36 results about "Sodium Vanadate" patented technology

The present application relates to a kind of rack steel layered casting composite flux and its preparation, method for using, the component and content of composite flux are as follows: high-purity iron powder: 40%~50%, high-purity rare earth powder: 20%~30%, analytical pure sodium pyrovanadate: 20%~40%.Using layered casting process of composite flux with rack steel, the macrosegregation and shrinkage cavity defects of large rack steel ingot can be significantly improved, which provides a simple, feasible and effective way to improve the composition homogenization degree of ingot, helps to improve the overall quality of rack steel ingot, also shortens the production cycle and improves the production efficiency, thereby improves the production capacity of large rack steel ingot, reduces the production energy consumption and production cost;The present application has important significance for breaking through the bottleneck of high homogenization large rack steel ingot manufacturing, laying the new technical theoretical foundation and industrialization application of large rack steel ingot casting, and improving the manufacturing technology level of key components of large equipment in China.

The invention belongs to the technical field of energy storage batteries, and particularly relates to a method for preparing a vanadium oxide electrolyte based on a sodium vanadium oxide solution and a vanadium redox flow battery. The method comprises the following steps: S1, sodium treatment leaching: treating a vanadium-containing raw material by adopting a sodium-containing compound to generate a sodium vanadium solution; s2, valence state regulation and control: dividing the sodium vanadium solution into two parts, adjusting the pH value of the first part to be acidic, and then adding a reducing agent to carry out a reduction reaction to obtain a negative electrode electrolyte containing V < 3 + > / V < 4 + >; and adding an oxidizing agent into the second part for oxidation reaction to obtain the positive electrode electrolyte containing V < 4 + > / V < 5 + >. According to the method, the vanadium slag is used for replacing high-purity V2O5 to prepare the electrolyte, so that the cost of raw materials is reduced; according to the electrolyte prepared by the invention, the energy efficiency of the battery is high; meanwhile, the preparation method disclosed by the invention adopts an integrated process, and an intermediate product treatment link is omitted, so that the preparation steps are simpler, and the production efficiency is remarkably improved.

The application discloses a kind of high-efficiency heterogeneous catalyst for CO2 ring addition preparation cyclic carbonate and its preparation method and application, belong to catalyst technical field.The high-efficiency heterogeneous catalyst is transition metal doped polyoxometalate coordination polymer, chemical general formula is C 16 H 58 M2N2Na2O 48 V 10 Wherein, M is selected from Co 2+ , Ni 2+ , Cu 2+ Or Zn 2+ Its preparation method is: sodium vanadate, transition metal acetate and bis (2-hydroxyethyl) amino (trihydroxymethyl) methane ligand are dissolved in water with pH being 1~3, stirring reaction, after filtration, crystallization is stationary, and is obtained.In the ring addition reaction of CO2 and epoxide, the catalyst and cocatalyst tetrabutylammonium bromide synergistic effect, catalytic yield can be up to 98.2%, selectivity is more than 99%, and catalytic activity still remains at 88% after recycling five times.

The invention discloses a catalyst for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through continuous catalytic hydrogenation and a preparation method and application thereof, the catalyst comprises a carrier, and an active component platinum and an auxiliary component which are loaded on the carrier, the auxiliary component is at least one of sodium citrate, disodium ethylene diamine tetraacetate, sodium metavanadate, oxalic acid, zirconium oxychloride, yttrium nitrate or sodium carbonate; and the active component and the auxiliary component both account for 0.1-10% of the mass of the catalyst. The catalyst is used for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through hydrogenation, the reaction can be continuous, the safety performance is better, and the catalyst has high catalytic activity and stability.

