacement reaction; (3) mixing the rare earth sulfate, the calcium salt solution and the calcium chloride solution, and obtaining a calcium sulfate precipitation and a rare earth chloride solution after precipitation reaction. The method provided by the application not only realizes harmless treatment of the rare earth oxalate precipitation wastewater, but also realizes high-value recycling of the oxalic acid resources in the wastewater, and high-value building material calcium sulfate is prepared, waste is turned into treasure, cost is reduced and benefit is increased, and no salt-containing wastewater is discharged, so that the method is a new green and low-cost rare earth oxalate precipitation wastewater resource recycling technology, and promotes green and sustainable development of the rare earth industry.

The invention provides a method for recovering scandium from scandium-containing lithium slag and a pretreatment method of the scandium-containing lithium slag. The method for recovering scandium from the scandium-containing lithium slag comprises the following steps: mixing the scandium-containing lithium slag with concentrated sulfuric acid, and heating and roasting to obtain a roasted product; the roasted product is subjected to water leaching, and scandium-containing leaching liquid and leaching residues are obtained; the scandium-containing leachate is extracted, and a scandium-containing organic phase and raffinate are obtained; washing the scandium-containing organic phase to obtain a purified scandium-containing organic phase and a washing solution; carrying out reverse extraction on the purified scandium-containing organic phase, and filtering to obtain a reverse extract; the reverse extract is subjected to acid dissolution, and a scandium-containing acid solution is obtained; adding oxalic acid into the scandium-containing acid solution for precipitation, filtering to obtain scandium oxalate precipitation, and roasting to obtain scandium oxide.

The application provides a method for treating and recycling iron-containing waste sulfuric acid in titanium dioxide production, which is based on screening of a strain capable of treating iron-containing waste water in a low pH environment, and establishes a method for treating iron-containing waste sulfuric acid, which can effectively realize resource recycling. The waste water treatment bacteria used are Bacillus QD-QJ-062 strain, and the preservation number is CGMCC No.33725. The QD-QJ-062 strain of Bacillus screened by the application can effectively treat the iron-containing waste water in a low pH environment, promote the generation of ferrous oxalate precipitation, and generate ferrous oxalate by-products. The generated ferrous oxalate can be converted into ferrous sulfate by sulfuric acid, and oxalic acid can be recycled, thereby reducing the operation cost. The sulfuric acid solution after iron removal can be neutralized by limestone to generate high-purity gypsum, thereby realizing resource recycling and treatment.

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

The invention discloses a method for treating a waste lithium battery by using an ultrasonic-enhanced deep eutectic solvent. The method comprises the following steps: pretreating the waste lithium battery to obtain positive electrode material powder; mixing the hydrogen bond donor and the hydrogen bond acceptor to form a deep eutectic solvent; adding the positive electrode material powder into a deep eutectic solvent, and performing leaching reaction under the action of an ultrasonic external field to obtain filtrate and filter residues; adding a precipitator into the filtrate, and reacting under the ultrasonic-assisted action to obtain lithium carbonate, carbonate or oxalate precipitate and post-precipitation liquid; treating the precipitated liquid to obtain a purified deep eutectic solvent for recycling; and washing and drying the lithium carbonate, carbonate or oxalate precipitate to obtain a nickel-cobalt-manganese precursor and battery-grade lithium carbonate. According to the method, the mass transfer problem caused by high viscosity of the deep eutectic solvent is solved by means of the cavitation effect and the micro-jet effect through the ultrasonic external field strengthening technology, the high leaching rate of key metal is achieved, meanwhile, the reaction time is shortened, and the process economy and industrial feasibility are improved.

