Preparation method and device of high-dispersity nano zirconium dioxide for hydrogen production by electrolysis of water

Abstract

The invention relates to the technical field of preparation of new zirconium oxide materials, and particularly discloses a preparation method and device of high-dispersity nano zirconium dioxide for hydrogen production through electrolysis of water, and the preparation method comprises the following steps: (S01) taking a proper amount of zirconium salt solution, and adjusting the pH value of the zirconium salt solution to 8-10; (S02) introducing the zirconium salt solution of which the pH is adjusted in the step (S01) into an electrolytic tank for ultrasonic treatment; (S03) carrying out sectional type heating electrolysis on the zirconium salt solution in the step (S02) through a bipolar electrode in an electrolytic tank; and (S04) collecting a product in the electrolytic tank after electrolysis in the step (S03) is finished, drying and calcining to obtain the nano zirconium dioxide. The method has the characteristics of being simple, good in nano particle dispersity and green.

Description

Technical Field

[0001] This invention relates to the field of zirconium oxide new material preparation technology, and in particular to a method and apparatus for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis. Background Technology

[0002] Conventional zirconium dioxide has a small specific surface area and underdeveloped porosity, which limits its performance and applications. Nano-zirconia overcomes these shortcomings. Nano-zirconia exhibits high chemical stability, resisting both chemical and microbial corrosion. It is a metal oxide with acidic, alkaline, oxidizing, and reducing properties. Its high melting point, high resistivity, high refractive index, and low coefficient of thermal expansion make it an important high-temperature resistant material and ceramic insulating material, showing broad application prospects in electronics, metallurgy, aerospace, chemical engineering, environmental science, biology, and medicine.

[0003] The preparation methods for nano-zirconia generally include physical and chemical methods. Physical methods mainly include spray-pyrolysis, sputtering, and plasma technology. Since physical methods are primarily used for preparing elemental and alloy nanoparticles, their application in actual production is limited; chemical methods are more commonly used. Currently, nano-zirconia prepared by chemical methods tends to agglomerate during preparation due to the high surface energy of the nanoparticles, resulting in increased particle size and poor regularity. Patent document CN108862379A discloses a method for preparing nano-zirconia. The method involves mixing a zirconium alkoxide mixture with ethylene glycol at a mass ratio of 1:1 to 2:1, adding 0.2 to 0.4 times the mass of the zirconium alkoxide mixture of modified nanofiber membrane and 0.01 to 0.02 times the mass of the zirconium alkoxide mixture of concentrated sulfuric acid, stirring the reaction, filtering, washing, and drying to obtain a nano-zirconia blank. The nano-zirconia blank is then calcined to obtain pretreated nano-zirconia. The pretreated nano-zirconia is then mixed with a sodium hydroxide solution at a mass ratio of 1:5 to 1:10, filtered, washed until the washing liquid is neutral, and dried to obtain nano-zirconia. The nano-zirconia exhibits a narrow particle size distribution, small size, excellent dispersibility, and is not prone to agglomeration during preparation. Although the patent mentions reducing agglomeration by adding modified nanofiber membranes and concentrated sulfuric acid, the actual mixing process of zirconium alkoxide mixtures and ethylene glycol requires precise control of the mass ratio and reaction conditions (such as temperature and stirring speed). This may be difficult to maintain in large-scale production, leading to agglomeration and resulting in unsatisfactory dispersion and regularity of nanoparticles. At the same time, the use of chemicals such as concentrated sulfuric acid may pose safety risks during the production process and have a certain impact on the environment. Therefore, corresponding safety and environmental protection measures need to be taken during the production process.

[0004] Therefore, the existing methods for preparing nano-zirconia have problems such as complex methods, nanoparticle dispersion, and lack of environmental friendliness. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems existing in the preparation process of nano-zirconia, the present invention provides a method and apparatus for preparing highly dispersed nano-zirconia for hydrogen production by electrolysis of water, which has the characteristics of simple method, good nanoparticle dispersion and greenness.