The invention relates to a method for green vanadium precipitation and sodium-ammonium circulation of a sodium modified vanadium solution, and belongs to the technical field of hydrometallurgy. The method comprises the following steps: adding hydrochloric acid and ammonium chloride into the sodium vanadium solution, adjusting the pH value, carrying out heating reaction, and carrying out solid-liquid separation to obtain ammonium polyvanadate and vanadium precipitation wastewater; adding a reducing agent into the vanadium precipitation wastewater for reduction reaction; adding a polycarboxylic acid water reducer, adjusting the pH value with ammonia water, and carrying out solid-liquid separation to obtain purified wastewater and vanadium-chromium filter residues; introducing carbon dioxide gas into the purified wastewater until the purified wastewater is saturated, cooling, crystallizing, and carrying out solid-liquid separation to obtain sodium bicarbonate solid and crystallization mother liquor; and evaporating and concentrating the crystallization mother liquor until the concentration of ammonium chloride is 65-75g / L, then cooling and crystallizing at the temperature of-10-20 DEG C, and carrying out solid-liquid separation to obtain ammonium chloride solid and residual wastewater. According to the invention, high-efficiency and high-purity recovery of sodium and ammonium ions and closed circulation of the system are realized, and the problems of sodium and ammonium circulation and impurity accumulation in the traditional process are solved.

According to the method for preparing the vanadium electrolyte through targeted impurity removal and one-step vanadium precipitation of the sodium-modified vanadium solution, high-purity ammonium metavanadate is prepared through targeted impurity removal of the sodium-modified vanadium solution, and calcination is conducted under the protection of inert gas of ammonium metavanadate, so that the consumption of auxiliary materials and the generation amount of waste water are greatly reduced; the manufacturing process cost of the vanadium electrolyte is effectively reduced; by adopting a two-time silicon removal mode, the use amount of a silicon removal agent is reduced while high-efficiency removal of chromium is realized, and the generation amount of silicon removal slag and the vanadium loss in the silicon removal process are reduced. In addition, the pH value of the liquid subjected to deep silicon removal is lower than that of the liquid subjected to chromium removal, so that the aluminum concentration of the liquid subjected to deep silicon removal can be effectively reduced, and conditions are created for improving the subsequent hydrolysis aluminum removal effect; the crude ammonium metavanadate is pulped and washed by adding a complexing agent, the content of cations such as potassium, sodium and calcium is reduced, the ammonium metavanadate is calcined under the protection of inert gas to obtain low-valence vanadium oxide, the acid solubility of the vanadium oxide is improved, and the consumption of a reducing agent in the preparation process of the vanadium electrolyte is reduced.

This invention belongs to the field of battery electrode material technology, and discloses a calcium-doped sodium vanadate electrode material, its preparation method, and its application in aqueous ammonium-ion batteries. The preparation method includes the following steps: vanadium pentoxide is dispersed in water, hydrogen peroxide is added and stirred, and calcium nitrate and sodium hydroxide are added. The resulting mixed solution is transferred to a reaction vessel for hydrothermal reaction. After cooling to room temperature, the sample is washed, freeze-dried, and collected. When the calcium-doped sodium vanadate cathode material is applied to an aqueous ammonium-ion battery, electrochemical test results show that when paired with a 3,4,9,10-perylenetetracarboxylate diimide anode, it exhibits high reversible specific capacity and excellent rate performance, demonstrating its outstanding comprehensive electrochemical performance and great potential in practical energy storage applications. This invention features a simple synthesis route, is environmentally friendly, has low raw material costs, and the overall process has industrial application potential, making it suitable for promotion and application as a novel energy storage device.