The invention provides a lithium battery positive electrode material and a regeneration method thereof, and belongs to the technical field of waste battery recycling. The method comprises the following steps: preparing a deep eutectic solvent formed by oxalic acid dihydrate and betaine hydrochloride and / or choline chloride; the method comprises the following steps: pretreating waste NCM positive electrode materials in different proportions, mixing the pretreated waste NCM positive electrode materials with a solvent to form a selective leaching system, and performing coordination precipitation reaction to realize high-selectivity leaching of lithium and oxalate precipitation of transition metal; and mixing and calcining the obtained precipitate and a lithium source, and directly regenerating to obtain the positive electrode material with a specific stoichiometric ratio. The method can efficiently treat the mixed waste materials in a short time, and is simple in technological process, high in metal recovery rate and environmentally friendly.

This application relates to the field of battery cathode materials, and in particular to a high-tap-density lithium-rich manganese-based cathode material and its preparation method. In this application, phosphate and oxalate are used as precipitants, and a certain amount of polymer resin is added. The polymer resin participates in the oxalate precipitation process, followed by sintering. Simultaneously, high-speed stirring and ultrasonic treatment are used to obtain a relatively dense particle system, which also improves the temperature tolerance of the processing. This method enables the achievement of high tap density and good electrical performance even with certain temperature fluctuations.

The application belongs to the technical field of scandium separation and purification, and particularly relates to a method for separating and purifying scandium from crude nickel-cobalt hydroxide, which comprises the following steps: using 0.1-0.5 mol / L dilute sulfuric acid to leach the crude nickel-cobalt hydroxide, and filtering to obtain a scandium-containing leaching solution, wherein the ratio of the dilute sulfuric acid to the crude nickel-cobalt hydroxide is (3-5) mL:1 g, and the molar ratio of sulfuric acid to scandium is (3-5):1; using an extractant comprising Cyanex572 and Aliquat336 to treat the scandium-containing leaching solution to obtain a scandium-containing organic phase; using an oxalic acid solution to back-extract the scandium-containing organic phase to obtain scandium oxalate precipitation; and calcining the scandium oxalate precipitation to obtain scandium oxide. The technical scheme adopts a selective leaching process to realize efficient separation of scandium from main metals nickel and cobalt at the front end, has low reagent consumption, a short process, and great cost advantages; a new type of synergistic extraction technology is adopted, which has super-high selectivity and extraction capacity for scandium, the prepared scandium oxide has a purity of greater than or equal to 96%, and the scandium recovery rate is greater than or equal to 89%.

The invention provides a method for treating and recycling iron-containing waste sulfuric acid in titanium dioxide production, which is a method for treating iron-containing waste sulfuric acid on the basis of screening strains for treating iron-containing waste water in a low-pH environment, and can effectively realize resource recycling. The used wastewater treatment bacterium is a bacillus QD-QJ-062 strain, and the preservation number of the bacillus QD-QJ-062 strain is CGMCC (China General Microbiological Culture Collection Center) No. 33725. The screened bacillus QD-QJ-062 strain can be used for effectively treating iron-containing wastewater in a low-pH environment, the generation of ferrous oxalate precipitate is promoted, and a ferrous oxalate byproduct is generated. The generated ferrous oxalate can be converted into ferrous sulfate through sulfuric acid, oxalic acid is recycled, the operation cost is reduced, the sulfuric acid solution subjected to iron removal can be neutralized through limestone, high-purity gypsum is generated, and resource recycling treatment is achieved.

The invention discloses a method for re-synthesizing a ternary lithium battery positive electrode material from a decommissioned ternary battery, which comprises the following steps: (1) discharging, roasting, disassembling and grinding the decommissioned ternary battery to obtain the required positive electrode material; (2) mixing the positive electrode material with ammonium bisulfate, grinding, calcining at high temperature, leaching with pure water to obtain a material, and heating the material in a water bath; (3) carrying out suction filtration on the material heated in the water bath to obtain a stock solution, adding an oxalic acid solution into the stock solution, mixing and stirring, adding ammonia water, regulating the pH value, preserving heat, standing, and carrying out suction filtration on the solution to obtain an oxalate precipitate; and (4) drying the oxalate precipitate, performing high-temperature calcination to obtain a (Ni0. 5Co0. 2Mn0. 3) 3O4 precursor, and adding lithium carbonate into the obtained precursor to supplement lithium to obtain the ternary lithium battery positive electrode material. According to the preparation method of the positive electrode material, metal elements can be uniformly mixed on the atomic level, and the ternary positive electrode material with excellent performance is synthesized.