[0006] The first technical solution of the present invention: a method for preparing highly dispersible nano-zirconia for hydrogen production by electrolysis of water, comprising the following steps: (S01) taking an appropriate amount of zirconium salt solution and adjusting the pH value of the zirconium salt solution to 8-10; (S02) introducing the zirconium salt solution after pH adjustment in step (S01) into an electrolytic cell for ultrasonication; (S03) performing segmented heating electrolysis of the zirconium salt solution in step (S02) through bipolar electrodes in the electrolytic cell; (S04) collecting the product in the electrolytic cell after electrolysis in step (S03), drying and calcining it to obtain nano-zirconia. This invention adjusts the pH of the zirconium salt solution to an alkaline environment of 8-10, which effectively promotes the hydrolysis of zirconium salt into Zr(OH)4 colloid and avoids the introduction of impurities under acidic conditions. It employs ultrasonic-assisted electrolysis, where ultrasonic cavitation breaks up agglomerates, promoting uniform dispersion of the zirconium precursor and forming small-sized, narrowly distributed nanoparticles. A segmented heating electrolysis method is used, controlling the hydrolysis-condensation rate through a temperature gradient to avoid explosive nucleation, thereby improving crystallinity and dispersibility, ultimately yielding highly dispersed nanoparticles. This invention achieves one-step electrolytic synthesis of nano-zirconia, with hydrogen evolution at the cathode during electrolysis: 2H₂O + 2e⁻. - →H₂↑+2OH⁻, zirconium oxide salt is produced at the anode, Zr 4+ →ZrO2 can achieve the co-production of hydrogen energy and high-value-added nano-zirconium dioxide materials. Compared with the traditional sol-gel method, it can reduce washing and purification steps and reduce wastewater discharge. The nano-zirconium dioxide prepared by the method of this invention is simple and has green characteristics by coupling electrolytic hydrogen production with nano-zirconium dioxide synthesis.

[0007] Preferably, the zirconium salt solution in step (S01) is prepared by mixing zirconium salt with a deionized water solvent. Deionized water avoids impurity ions such as Ca. 2+ Mg 2+ Interfering with the hydrolysis process ensures the purity of the zirconium salt solution, is low-cost and environmentally friendly, and is suitable for industrial application.

[0008] Preferably, the zirconium salt in step (S01) is selected from one or more of zirconium sulfate or zirconium nitrate. The specific zirconium salt can be selected according to actual needs; zirconium sulfate and zirconium nitrate have moderate hydrolysis rates and are easy to control nucleation; when used in combination, the rapid nucleation performance of zirconium nitrate and the delayed aggregation performance of zirconium sulfate can be used to regulate the hydrolysis kinetics.

[0009] Preferably, the mass concentration of the zirconium salt solution in step (S01) is 45% to 70%. More preferably, the mass concentration of the zirconium salt solution in step (S01) is 50% to 65%. Even more preferably, the mass concentration of the zirconium salt solution in step (S01) is 55% to 60%. The defined mass concentration maintains electrolysis efficiency, sustains yield per unit volume, and reduces water treatment load; simultaneously, it balances subsequent electrolysis energy consumption, solution viscosity, and the dispersibility of the nano-zirconia particles.

[0010] Preferably, in step (S01), the pH value of the zirconium salt solution is adjusted by using a surface additive. The surface additive can adjust the pH value of the zirconium salt solution relatively gently.

[0011] Preferably, the surface additive is an amine-containing organic compound. The amine compound acts as both a mild alkaline pH adjuster and a complexing agent, reacting with Zr. 4+ It forms soluble complexes, which can slow down the hydrolysis rate and prevent explosive precipitation.

[0012] Preferably, the amine-containing organic compound is selected from one or more of ethylenediamine, triethylamine, and tetramethylethylenediamine. The amine-containing organic compound can be flexibly selected as needed, providing good controllability during pH adjustment.

[0013] Preferably, a dispersant and a stabilizer are added to the zirconium salt solution in step (S01). The addition of the dispersant allows it to adsorb onto the particle surface and prevents agglomeration through steric hindrance; the addition of the stabilizer provides electrostatic repulsion and maintains the stability of the colloid therein.