The utility model discloses a device for preparing ammonium polyvanadate by continuously crystallizing a sodium vanadate solution. The device comprises a premixing tank, a liquid storage tank, a reaction kettle and a filter press, the premixing tank is provided with a sodium vanadate solution inlet, an ammonium sulfate inlet and a sulfuric acid inlet, an outlet of the premixing tank is communicated with an inlet of the liquid storage tank, an outlet of the liquid storage tank is communicated with an inlet of the reaction kettle, and an outlet of the reaction kettle is communicated with an inlet of the filter press; the reaction kettle is provided with a heating structure and a sulfuric acid inlet. According to the device, the pre-mixing tank is independently arranged, the process in the pre-mixing tank is controlled in the use process, so that no crystal precipitate is generated in the pre-mixed vanadium liquid, and the crystallization process is performed in the reaction kettle through the transition of the liquid storage tank, so that the stability of the ammonium polyvanadate crystallization process can be improved, and the particle size of the ammonium polyvanadate can be increased to reduce the cleaning difficulty; the stability and purity of the ammonium polyvanadate in the crystallization process are improved, and meanwhile the particle size of the ammonium polyvanadate is increased.

This invention belongs to the field of battery cathode material technology, specifically relating to an Al 3+ Sodium vanadate-coated nanocomposites, their preparation methods, and applications. The Al... 3+ Sodium vanadate-coated nanocomposite material, made of Al 3+ The sodium vanadate is coated to obtain the product. The vanadium in the sodium vanadate is pentavalent. Under bridging and coordination, the pentavalent vanadium self-assembles to form a polynuclear vanadium-oxygen cluster anion [V6O]. 16 ] 2‑ Al 3+ [V6O] on the surface of sodium vanadate 16 ] 2‑ The formation of surface complexes of the type =Al-O-V≡ coats sodium vanadate, forming Al 3+ Vanadic acid-coated nanocomposite materials. The Al of this invention... 3+ @NVO has a stable structure, and the batteries made from it have high discharge capacity and high rate performance.

The application discloses a method for preparing vanadium oxide from high-concentration vanadium sodium solution, which comprises the following steps: S1, directly hydrolyzing and precipitating vanadium from high-concentration vanadium solution with a vanadium concentration of 40-140 g / L to obtain filter cake after filtration; S2, beating the filter cake with low-sodium ammonium-containing solution with a sodium concentration of less than or equal to 25 g / L, and then performing crystallization by adding acid to the obtained slurry to adjust the pH to 2.0-2.5 and by heating to 80-90 DEG C, and then obtaining ammonium polyvanadate after filtration; and S3, calcining or reducing the ammonium polyvanadate to obtain vanadium oxide. The application can reduce vanadium precipitation wastewater, improve the quality of ammonium polyvanadate, and also can reduce the use amount of ammonium salt.

The scheme provides a cleavage method of low molecular weight aldehyde carboxyl rubber, which comprises the following steps: dissolving rubber in an organic solvent to obtain a rubber solution; heating the rubber solution, adding sodium metavanadate solution and mixing uniformly to obtain a mixed solution; adding hydrogen peroxide drop by drop into the mixed solution until the cleavage reaction is completed to obtain a reaction solution, wherein the molar ratio of the total amount of hydrogen peroxide to the carbon-carbon double bond in the rubber is (1.2-2.5):1; and treating the reaction solution to obtain low molecular weight aldehyde carboxyl rubber. The method can reduce the cost, improve the environmental protection, significantly improve the functional group content and reaction efficiency of the product, and provide a better choice for the large-scale production and application of low molecular weight aldehyde carboxyl rubber.

The invention belongs to the field of metallurgy, and discloses a clean vanadium extraction method for sodium salt roasting of vanadium slag. The method comprises the following steps: crushing and screening the vanadium slag to obtain fine powder vanadium slag; sodium salt is added into the fine powder vanadium slag for mixing, then oxidizing roasting is conducted, and roasted clinker is obtained; the roasted clinker is leached to extract vanadium, and vanadium-containing leachate and leached tailings are obtained; sodium metaaluminate is used for desiliconizing the vanadium-containing leaching solution, a sulfur-free chromium removal agent is added for chromium removal, and an impurity removal solution is obtained; concentrating the impurity-removed solution to obtain a concentrated solution and condensed water; after oxidizing the concentrated solution, cooling and crystallizing to obtain hydrated sodium vanadate and crystallized supernatant; after the hydrated sodium vanadate is heated and redissolved, ammonium salt is added for vanadium precipitation, and ammonium metavanadate and redissolved vanadium precipitation supernatant are obtained; performing deamination and oxidation calcination on ammonium metavanadate to obtain vanadium pentoxide, and performing sodium precipitation on the re-dissolving vanadium precipitation supernatant to obtain sodium bicarbonate and a sodium precipitation supernatant. The method provided by the invention realizes clean and efficient vanadium extraction by sodium salt roasting of the vanadium slag.