This invention discloses a solid waste-based highly active carbon material and its preparation method. It uses industrial waste distiller's grains and spent lithium-ion battery cathode materials as raw materials. The distiller's grains are crushed into particles, while the cathode materials are separated by acid dissolution and oxalate precipitation to obtain a lithium-ion solution and a transition metal oxalate precipitate. Cerium metal salt is added to the precipitate to obtain a non-lithium multi-metal precursor. The resulting distiller's grain particles and multi-metal precursor are then mixed and activated to modify the carbon material with transition metals. Finally, the carbon material is impregnated in the obtained lithium-ion solution and calcined at high temperature to obtain the final solid waste-based highly active carbon material. This invention uses solid waste as raw material and can fully utilize the various active metal components in spent lithium-ion batteries. The resulting solid waste-based highly active carbon material has good capture efficiency for organic molecules in high-temperature exhaust gases, thus possessing promising prospects for large-scale industrial preparation and application.

The invention relates to a device and method for promoting continuous operation of oxalate precipitation through ultrasonic assistance, the device comprises a reactor and a mixer, a stock solution pump and a precipitant pump are respectively connected with the top and the left end of the mixer through pipelines, the mixer is connected with an inlet of the reactor, an outlet of the reactor is connected with an alternate filter, and the alternate filter is connected with a mother liquor storage tank; a nitrate solution and an oxalic acid solution are respectively sent into a mixer for mixing through a stock solution pump and a precipitant pump, and then sent into a reactor for precipitation reaction, slurry is transferred into a filter, and solid-liquid separation is realized through vacuum filtration. The ultrasonic technology is applied to the continuous flow tubular reaction device, formation of oxalate is promoted through the ultrasonic enhancement technology, the reaction liquid mixing effect is further improved, the reaction time is shortened, slurry obtained after reaction is directly filtered, aging time is not needed, and continuous operation of the device is achieved. Meanwhile, the ultrasonic enhancement technology can effectively prevent the pipeline from being blocked, long-term stable operation of the device is achieved, and automatic operation is completed.

The application provides a high-efficiency green high-purity hafnium oxide preparation method, which comprises the following steps: melting hafnium oxide raw materials, solid alkali and fluxing agent to obtain alkali melting clinker; adding the alkali melting clinker into deionized water to perform leaching and filtration to obtain hafnium hydroxide precipitation; adding the hafnium hydroxide precipitation into concentrated sulfuric acid to obtain hafnium sulfate solution; adding a composite chelating agent into the hafnium sulfate solution to remove the precipitation to obtain low-zirconium hafnium sulfate solution; adding activated carbon into the low-zirconium hafnium sulfate solution to filter to obtain hafnium sulfate solution; evaporating and concentrating the hafnium sulfate solution and crystallizing to obtain hafnium sulfate crystal; adding the hafnium sulfate crystal into concentrated hydrochloric acid and refluxing, evaporating and cooling and crystallizing to obtain hafnium oxychloride crystal; dissolving the hafnium oxychloride crystal in water and adding oxalic acid to generate hafnium oxalate precipitation; and calcining the hafnium oxalate precipitation. The hafnium oxide obtained by the method has a purity of 99.995% or more and the zirconium impurity is reduced to 5 ppm or less.

