22 results about "Oxyvanadium" patented technology

The invention discloses application of bismuth vanadium tetraoxide as a photocatalyst in preparation of allantoin. According to the method, a decahedral single crystal micron material bismuth vanadium tetroxide is used as a photocatalyst, uric acid is used as a substrate, a photocatalytic reaction is performed under the irradiation of visible light, and uric acid is oxidized, hydrolyzed, decarboxylated and converted into allantoin; compared with a traditional chemical synthesis method, the method has the advantages that the bismuth vanadium tetraoxide serves as a photocatalyst, uric acid is converted into allantoin through photocatalytic reaction, selective activation of chemical bonds is achieved through directional regulation and control of photo-induced electron-hole pairs, and the method is mild in reaction condition, low in energy consumption and the like.

The invention discloses a preparation method of ammonium polyvanadate and the ammonium polyvanadate. The method comprises the following steps: carrying out calcium salt roasting and acid leaching on the vanadium slag to obtain a calcified acid leaching vanadium solution; removing lead from the calcified vanadium acid leaching solution to obtain a purified solution; adjusting the pH value of the purified liquid and adding ammonium sulfate; heating, introducing compressed air and ozone, and stirring; and after the compressed air and the ozone are introduced into a preset volume, stopping heating, stirring and standing to obtain ammonium polyvanadate. According to the scheme provided by the invention, ozonation is adopted, so that the vanadium precipitation yield after lead removal can be improved, meanwhile, the subsequent vanadium product quality is not influenced, other impurities are not introduced after oxidation is completed, the vanadium oxide wastewater circulation is not influenced, and the cost of the oxidation process is low.

The invention discloses a method for preparing vanadium metal powder based on a cryolite system, which comprises the following steps: mixing vanadium monoxide (VO) serving as a vanadium source, magnesium metal particles and cryolite in a mass ratio of (10-20): (6-12): (30-60), and roasting and reducing for 2-6 hours at 800-1000 DEG C under the protection of inert gas. After the reaction is completed, leaching a core material in a product by using a 10-15% zirconium chloride and other chloride solution, and drying to obtain metal vanadium powder; and the leached filtrate can be regenerated into cryolite for recycling after being treated. VO is selected as a vanadium source, and consumption of a reducing agent is reduced from the source; the metal magnesium is selected as a reducing agent, the activation energy is reduced by utilizing the higher reaction activity of the magnesium, and the key is that the magnesium and the vanadium are subjected to non-alloying reaction, so that the product purity is fundamentally guaranteed; the cryolite is used for replacing chloride molten salt, so that the obstruction of oxide layer by-products can be effectively broken, the reaction activity can be improved, and the cryolite can be recycled. The method has the advantages of simple process and high product purity, and is especially suitable for the requirements of high-end fields on vanadium materials.

The invention provides an aqueous cadmium ion-vanadium dioxide battery as well as a preparation method and application thereof, and relates to the field of ocean energy storage. The battery comprises a negative electrode, a positive electrode, a diaphragm and an aqueous electrolyte, the negative electrode is metal cadmium or cadmium-based alloy; the active material of the positive electrode is metastable monoclinic phase vanadium dioxide; the diaphragm is a glass fiber diaphragm; the aqueous electrolyte is an aqueous solution containing cadmium salt; the total concentration of the cadmium salt in the aqueous electrolyte is 1-4 mol / L. The aqueous vanadium dioxide-cadmium metal secondary battery disclosed by the invention has the advantages of safe aqueous electrolyte system, high rate capability, ultra-long cycle life and the like, and has remarkable advantages when being applied to ocean energy storage.