[0014] Preferably, the dispersant is selected from one or more of polyethylene glycol, polyvinyl alcohol, polymethyl methacrylate, or sodium polystyrene sulfonate. A variety of dispersants can be flexibly selected as needed, adsorbing onto the particle surface and effectively preventing agglomeration through steric hindrance.

[0015] Preferably, the stabilizer is a combination of sodium dodecyl sulfate and a polyelectrolyte. Sodium dodecyl sulfate provides good electrostatic repulsion; the polyelectrolyte can be polystyrene sulfonate, which enhances the stability of the colloid therein.

[0016] Preferably, the molar ratio of the dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 3–10:8–25:1. More preferably, the molar ratio of the dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 4–9:10–20:1. Even more preferably, the molar ratio of the dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 5–8:12–18:1. Even more preferably, the molar ratio of the dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 6–7:14–16:1. These defined molar ratios ensure that the dispersant adequately covers the particle surface, the stabilizer effectively maintains the electric double layer structure in the solution, and maintains a balance between good dispersibility and prevention of flocculation.

[0017] Preferably, the zirconium salt solution to be introduced into the electrolytic cell in step (S01) is centrifuged to obtain the supernatant, and the supernatant is then introduced into the electrolytic cell in step (S02). Centrifugation can effectively remove undissolved zirconium salt aggregates or impurities, ensuring the homogeneity of the electrolytic precursor solution.

[0018] Preferably, the centrifugation speed is 3000 rpm to 5000 rpm. More preferably, the centrifugation speed is 3500 rpm to 4500 rpm. Even more preferably, the centrifugation speed is 4000 rpm. The limited centrifugation speed balances separation efficiency and time cost, avoiding colloid damage caused by excessively high speeds.

[0019] Preferably, the ultrasonic frequency in step (S02) is 20 kHz to 40 kHz. More preferably, the ultrasonic frequency in step (S02) is 25 kHz to 35 kHz. Even more preferably, the ultrasonic frequency in step (S02) is 30 kHz. The defined ultrasonic frequency can generate stable cavitation bubbles, effectively breaking up zirconium precursor agglomerates; the defined ultrasonic frequency can also enhance solution mass transfer, accelerate the migration of Zr4+ to the electrode surface, improve electrolysis efficiency, avoid the deposition of electrolysis products, such as Zr(OH)4, on the electrode surface, and maintain the exposure of active sites.

[0020] Preferably, the ultrasonic time in step (S02) is 25 min to 45 min. More preferably, the ultrasonic time in step (S02) is 30 min to 40 min. Even more preferably, the ultrasonic time in step (S02) is 35 min. The limited ultrasonic time ensures sufficient dispersion of the zirconium precursor while avoiding secondary agglomeration of particles due to excessive ultrasonication, thus balancing dispersion completeness, energy consumption, and nanoparticle stability. The cavitation effect of ultrasonic frequency and ultrasonic time acts uniformly on the entire solution, rather than locally. The synergistic time of electrolysis and ultrasonication is sufficient to generate a highly dispersed ZrO2 precursor, resulting in nano-ZrO2 with a narrow particle size distribution of 20–50 nm and no hard agglomeration, suitable for catalytic or coating applications.