The invention belongs to the technical field of metal material preparation, and particularly relates to a method for recycling and preparing a high-purity aluminum additive from aluminum oxide red mud. Comprising the following steps: leaching a high-purity Al element in the red mud; the preparation of the composite optical dispersion liquid comprises the following steps: preparing carbon-coated aluminum hydroxide micro powder by a hydrothermal carbonization method; and performing multi-stage pyrolysis and calcination on the carbon-coated aluminum hydroxide micro powder. According to the method, Fe in the red mud powder is leached through oxalic acid to obtain Fe-Al leaching liquid, then nanometer materials are added for light treatment with different intensities, oxalic acid in the leaching liquid is decomposed, meanwhile, generated electrons are fully reduced and stably combined to generate ferrous oxalate precipitates, Fe is removed from the leaching liquid, and the high-purity Al leaching liquid is obtained; the whole flow process is simple, the Al element in the red mud can be well recycled, the purity of Al in the leachate is high, and a foundation can be provided for subsequent preparation of high-purity aluminum.

The utility model provides a device for removing sodium oxalate in a Bayer process aluminum oxide production process, and relates to the technical field of aluminum oxide production. The device comprises a reaction system, a seed crystal preparation system and a filtering system which are respectively connected with the reaction system, and an aluminum oxide stock solution system and an ingredient sintering system which are respectively connected with the filtering system, and the seed crystal preparation system comprises a vertical filter press. The method can realize the removal of sodium oxalate in the Bayer process alumina production process, thereby improving the influence of oxalate precipitation in the Bayer process alumina system decomposition process, and enhancing the product quality and production efficiency of Bayer process alumina production.

The invention discloses a method for recycling rare earth oxalic acid precipitation mother liquor. Belongs to the technical field of rare earth processing. The method is technically characterized by comprising the following steps: (1) adding an oxalic acid precipitant, namely adding the oxalic acid precipitant into rare earth oxalic acid precipitation mother liquor for dissolution and precipitation reaction to obtain pretreated oxalic acid precipitation mother liquor; (2) primary pH adjustment: adjusting the pH value of the pretreated grass precipitation mother liquor obtained in the step (1) to 2-5 to obtain the grass precipitation mother liquor after pH adjustment; (3) primary filter pressing; (4) secondary pH adjustment: adjusting the pH value of the filter-press wastewater obtained in the step (3) to 3-8 to obtain the pH-adjusted filter-press wastewater; (5) secondary filter pressing; (6) evaporative crystallization: carrying out evaporative crystallization on the ammonium chloride solution obtained in the step (5), separating ammonium chloride crystals in a centrifugal machine, and recovering condensed water; the invention aims to provide the method for recycling the rare earth oxalic acid precipitation mother liquor, which is novel in process, relatively low in treatment cost and good in effect. The method is used for treating rare earth oxalic acid precipitation mother liquor.

The present application relates to a kind of device and method for regulating metal oxalate precipitation morphology, the device includes first-stage micro-mixer and second-stage micro-mixer in series with the first-stage micro-mixer, the outlet end of the first-stage micro-mixer is connected with the inlet end of the second-stage micro-mixer by pipeline, and the outlet end of the second-stage micro-mixer is also connected with collector by pipeline.The method is: the nitric acid solution in the first syringe, the europium nitrate solution in the second syringe and the oxalic acid solution in the third syringe are mixed to obtain precipitate and mother liquor, and the precipitate is dried after washing to obtain metal oxalate precipitate with different morphology, wherein the nitric acid solution and / or oxalic acid solution is added to the mixture at different flow rates.Compared with prior art, the present application can effectively regulate the morphology of metal oxalate precipitate in real time by changing the flow rate of raw materials, and the flow rate parameters of raw materials are easy to adjust, so that continuous batch operation can be realized.

The invention relates to the technical field of rare earth oxalate recovery, and discloses a rare earth oxalate precipitation device, which is used for mixing oxalic acid and rare earth ions and then collecting, and comprises a precipitation box, and a rotating assembly used for stirring the mixture and scraping precipitates attached to the surface of the inner cavity of the precipitation box is arranged in the middle of the inner cavity of the precipitation box. A discharging assembly used for discharging waste water is arranged at the bottom of an inner cavity of the settling tank and comprises a fixing block, the fixing block is fixedly connected to the bottom of the inner cavity of the settling tank, and a feeding assembly used for automatically putting oxalic acid and rare earth ions into the settling tank is arranged at the top of the inner cavity of the settling tank. The connecting rod rotates to drive the rotating shell to rotate and slide up and down at the same time, so that the stirring rod slides up and down while revolving with the connecting rod as the circle center, it is ensured that rare earth oxalate in the settling tank is uniformly stirred, and the multi-dimensional stirring mode is beneficial to breaking of the agglomeration and layering phenomena between materials; and the stirring uniformity and efficiency are improved.