The invention relates to the technical field of metallurgy and alloy materials, and discloses a low-carbon high-nitrogen vanadium-nitrogen alloy preparation method based on nitrogen increasing treatment, which comprises the following steps: uniformly mixing vanadium oxide, graphite powder and a catalytic nitrogen increasing agent according to a mass ratio of 1: (0.22-0.30): (0.01-0.05) to obtain a mixture, the catalytic nitrogen increasing agent is prepared by mechanically activating and nitriding ferrovanadium fine powder or ferrochromium fine powder and aluminum nitride powder in a nitrogen atmosphere; carrying out wet mixing activation and ball pressing on the mixture, and calcining in a nitrogen atmosphere to obtain a vanadium-nitrogen alloy; the vanadium-nitrogen alloy is ground into fine powder, the fine powder and iron oxide powder are mixed according to the proportion of 1: (0.05-0.1), secondary calcination is conducted under the CO2-NH3 composite atmosphere, and the low-carbon high-nitrogen vanadium-nitrogen alloy is obtained. According to the method, the problems that the iron catalyst of the vanadium-nitrogen alloy product is inactivated under the high-temperature condition, and the product is high in residual carbon and low in nitrogen due to the contradiction of the reaction conditions between high-temperature deoxidation and low-temperature nitriding are solved at the same time.

The present application relates to the technical field of dehydrogenation, in particular to a dehydrogenation catalyst, a preparation method and application thereof, and an alkane dehydrogenation method. The catalyst contains a carrier, chromium oxide, an auxiliary agent and a solid solution promoter supported on the carrier, the solid solution promoter is selected from one or more of gallium oxide, magnesium oxide and vanadium oxide; wherein the ratio of the central chromium content to the edge chromium content of the catalyst is 0.7-1.1. The catalyst of the present application is used for dehydrogenation reactions such as alkane dehydrogenation reactions, which can effectively reduce the occurrence of side reactions while ensuring high selectivity of the product, and improve the yield of by-product hydrogen.

The invention discloses a positive electrode lithium supplement agent and a preparation method and application thereof. The preparation method comprises the following steps: 1) mixing Li5FeO4 with sulfur powder and an oxygen absorbent to obtain a mixture; wherein the addition amount of the sulfur powder is 0.01-0.2% of the mass of the Li5FeO4; the addition amount of the oxygen absorbent is 0.5-3.0% of the mass of the Li5FeO4; the oxygen absorbent is one or more of nickel protoxide, manganese monoxide and vanadium monoxide; and 2) adding a binder into the mixture in the step 1), granulating in an inert atmosphere to obtain spherical precursor particles, and carbonizing and sintering the spherical precursor particles in the inert atmosphere to obtain the positive electrode lithium supplement agent.

The invention discloses a method for cleanly extracting vanadium from high-calcium vanadium slag of a converter. The method comprises the following steps: firstly, uniformly mixing the high-calcium vanadium slag with a magnesium sulfate solid and / or a solution containing magnesium sulfate, oxidizing and roasting at 500-700 DEG C for 30-60 minutes, heating to 850-900 DEG C, oxidizing and roasting for 30-90 minutes, cooling, and grinding to obtain a roasted material; carrying out primary acid leaching on the roasted material, and carrying out solid-liquid separation to obtain primary leachate and primary residues; ammonium sulfate is added into the primary leachate for high-temperature vanadium precipitation, ammonium polyvanadate and vanadium precipitation supernatant are obtained, and a vanadium oxide product is obtained after ammonium polyvanadate is calcined; the vanadium precipitation supernatant is mixed with the primary residues, secondary leaching is conducted, solid-liquid separation is conducted, and secondary leaching liquid and secondary residues are obtained; and finally, the secondary leaching solution can be used as an additive to be mixed and roasted with the high-calcium vanadium slag again for recycling. The process is simple and easy to implement, the leaching rate of vanadium and cleaning treatment of wastewater are improved by reasonably controlling the roasting conditions and recycling the secondary leachate, and the method has good environmental benefits and industrial application prospects.