[0021] Preferably, the zirconium salt solution after ultrasonication in step (S02) is pretreated, including the following steps: (S02-A1) adding an appropriate amount of complexing agent to the zirconium salt solution and mixing thoroughly with a stirrer; (S02-A2) passing the mixed zirconium salt solution from step (S02-A1) through a filter membrane to remove insoluble matter and impurities. The addition of the complexing agent stabilizes zirconium ions and inhibits premature hydrolysis; the complexing agent can form stable soluble complexes with Zr4+, slowing down the hydrolysis rate and avoiding explosive nucleation caused by local supersaturation, thereby improving the monodispersity of nanoparticles; the complexed Zr4+ is gradually released during electrolysis, ensuring uniform reaction on the electrode surface and reducing dendrite or large particle deposition; the complexing agent can also bind trace metal impurities in the solution, such as Fe. 3+ Alternatively, Ca2+ can be used to avoid co-precipitation affecting product purity; removing insoluble matter and impurities through a filter membrane can improve precursor purity, remove undissolved zirconium salt aggregates, mechanical impurities, or complex precipitates, such as Zr-EDTA, to ensure the homogeneity of the electrolytic precursor solution and prevent particulate matter from clogging electrode pores or scratching the electrode surface; ultrasonically breaking up agglomerates → stabilizing monodisperse ions with a complexing agent → filtering out residual impurities forms a complete pretreatment chain, ensuring that the final electrolytic product has a more uniform particle size and no hard agglomerates after calcination.

[0022] Preferably, the complexing agent in step (S02-A1) is selected from one or more of ethylenediaminetetraacetic acid, aminotriacetic acid, or diethylenetriaminepentaacetic acid. The type of complexing agent can be flexibly selected according to actual needs, all of which have good chelating ability and can effectively control the hydrolysis effect.

[0023] Preferably, the amount of complexing agent added is 0.1% to 1% of the total volume of the zirconium salt solution. More preferably, the amount of complexing agent added is 0.2% to 0.9% of the total volume of the zirconium salt solution. More preferably, the amount of complexing agent added is 0.3% to 0.8% of the total volume of the zirconium salt solution. More preferably, the amount of complexing agent added is 0.4% to 0.7% of the total volume of the zirconium salt solution. More preferably, the amount of complexing agent added is 0.5% to 0.6% of the total volume of the zirconium salt solution. Limiting the amount of complexing agent added ensures sufficient complexation, maintains good hydrolysis, and avoids excessive inhibition of hydrolysis, ensuring good electrolysis efficiency and electrolysis cost, balancing the complexation effect and economy, and is suitable for industrialization.

[0024] Preferably, the pore size of the filter membrane in step (S02-A2) is 0.15 μm to 0.35 μm. More preferably, the pore size of the filter membrane in step (S02-A2) is 0.17 μm to 0.33 μm. More preferably, the pore size of the filter membrane in step (S02-A2) is 0.2 μm to 0.3 μm. More preferably, the pore size of the filter membrane in step (S02-A2) is 0.22 μm to 0.28 μm. More preferably, the pore size of the filter membrane in step (S02-A2) is 0.24 μm to 0.26 μm. The defined filter membrane pore size balances efficiency and throughput; the filtration time should be performed immediately after mixing the complexing agent to prevent decomposition of the complex due to standing; the filtration is pressure filtration.

[0025] Preferably, the electrolyte preparation in step (S02) of the electrolytic cell includes the following steps: (S02-B1) preparing an initial electrolyte containing deionized water and a buffer in the electrolytic cell; (S02-B2) adding an appropriate amount of electrolyte to the initial electrolyte in step (S02-B1); (S02-B3) adding a conductivity enhancer equivalent to 20% to 50% of the amount of buffer added to the electrolyte in step (S02-B2); (S02-B4) adding a surfactant equivalent to 1% to 3% of the amount of buffer added to the electrolyte in step (S02-B3), and mixing thoroughly using a stirrer. The initial electrolyte, made from deionized water and a buffer, effectively balances buffering capacity and solution viscosity, preventing deposition on the electrode surface. The addition of electrolyte improves electrolyte conductivity, reduces energy consumption, and adapts to the stable current distribution of the bipolar electrode. A limited amount of conductivity enhancer further enhances electrolyte conductivity. A limited amount of surfactant effectively regulates the interface, such as reducing surface tension, promoting bubble detachment from the electrode, reducing polarization, inhibiting particle aggregation, and improving the dispersibility of nano-ZrO2. A limited amount of surfactant can form a monolayer coating, avoiding excessive foaming or hindering electrolysis.