The invention discloses a recovery method of waste lithium battery pickle liquor, and relates to the technical field of battery recovery. The copper in the battery powder pickle liquor is removed by a two-stage method, and the purpose of deep copper removal is achieved through a nickel-iron alloy replacement reaction and an oxalic acid precipitation reaction in sequence; fe < 3 + > and oxalate are complexed into a stable complex ion [Fe (C2O4) 3] < 3-> under a specific pH condition (2.0-2.5), so that the loss of an iron element in an aluminum precipitation process can be prevented, new impurities are not introduced, and segmented impurity removal of iron and aluminum is realized; and adjusting the pH value to 4.5-4.8, reacting to precipitate aluminum in the form of sodium aluminum oxalate crystals, and synthesizing iron phosphate by using the liquid after aluminum precipitation. According to the method provided by the invention, impurities such as copper, iron and aluminum can be removed and recovered stage by stage, so that purification and impurity removal of the leachate are realized, resource recovery of copper, iron and aluminum is also realized, and meanwhile, generation of hazardous wastes is reduced.

The present application relates to a kind of based on organic sulfonic acid scandium double salt precipitation scandium recovery method, comprising: using sulfuric acid to the scandium concentrate is treated by acid immersion to obtain the scandium-containing leaching solution;Scandium-containing leaching solution is adjusted to alkaline pH, and precipitate to obtain coarse scandium hydroxide;Coarse scandium hydroxide is reacted with organic sulfonic acid to obtain organic sulfonic acid scandium salt;Organic sulfonic acid scandium salt is mixed with saturated sulfate solution and carries out double salt precipitation, and separation is obtained containing scandium double salt;Scandium double salt is washed, precipitated by ammonia, acid dissolution, oxalate precipitation and high temperature calcination, and high-purity scandium oxide is obtained.The present application combines organic sulfonic acid scandium salt and sulfate for the first time to construct a new double salt precipitation system, which can realize efficient and high-selectivity separation of scandium, various rare earth elements and conventional metal impurities in a single precipitation, and obtain scandium oxide with purity higher than 99.9%.The total recovery rate of scandium is more than 85%.The process is simple, without complex saponification process, reducing the generation of salt-containing and ammonia-containing wastewater, and reducing equipment investment and operating cost.

The invention belongs to the technical field of radiation environment monitoring, and particularly relates to an automatic sample preparation system of an environment sample strontium-90 nuclide sample source. Comprising a unit for generating yttrium oxalate precipitates in the desorption liquid and a suction filtration sample preparation unit of the precipitates, the unit for generating the yttrium oxalate precipitates in the desorption liquid comprises a plurality of reagent liquid storage bottles, a first switching valve, a first beaker and an automatic PH adjusting unit, the first switching valve is connected with the first beaker through a pipeline, the first beaker is installed on a magneton stirrer, and the magneton stirrer is connected with the first beaker through a pipeline. An automatic PH adjusting unit is inserted into the top of the first beaker; the precipitation suction filtration sample preparation unit comprises a funnel, quantitative filter paper is mounted in the funnel, the top of the funnel is connected with the top of a first beaker, the lower part of the funnel is arranged in a suction filtration bottle, a second beaker is further arranged in the suction filtration bottle, and the top of the funnel is connected with a second switching valve through a pipeline. The automatic preparation device has the beneficial effects that full-automatic preparation of the strontium-90 sample source is realized through automatic control, manual operation is replaced, and the preparation time of the sample source is remarkably shortened.