Embodiments herein disclose a high-performance Vanadia-based catalyst designed for the efficient oxidation of sulfur dioxide (SO₂) to sulfur trioxide (SO₃) at significantly lower operating temperatures, with optimal performance around 400°C, a temperature lower than traditionally required by conventional catalysts. The catalyst consists of vanadium pentoxide (V₂O₅) as the active component, supported on naturally occurring uncalcined diatomaceous earth, combined with alkali metal promoters. A unique feature of the support material is the use of a mixture of relatively soft diatomaceous earth, exhibiting a percentage reduction of at least 35% in D50 particle size when measured by dry versus wet methods, alongside relatively hard diatomaceous earth to enhance mechanical strength. The catalyst demonstrates SO₂ conversion rates of 50-57% at 400°C and reaches a maximum of 80% at 410°C, surpassing benchmark catalysts that require higher temperatures (around 420°C) for similar conversions.

The invention relates to a preparation method of vanadium dioxide, and belongs to the technical field of chemical engineering. The preparation method comprises the following steps: calcining ammonium metavanadate to obtain vanadium pentoxide, adding the vanadium pentoxide and oxalic acid into a sulfuric acid solution, heating to 95-100 DEG C, reacting to obtain a tetravalent vanadium solution, cooling the tetravalent vanadium solution, adding ammonia water to adjust the pH value, reacting, cooling, precipitating, filtering and separating to obtain an intermediate product, namely vanadyl hydroxide, the method comprises the following steps: washing the vanadyl hydroxide with fresh water, filtering, and heating the vanadyl hydroxide to 500-600 DEG C to generate vanadium dioxide and water; the method is simple in process and small in pollution, the byproduct ammonia water in the process is recycled, the cost is saved, the finally obtained crystallized liquid is recycled for the next experiment, and secondary pollution is avoided.

The application provides a preparation method of a nitrogen-doped vanadium dioxide positive electrode active material, a positive electrode active material and a battery. The method comprises the following steps: mixing a vanadium source, lysine and water, and performing a hydrothermal reaction after adjusting pH. In the hydrothermal reaction process, the amino group in the lysine is used as a reducing agent to reduce the vanadium source into vanadium dioxide, and meanwhile, the nitrogen element in the lysine is doped into the vanadium dioxide crystal lattice in situ, so that the nitrogen-doped vanadium dioxide positive electrode active material is obtained. The method does not need to add a reducing agent and a nitrogen-containing polymer additionally, and does not need high-temperature calcination, so that the process is simplified, and energy consumption is reduced. The obtained material is uniformly doped with nitrogen, has good conductivity and cycle stability, and when the material is applied to an electrochemical device as a positive electrode active material, the material can provide stable capacity output and a long cycle life.

The invention provides a composite vanadium dioxide nano-particle as well as a preparation method and application thereof. The composite vanadium dioxide nano-particle comprises hollow spherical vanadium dioxide and a tin dioxide coating layer coating the surface of the hollow spherical vanadium dioxide, wherein in the composite vanadium dioxide nanoparticles, the weight content of the tin dioxide coating layer is 1-20%. According to the composite vanadium dioxide nano-particle provided by the invention, the hollow spherical vanadium dioxide is used as an inner core, the tin dioxide is used as a coating layer, and the content of the tin dioxide coating layer is further controlled, so that the obtained composite vanadium dioxide nano-particle has more excellent thermochromic performance, photosensitivity and oxidation resistance; further, the composite vanadium dioxide nano-particles can have a wider application scene in the field of thermochromic materials.

The application belongs to the field of phosphate inorganic material preparation, and relates to a method for preparing titanium-vanadium doped iron phosphate, which comprises the following steps: adding titanium and / or vanadium compounds into an iron phosphate complex solution to prepare an iron phosphate complex solution containing titanium and / or vanadium doped metal compounds, and then adding water into the mixed solution and heating to obtain titanium and / or vanadium ion doped iron phosphate; the titanium compound is selected from metatitanic acid, nano titanium dioxide, titanyl sulfate, titanyl oxalate, titanium citrate, titanium lactate or titanium tartrate; the vanadium compound is vanadium trioxide, vanadium dioxide (IV), vanadium pentoxide, vanadium monoxide, vanadium sulfate or vanadium trichloride. In addition, alternative solutions of adding sequence and adding timing change are provided. The application has simple process, is suitable for large-scale industrial production, and improves the electrochemical performance of lithium iron phosphate material in a power battery.