The invention relates to the technical field of blood miRNA preservation, and particularly discloses a disposable blood miRNA preservation tube and a preservation solution thereof, the preservation solution is composed of the following components: 30 mg / ml of glycine, 3 mg / ml of glutamine, 3 mg / ml of glucose, 600 mg / ml of sodium orthovanadate, 3 mg / ml of aluminum fluoride, 25 mg / ml of acetylcysteine, 300 mg / ml of diazoalkyl urea, 2.0 mg / ml of EDTA-2Na, 6 mg / ml of sorbitol, 6 mg / ml of trehalose, and the balance of water. The preservation tube is good in sealing performance and convenient to use, the preservation liquid can effectively slow down rupture of blood cells, DNA in the blood cells is prevented from diluting and polluting target miRNA, nuclease is prevented from degrading the target miRNA, and the preservation period of a blood sample containing target nucleic acid is prolonged.

The invention belongs to the field of vanadium chemical industry, and particularly discloses a method for preparing anhydrous sodium metavanadate by using sodium vanadium solution. The method comprises the following steps: S1, removing silicon, chromium and aluminum from the sodium modified vanadium liquid to obtain an impurity-removed liquid; s2, concentrating the impurity-removed solution to obtain a concentrated solution; s3, putting the concentrated solution into crystallization equipment, and carrying out standing crystallization at the temperature of 10-30 DEG C to obtain anhydrous sodium metavanadate crystals and post-crystallization liquid; and S4, washing and drying the anhydrous sodium metavanadate crystal to obtain the anhydrous sodium metavanadate. According to the method disclosed by the invention, the anhydrous sodium metavanadate is prepared by taking the sodium vanadium solution as a raw material through impurity removal, concentration, crystallization, washing and drying. According to the method, the anhydrous sodium metavanadate can be prepared at low cost, the purity of the prepared anhydrous sodium metavanadate product is high, the technological process is simple, operation is easy, and the requirement for equipment is low.

This invention relates to the field of galvanized steel technology, and proposes a scratch-resistant galvanized steel strip and its preparation method. The scratch-resistant galvanized steel strip comprises, from bottom to top, a steel strip, a hot-dip galvanized layer, and a passivation layer. During the preparation of the passivation layer, each 1L of passivation solution includes the following components: 5-10g sodium molybdate, 1-2g sodium nitrate, 0.1-0.3g sodium metavanadate, 0.5-0.8g titanylfluoride, and 0.2-0.5g bis(1,6-hexanetriamine)pentamethylenephosphonic acid. This technical solution solves the problems of poor scratch resistance and low surface hardness of existing galvanized steel strips.

This application discloses a method for producing acetonitrile by reacting acetate with ammonia, comprising the following steps: in a reactor, acetate, ammonia, and a catalyst are contacted and reacted to obtain acetonitrile; the acetate is selected from at least one of methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and cyclohexyl acetate; the catalyst is composed of a support and vanadate and alkali metal oxide of active components supported on the surface of the support; the vanadate is selected from at least one of bismuth vanadate, silver metavanadate, ammonium metavanadate, lithium vanadate, lithium metavanadate, sodium vanadate, sodium metavanadate, potassium vanadate, and potassium metavanadate; the alkali metal oxide is selected from at least one of lithium oxide, sodium oxide, and potassium oxide; the support is selected from at least one of silicon oxide, alumina, and molecular sieve; the mass content of vanadate is 0.1–10 wt%, and the mass content of alkali metal oxide is 0.01–5 wt%.