[0026] Preferably, the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 45% to 70%. More preferably, the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 50% to 65%. Even more preferably, the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 55% to 60%. The defined buffer mass concentration can effectively balance buffering capacity and solution viscosity, and also avoids excessively high concentrations that inhibit ion migration.

[0027] Preferably, the buffer in step (S02-B1) is sodium dihydrogen phosphate. Sodium dihydrogen phosphate is nearly neutral to weakly acidic, which can match the pH requirements of zirconium salt electrolysis. It has both buffering and scale inhibition functions, and can prevent deposits on the electrode surface.

[0028] Preferably, the conductivity enhancer in steps (S02-B3) is selected from one or more of potassium nitrate or potassium sulfate. The type of conductivity enhancer can be selected according to actual needs, which can further enhance the conductivity of the electrolyte.

[0029] Preferably, the surfactant in step (S02-B4) is selected from one or more of sodium dodecyl sulfate, polysorbate, or octylbenzyl alcohol. The type of surfactant can be selected according to actual needs. Sodium dodecyl sulfate can reduce surface tension, promote the detachment of bubbles such as H2 / O2 from the electrode, and reduce polarization. Polysorbate and octylbenzyl alcohol can inhibit particle agglomeration and improve the dispersibility of nano ZrO2.

[0030] Preferably, the electrolyte in the electrolytic cell of step (S02) is selected from sodium sulfate or potassium nitrate, or a mixture of both. The type of electrolyte can be selected according to actual needs; wherein, sodium sulfate contains SO42-. 2 - It is stable at the anode, does not oxidize to produce harmful gases, has good safety, has a wide pH adaptability, is well compatible with the pH of zirconium salt hydrolysis, has low corrosivity, and does not damage the electrode; potassium nitrate has high solubility, can provide higher conductivity, reduce cell voltage, and save energy; the selected electrolytes are all inert electrolytes, which are environmentally friendly.

[0031] Preferably, the molar ratio of zirconium ions to electrolyte in the electrolytic cell of step (S02) is 1:0.1 to 0.3. More preferably, the molar ratio of zirconium ions to electrolyte in the electrolytic cell of step (S02) is 1:0.2. This defined molar ratio ensures sufficient electrolyte, high solution conductivity, and stable electrolysis efficiency. It also prevents competitive adsorption on the electrode surface due to excess electrolyte, thus preventing the directional deposition of Zr⁴⁺. Furthermore, it balances conductivity and zirconium ion migration efficiency, ensuring that the electrolysis reaction is dominated by Zr⁴⁺, resulting in good economic efficiency and avoiding electrolyte waste.

[0032] Preferably, the electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 3-5 volts, current density 20 mA / cm². 2 ~50mA / cm 2 More preferably, the electrolysis conditions of the electrolytic cell in step (S03) are preset to an initial voltage of 3.5–4.5 volts and a current density of 30 mA / cm². 2 ~40mA / cm 2 More preferably, the electrolysis conditions of the electrolytic cell in step (S03) are preset to an initial voltage of 4 volts and a current density of 35 mA / cm². 2The limited initial voltage ensures the oxidation potential of Zr4+ / ZrO2, meets the requirements for the superposition of oxygen evolution potentials, avoids reaction stagnation, and prevents side reactions such as anodic corrosion and electrolyte decomposition caused by excessive voltage. It balances the reaction rate and energy consumption, achieving efficient oxidation of Zr4+ while avoiding excessive oxygen evolution: 2H2O → O2↑ + 4H + +4e - This avoids wasting electrical energy; the limited current density ensures reaction kinetics, preventing excessively low nucleation rates that lead to coarse particles, and also prevents excessively high currents that could cause concentration polarization or hydroxide ion competition reactions. While achieving a high deposition rate, it can maintain uniform ion mass transfer, generating nano-ZrO2 with a narrow particle size distribution of 30–50 nm; voltage and current density matching ensures that the Zr4+ oxidation rate is synchronized with ion migration; heating compensates for the electrolytic heat effect, maintaining the stability of the reaction system.