The invention belongs to the field of preparation of phosphate inorganic materials, and relates to a method for preparing titanium-vanadium doped iron phosphate, which comprises the following steps: adding a titanium and / or vanadium compound into an iron phosphate complex solution to prepare an iron phosphate complex solution containing a titanium and / or vanadium doped metal compound; adding water into the mixed solution, heating to obtain titanium and / or vanadium ion doped iron phosphate, and the titanium compound is selected from metatitanic acid, nano titanium dioxide, titanyl sulfate, titanyl oxalate, titanium citrate, titanium lactate or titanium tartrate; and the vanadium compound is vanadium trioxide, vanadium dioxide (IV), vanadium pentoxide, vanadium monoxide, vanadyl sulfate or vanadium trichloride. In addition, the invention also provides an alternative scheme for changing the adding sequence and the adding opportunity. The method is simple in process and suitable for large-scale industrial production, and the electrochemical performance of the power battery of the lithium iron phosphate material is improved.

The invention discloses a switchable metamaterial absorber based on vanadium dioxide and graphene and a dynamic tuning method, and relates to the technical field of terahertz wave devices. The absorber is formed by continuously splicing periodic unit structures on a plane in an array form, and each periodic unit structure is sequentially provided with a vanadium dioxide-graphene composite metasurface, a dielectric layer and a metal reflecting layer from top to bottom; the vanadium dioxide-graphene composite metasurface is composed of a patterned graphene disc and three fan-shaped structure vanadium dioxide layers distributed around the graphene disc in the circumferential direction, the insulation-metal phase change state of vanadium dioxide and the Fermi level of graphene are regulated and controlled through external excitation, and flexible switching between broadband absorption and double-narrow-band absorption can be achieved. The absorber has the advantages of being compact in structure, easy and convenient to prepare, insensitive to polarization and the like, has excellent dynamic tuning performance and wide-angle stability, and has integration and multifunctional application prospects in the fields of terahertz communication, imaging, biosensing, environment monitoring and the like.

The invention relates to the technical field of coatings, in particular to a multiband synergistic camouflage coating and a preparation method thereof. The invention discloses a multiband synergistic camouflage coating. The wave-absorbing coating is prepared from the following raw materials: acrylic acid modified polyurethane resin, polysilane modified epoxy resin, acrylic acid modified organic silicon resin, wave-absorbing particles, nano titanium dioxide, filler, activated boron nitride nanosheets, graphene oxide, hollow carbon microspheres, pyrrole monomers, an oxidizing agent, nano vanadium dioxide, a dispersing agent, a flatting agent, a defoaming agent, an anti-settling agent, extinction powder and trimethylolpropane tris [ 3-(2-methyl aziridinyl) propionate]. The obtained coating is good in wave absorbing effect, can realize multiband wave absorbing, has the function of reflecting solar radiation, is good in heat stability and scratch-resistant in paint film, and obviously enhances stealth stability; meanwhile, the process is simple and suitable for large-scale popularization and application.

The application discloses a highly-tunable vanadium dioxide nanowire sensor and a preparation method and application thereof, which comprises a substrate and electrodes, vanadium dioxide nanowires, fixed ends and power supply ends, a voltmeter and a sensitive layer on a resonator; two fixed ends are located on two electrodes of a source electrode and a drain electrode and are connected with two ends of the vanadium dioxide nanowires; the two electrodes of the source electrode and the drain electrode are connected with the vanadium dioxide nanowires and the two fixed ends on the substrate and support and fix one vanadium dioxide nanowire; the power supply end is connected with the electrode of the source electrode, and phase transition of the vanadium dioxide nanowire is caused by changing a circuit voltage so as to change a resonant frequency of the nanowire. The application forms an electric circuit on the vanadium dioxide nanowire, makes the two ends of the nanowire form a potential difference, causes the vanadium dioxide nanowire to gradually change phase by Joule heating, changes the resonant frequency of the nanowire, improves the sensitivity of the nanowire, and simultaneously detects gas molecules through the laid sensitive layer.