A method for forming a coating layer on a substrate includes the steps of: providing a substrate which is made of a magnesium alloy; preparing a permanganate conversion solution that contains a permanganate salt, sodium vanadate, and a buffering agent; impregnating the substrate and an inert conductive material into the permanganate conversion solution, followed by electrically connecting the substrate to a positive electrode of a power supply to serve as an anode, and electrically connecting the inert conductive material to a negative electrode of the power supply to serve as a cathode; applying a voltage ranging from 2 V to 15 V to the substrate in the permanganate conversion solution using the power supply, so as to form a coating layer on the substrate, thereby obtaining a coated substrate; and removing the coated substrate from the permanganate conversion solution. A coating layer formed by the aforesaid method is also provided.

The invention belongs to the technical field of vanadium compounds, and particularly relates to a sodium vanadate single crystal, a sodium vanadate composite metal single crystal, vanadium pentoxide and a preparation method and application of the sodium vanadate single crystal and the sodium vanadate composite metal single crystal. Vanadium in a system is adjusted to exist in a pentavalent form mainly by adjusting the pH value of the vanadium-sodium leaching solution and the pH value of a mixed system of the vanadium-sodium leaching solution and potassium salt, magnesium salt or cobalt salt, and high-purity large-size single crystals are directly obtained from the leaching solution at the specific crystallization temperature. According to the method, high-purity and large-size single crystals are used as raw materials, the high-purity vanadium pentoxide is obtained through calcination after ammonium salt vanadium precipitation, and the requirements of aviation, aerospace and other special industries for high-purity vanadium products can be met. The preparation method provided by the invention has the advantages that the process is simple, the cost is low, and a high-purity vanadium product can be directly extracted from the vanadium leachate. According to the method, the existence form and solubility of vanadium (V) are controlled by adjusting the pH value and temperature of a solution system, so that efficient crystallization and purification of vanadium compounds are realized.

The invention provides an alkaline impurity removal method for a sodium vanadate solution, which comprises the following steps: adding a calcium remover into the sodium vanadate solution to obtain sodium vanadate mixed slurry after calcium precipitation; adjusting the alkalinity of the sodium vanadate mixed slurry after calcium precipitation to obtain the sodium vanadate mixed slurry after alkalinity adjustment; adding a reducing agent into the alkalinity-adjusted sodium vanadate mixed slurry to reduce high-valence chromium so as to obtain reduction reaction slurry containing chromium precipitates; adding a filter aid into the reduction reaction slurry, stirring, filtering and separating to obtain a mixed chromium-calcium slag filter cake and a chromium-calcium-removed sodium vanadate solution; and adjusting the pH value of the sodium vanadate solution after chromium and calcium removal, stirring, filtering and separating to obtain a mixed silicon slag filter cake and a sodium vanadate purified solution. According to the method, impurities such as chromium, silicon and calcium are removed before vanadium precipitation of the sodium vanadate solution, a foundation is laid for preparation of high-purity vanadium oxide, the treatment difficulty and cost of the acid vanadium precipitation wastewater are reduced, and the purpose of low-cost, rapid and thorough impurity separation is achieved.