[0033] Preferably, the segmented heating electrolysis temperature range in step (S03) is 25℃ to 45℃. This defined segmented heating electrolysis temperature range effectively controls the nucleation rate, stabilizes crystal growth, promotes the formation of dense ZrO2, avoids particle agglomeration caused by high temperatures, and improves the crystallinity and dispersibility of the product.

[0034] Preferably, the segmented heating in step (S03) is as follows: (S03-1) Before starting electrolysis, the temperature of the electrolyte in the electrolytic cell is adjusted to 25°C; (S03-2) The electrolyte temperature in step (S03-1) is gradually increased to 35°C at a rate of 0.5°C to 2.5°C per minute; (S03-3) When the electrolyte reaches the first stage temperature of 35°C, the first stage temperature is maintained and electrolysis continues for 10 to 15 minutes; (S03-4) After the electrolysis in step (S03-3) is completed, the electrolyte temperature is further increased to the final working temperature of 45°C at a rate of 0.5°C to 2.5°C per minute; (S03-5) The electrolyte that has reached the final working temperature in step (S03-4) continues to be electrolyzed for 30 to 80 minutes. The low-temperature environment of 25℃ slows down the hydrolysis and nucleation rate of zirconium ions, which is conducive to the formation of fine and uniform crystal nuclei and avoids explosive agglomeration. At 25℃, electrode side reactions, such as oxygen and hydrogen evolution, have a lower rate, which reduces gas interference and improves current efficiency. Gradually increasing the temperature to 35℃ at a rate of 0.5℃ to 2.5℃ per minute, preferably 1℃ / min, allows the crystal nuclei to grow gradually, avoiding particle coarsening caused by sudden temperature increases. This balances reaction kinetics, and the slow heating accelerates the hydrolysis and deposition of Zr⁴⁺, avoiding local concentration gradients caused by excessively rapid temperature changes. When 35℃ is reached, continuous electrolysis for 10–15 minutes effectively stabilizes the crystal structure. 35℃ is the critical temperature range for the transformation of Zr(OH)₄ to ZrO₂. The isothermal stage ensures the amorphous precursor fully transforms into the tetragonal or monoclinic phase, and maintaining the temperature synchronizes particle growth, reducing particle size. The electrolyte temperature is continuously increased at a rate of 0.5℃ to 2.5℃ per minute until it reaches 45℃. Heating to 45℃ accelerates Ostwald ripening of the particles, fills pores, increases product density, improves ion mobility, reduces electrolysis energy consumption, and optimizes electrolysis efficiency. Maintaining the electrolysis process at the final operating temperature for 30 to 80 minutes ensures proper crystallization and purification. 30 to 55 minutes is suitable for thin-layer deposition in coating applications, while 56 to 80 minutes is suitable for high-crystallinity ZrO2 in catalyst support applications, and also removes organic residues. High-temperature electrolysis decomposes residual complexing agents or surfactants, reducing the calcination burden. The temperature-time synergy, with a segmented design of 25℃→35℃→45℃, matches the entire process of nucleation-growth-densification, superior to single-temperature zone electrolysis. The expected product size is 30–50 nm, with a specific surface area ≥80 m². 2 / g, monoclinic or tetragonal phase is controllable.

[0035] Preferably, the drying in step (S04) is vacuum drying or freeze drying. There are two drying methods to choose from: vacuum drying is gentler and more energy-efficient; freeze drying can protect the structure and maintain high porosity.

[0036] Preferably, the vacuum drying temperature is 50℃ to 70℃. More preferably, the vacuum drying temperature is 55℃ to 65℃. Even more preferably, the vacuum drying temperature is 60℃. The defined vacuum drying temperature is relatively mild, and the low-temperature, reduced-pressure environment avoids particle agglomeration, thus preserving a high specific surface area >80m². 2 / g.

[0037] Preferably, the vacuum drying time is 8h to 16h. More preferably, the vacuum drying time is 10h to 14h. Even more preferably, the vacuum drying time is 11h to 13h. Even more preferably, the vacuum drying time is 12h. The limited vacuum drying time is energy-efficient and effective, removing most of the free water within a limited time, shortening the time by 30% compared to atmospheric pressure drying.