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.

This invention provides a nanozyme, its preparation method, and its application, belonging to the field of analytical chemistry detection technology. The nanozyme is vanadium oxide doped with a metal, in the form of nanoribbons. The metal is titanium, which is atomically loaded onto the vanadium oxide, with an atomic percentage of 1%-2%. The nanozyme of this invention possesses dual-enzyme activity similar to NADH oxidase and peroxidase. Utilizing its dual-enzyme activity in combination with natural enzymes, the amount of hydrogen peroxide is converted into a final measurement standard. Through the color change of a 3,3',5,5'-tetramethylbenzidine solution system, rapid qualitative and quantitative analysis of biomarkers for rare genetic metabolic diseases is achieved, providing a rapid, sensitive, and reliable colorimetric detection method.

The invention belongs to the technical field of electrochemical energy storage, and particularly relates to a poly-p-phenylenediamine / vanadium dioxide composite difunctional material as well as a preparation method and application thereof. The material takes poly-p-phenylenediamine coated vanadium dioxide as a core structure, p-phenylenediamine is subjected to in-situ polymerization through a hydrothermal reaction, and uniform coating of poly-p-phenylenediamine on the surface of vanadium dioxide is realized. The composite material can be used as a positive electrode of an aqueous zinc secondary battery, poly-p-phenylenediamine containing a specific functional group and vanadium dioxide can synergistically catalyze an iodine conversion reaction, meanwhile, the problem of irreversible vanadium dissolution of vanadium dioxide is effectively inhibited, and a vanadium-iodine dual-energy storage mechanism is successfully realized. The aqueous zinc battery based on the composite positive electrode is excellent in electrochemical performance, the specific capacity reaches up to 600 mAh / g under the current density of 1 A / g, the specific capacity of 440 mAh / g is still kept when the current density is increased to 10 A / g, and excellent rate capability is shown. And under the current density of 5 amperes / gram, the cycle life of 40000 circles is realized, which shows that the composite positive electrode has excellent cycle stability.

The invention discloses an indocyanine green photo-thermal heat-insulation energy-saving composite particle and a preparation method thereof. The preparation method comprises the following steps: firstly, carrying out amination treatment on the surfaces of vanadium dioxide nano particles so as to obtain aminated vanadium dioxide nano particles; then, the aminated vanadium dioxide nano particles and sulfonate particles of indocyanine green are subjected to a reaction, and the indocyanine green grafted vanadium dioxide nano particles are obtained. According to the invention, the defects of high phase change temperature, poor dispersity, poor stability under high-temperature and high-humidity conditions and the like of the traditional thermally induced phase change material vanadium dioxide are overcome. The prepared composite particles can realize phase change at a relatively low environment temperature, and have excellent dispersity and stability, and glass prepared from the composite particles has strong modulation capability on sunlight. In addition, the preparation method is simple and convenient in process and easy for large-scale production.

The application belongs to the technical field of composite functional materials, and provides a vanadium dioxide composite microcapsule, a preparation method and application thereof.The vanadium dioxide composite microcapsule comprises a core and a shell layer, the core is vanadium dioxide, the shell layer is a light-heat conversion material, and the light-heat conversion material is a transition metal compound or a high molecular polymer.The light-heat conversion material (a transition metal compound or a high molecular polymer) is used as the shell layer, the light-heat effect of the shell layer can convert solar energy into heat energy, induce local temperature rise, and drive vanadium dioxide to occur phase change under room temperature environment.Therefore, in the case that external temperature is insufficient to make vanadium dioxide occur phase change, the shell layer can convert light energy into heat energy, so that the temperature around vanadium dioxide reaches the phase change temperature, and phase change conversion is realized.