The application relates to a preparation method of a novel NiV2S4 and magnesium hydride composite hydrogen storage material and application thereof, the material takes magnesium hydride and NiV2S4 as main components, and belongs to the technical field of magnesium-based hydrogen storage materials. The hydrogen storage material is prepared by mixing magnesium hydride and NiV2S4 through a ball milling process. The preparation method comprises the following steps: firstly, uniformly dispersing nickel chloride hexahydrate, sodium orthovanadate and thiourea into water; then, transferring into a Teflon container and keeping at 150 DEG C-180 DEG C for 12-24 h, washing and drying to obtain NiV2S4. Finally, ball milling the NiV2S4 and magnesium hydride to obtain the magnesium hydride composite hydrogen storage material based on NiV2S4. The composite hydrogen storage material has excellent performance, compared with the ball-milled magnesium hydride, the initial hydrogen release temperature is reduced by 138 DEG C, the hydrogen release amount reaches 6.21 wt% at 350 DEG C in 5 min, the hydrogen absorption amount reaches 4.8 wt% at 150 DEG C in 20 min, and the capacity is greater than 90% after 60 cycles at 300 DEG C.

The application discloses a chemical oxidation treatment solution for aluminum and aluminum alloy and a method thereof, wherein the treatment solution is configured into an aqueous solution according to the following proportions: fluorozirconate, hexafluorozirconic acid, phosphate, rare earth salt, 2-amino benzoic acid, benzotriazole and sodium vanadate, and the pH value of the solution is between 3.5 and 4.3. The chemical oxidation treatment solution has simple components, does not contain elements such as chromium which affect the environment, has low process control requirements, is prepared into a chemical oxidation solution which is used under normal temperature conditions, has a simple process, has high adhesion to an organic paint film, and is suitable for surface treatment of aluminum and aluminum alloy parts in various shapes.

The application provides a vanadium slag cleaning vanadium extraction method and application thereof. The method comprises the following steps: mixing vanadium slag and sodium salt, sintering, adding roasting clinker, water, chromium removal mother liquor and impurity removal slag, leaching to obtain tailings and leaching liquor, removing impurities from the leaching liquor to obtain purified liquor, performing precipitation treatment on the purified liquor to obtain vanadium precipitation mother liquor and calcium vanadate; adding a first reducing agent to the vanadium precipitation mother liquor to obtain chromium hydroxide, calcining to obtain chromium sesquioxide; performing vanadium leaching on the calcium vanadate, carbon dioxide, crystallization mother liquor and calcination tail gas to obtain calcium salt and sodium vanadate solution, evaporating and crystallizing the sodium vanadate solution to obtain sodium metavanadate, performing high-temperature reduction on the sodium metavanadate, an auxiliary agent and a second reducing agent to obtain reduced clinker, and performing sodium removal on the reduced clinker, sodium bicarbonate mother liquor and water to obtain vanadium sesquioxide. The application successfully prepares chromium sesquioxide and vanadium sesquioxide products, and realizes high-value utilization of high-chromium vanadium slag.

The invention belongs to the technical field of organic synthesis, and particularly discloses a composite catalyst and a preparation method and application thereof in synthesis of 4-cyanopyridine, the composite catalyst comprises the following components by weight: 8-10% of an active component, 1-2% of a promoter, 88-90% of a carrier, and 0.5-1% of a performance regulator; the active component is a vanadium source and comprises ammonium metavanadate, vanadium pentoxide and sodium metavanadate; the promoter is a cerium source and comprises cerium nitrate, cerium oxide and cerium oxalate; the carrier is a titanium source and comprises titanium dioxide, tetrabutyl titanate, titanyl sulfate and isopropyl titanate; the performance regulator is graphene quantum dots. According to the composite catalyst and the preparation method thereof, the composite catalyst is applied to the synthesis process of 4-cyanopyridine, a target product can be efficiently prepared in a high-selectivity and low-energy-consumption mode, and then the composite catalyst has the practical value and application potential of industrial continuous production.

The present application relates to a kind of methods for preparing vanadic oxide with high impurity content vanadium-rich solution.The technical scheme is: adding hydrogen peroxide solution to high impurity content vanadium-rich solution, obtaining pretreatment solution;then using precipitant to adjust the pH value of pretreatment solution, carrying out first stirring, solid-liquid separation, obtaining iron-containing precipitate and vanadium-containing solution.Using oxidizing agent to oxidize the potential of vanadium-containing solution to-1100~‑1000mV, obtaining pentavalent vanadium solution, carrying out second stirring to the pentavalent vanadium solution, solid-liquid separation, obtaining sodium polyvanadate and vanadium precipitation mother liquor.Mixing the detergent with sodium polyvanadate, carrying out third stirring, solid-liquid separation, obtaining ammonium polyvanadate and washing waste liquid.Calcining the ammonium polyvanadate at 500~550℃ for 30~60min, obtaining vanadic oxide.The present application has the characteristics of good impurity removal effect, low ammonium consumption and environmental friendliness, and the prepared vanadic oxide has high purity.

The invention discloses a macroporous ZSM-5 molecular sieve loaded heteropolyacid desulfurization catalyst as well as preparation and application thereof, and belongs to the technical field of light fuel oil desulfurization. The method comprises the following steps: adding sodium metavanadate dihydrate, sodium dihydrogen phosphate hydrate and sodium molybdate dihydrate as raw materials into an aqueous solution, adjusting the pH value to about 4, refluxing for 8 hours, cooling, extracting with diethyl ether to obtain vanadium-substituted Dawson type heteropolyacid, and adjusting the material ratio to obtain different amounts of vanadium-substituted heteropolyacid. Then, the supported catalyst POM-CNTs (at) MOF-199-ZSM-5 is prepared through a one-pot method, and the obtained catalyst is applied to oxidative desulfurization of a light fuel simulation system. Oxygen in air is used as an oxidizing agent, and the thiophene removal rate can reach 98.90% after 2.5 h at 70 DEG C.

The invention relates to a method for recovering sodium vanadate from an invalid residual oil hydrogenation catalyst by utilizing ultrasonic microbubble reinforcement. The method comprises the following steps: (1) uniformly mixing the invalid residual oil hydrogenation catalyst and an inorganic salt auxiliary agent, and carrying out grading ball milling; (2) roasting the ball-milled powder under oxygen-enriched gas; (3) oxygen microbubbles are introduced into the roasted mixture, a leaching agent and a leaching auxiliary, ultrasonic action is applied, and a leaching solution is obtained through separation; (4) an impurity removal agent is added into the leachate for separation, and vanadium-containing alkali liquor is obtained; and (5) simultaneously applying ultrasonic waves and oxygen microbubbles to the vanadium-containing alkali liquor to perform enhanced oxidation, and finally performing evaporation concentration, crystallization, separation, washing and drying to obtain sodium vanadate. The method is simple in process, continuous in operation, free of secondary pollution, low in energy consumption and low in agent consumption through whole-process collaborative linkage, and is suitable for industrial large-scale treatment of the invalid residual oil hydrogenation catalyst, so that the dual targets of hazardous waste recycling and environmental governance are achieved.

The application relates to a method for producing high-purity vanadium pentoxide by hydrolysis of vanadium precipitation, which comprises the following steps: adding an ammonium salt into a vanadium-containing solution to obtain an ammonia (ammonium) vanadate solution; preparing a sulfuric acid solution with 1-2 times of the theoretical amount of acid required for converting vanadium in the ammonia (ammonium) vanadate solution into polyvanadic acid; adding the ammonia (ammonium) vanadate solution into the sulfuric acid solution to perform a hydrolysis reaction, controlling the temperature of the hydrolysis reaction system, and making the hydrolysis of vanadium always occur in a boiling acid solution environment to reduce or avoid the precipitation of sodium vanadate; stopping the feeding when the pH of the solution is greater than or equal to 0.5, continuing to stir, and then filtering to obtain red vanadium and a hydrolysis solution; and calcining the red vanadium after acid washing to obtain high-purity vanadium pentoxide products, and returning the acid washing solution to be used as the vanadium hydrolysis solution, so that the H + The ion plays a dual role of sodium washing and vanadium precipitation hydrolysis. The process flow is short, the reagent consumption is small, the product quality is good, the operation is simple, the consumption of the ammonium salt in the vanadium precipitation process and the ammonia nitrogen content in the solution after vanadium precipitation can be remarkably reduced, and the method is suitable for the industrial production and application of vanadium pentoxide.

The application discloses a method for extracting vanadium and removing sodium from sodium vanadium liquid, and belongs to the field of vanadium oxide preparation. The method comprises the following steps: a: adding a vanadium increasing agent into the sodium vanadium liquid to adjust the sodium vanadium ratio, adding acid to adjust the pH value, and then adding ammonia-containing substance to adjust the ammonium vanadium ratio and the pH value, and after precipitation and solid-liquid separation, obtaining sodium ammonium vanadate precipitate and supernatant; b: passing carbon reduction gas into the sodium ammonium vanadate precipitate, and obtaining vanadium trioxide, sodium carbonate and ammonia-containing gas through reduction separation. The method uses sodium vanadium liquid as raw material, adds a vanadium increasing agent into the sodium vanadium liquid to increase the vanadium concentration, adjusts the pH value and adds ammonia-containing substance to realize the simultaneous extraction and removal of vanadium and sodium in the sodium vanadium liquid in the form of sodium ammonium vanadate, passes carbon reduction gas into the sodium ammonium vanadate to realize the effective separation of vanadium and sodium through reduction separation, and prepares high-purity vanadium trioxide product.

The utility model discloses a device for preparing high-purity potassium metavanadate from sodium vanadate in a short process. The device comprises a crystallization reaction kettle, a first filtering device, a digestion reaction kettle and a second filtering device, the crystallization reaction kettle is provided with a sodium vanadate solution inlet, a potassium sulfate inlet, a concentrated sulfuric acid inlet and a heating mechanism; the digestion reaction kettle is provided with a potassium polyvanadate inlet, a potassium hydroxide solution inlet and a heating mechanism; an outlet in the bottom of the crystallization reaction kettle is communicated with an inlet of the first filtering device, a solid material outlet of the first filtering device is connected with a potassium polyvanadate inlet of the digestion reaction kettle, and an outlet in the bottom of the digestion reaction kettle is communicated with an inlet of the second filtering device; a solid material outlet of the No.2 filtering device is connected with a potassium polyvanadate inlet of the digestion reaction kettle. According to the device, spherical potassium metavanadate solid particles with uniform particle size and good fluidity can be prepared, the stability of the potassium metavanadate crystallization process and the vanadium recovery rate are improved, the purity of the obtained potassium metavanadate product is greater than 99.5 wt%, and the vanadium recovery rate is greater than 99%.

The invention discloses molybdenum diselenide coated sodium vanadium phosphate and a preparation method thereof. The preparation method comprises the following steps: uniformly stirring a sodium source, a vanadium source, a phosphorus source, a carbon source and a dispersing agent in pure water, and sanding to obtain slurry; drying the slurry to obtain powder, and sintering the powder to obtain a carbon-coated sodium vanadium phosphate material; crushing the carbon-coated sodium vanadium phosphate material to obtain carbon-coated sodium vanadium phosphate powder; dissolving a molybdenum source in water, adding into the carbon-coated sodium vanadium phosphate powder, stirring, and carrying out vacuum drying to obtain a sodium vanadium phosphate material with the molybdenum source adsorbed on the surface; and vacuumizing the obtained sodium vanadium phosphate material with the molybdenum source adsorbed on the surface and selenium powder to 1-100 Pa, and sintering at 550-650 DEG C to obtain the molybdenum diselenide coated sodium vanadium phosphate positive electrode material. Through molybdenum diselenide coating, the sodium ion conduction capability of the sodium vanadium phosphate material is improved, the rate capability of the material is improved, the material has certain mechanical strength and structural stability, the material stripping phenomenon in the circulation process is reduced, and the electrochemical performance is improved.