[0038] Preferably, the freeze-drying temperature is -60℃ to -40℃. More preferably, the freeze-drying temperature is -55℃ to -45℃. Even more preferably, the freeze-drying temperature is -50℃. The defined freeze-drying temperature provides structural protection, prevents particle collapse caused by capillary forces during ice crystal sublimation, and the porous structure of the product is beneficial for catalytic or support applications.

[0039] Preferably, the freeze-drying time is 12h to 36h. More preferably, the freeze-drying time is 16h to 32h. Even more preferably, the freeze-drying time is 20h to 28h. Even more preferably, the freeze-drying time is 24h. The limited freeze-drying time can sufficiently remove most of the free water.

[0040] Preferably, the calcination temperature in step (S04) is 300℃ to 700℃. More preferably, the calcination temperature in step (S04) is 350℃ to 650℃. More preferably, the calcination temperature in step (S04) is 400℃ to 600℃. More preferably, the calcination temperature in step (S04) is 450℃ to 550℃. More preferably, the calcination temperature in step (S04) is 500℃. The low-temperature range of 300℃ to 400℃ effectively removes organic matter; the medium-temperature range of 400℃ to 600℃ balances crystallinity and particle size control, generating tetragonal ZrO2 and avoiding monoclinic phase transformation and particle sintering caused by high temperatures; the high-temperature range of 600℃ to 700℃ is suitable for bulk materials requiring high mechanical strength, and the calcination temperature can be controlled according to actual needs.

[0041] Preferably, the calcination time in step (S04) is 2h to 4h. More preferably, the calcination time in step (S04) is 2.5h to 3.5h. Even more preferably, the calcination time in step (S04) is 3h. The limited calcination time ensures complete decomposition of organic matter while avoiding excessive grain growth due to prolonged calcination.

[0042] Preferably, the average particle size of the nano-zirconia in step (S04) is 10–50 nm. More preferably, the average particle size of the nano-zirconia in step (S04) is 15–45 nm. More preferably, the average particle size of the nano-zirconia in step (S04) is 20–40 nm. More preferably, the average particle size of the nano-zirconia in step (S04) is 25–35 nm. More preferably, the average particle size of the nano-zirconia in step (S04) is 30 nm. The defined average particle size provides a higher specific surface area, which enhances catalytic activity; the dielectric properties are also relatively good, falling within the particle size range that reduces grain boundary defects and lowers dielectric loss.

[0043] Preferably, in step (S04), the dielectric constant of nano-zirconia at 20 kHz is 38–42, and the electrical loss tangent is 0.0015–0.0025.

[0044] Preferably, in step (S04), the dielectric constant of nano-zirconia at 25 kHz is 39–43, and the electrical loss tangent is 0.0014–0.0019.

[0045] Preferably, in step (S04), the dielectric constant of the nano-zirconia at 30 kHz is 40–44, and the electrical loss tangent is 0.0013–0.0017. This defined dielectric constant range matches the requirements of high-frequency electronic devices; the defined electrical loss tangent range ensures pure grain boundaries and an impurity content of <0.1%.

[0046] Preferably, in step (S04), the product collected in the electrolytic cell is washed through a ceramic membrane. The ceramic membrane can efficiently purify the product and remove SO4. 2- The presence of residual K+ electrolyte ensures a purity >99.5% and protects the particle structure, avoiding mechanical shear damage to nanoparticles compared to centrifugal washing. The ceramic membrane can be an Al2O3 membrane with a pore size of 0.05μm–0.2μm, more preferably an Al2O3 membrane with a pore size of 0.1μm–0.15μm. Freeze-drying at -50℃ for 24h followed by calcination at 500℃ for 3h (N2 atmosphere for oxidation prevention) yields high-purity tetragonal ZrO2 with a pore size of 30nm and the lowest dielectric loss. Vacuum drying at 60℃ for 12h followed by calcination at 550℃ for 3h is suitable for low-cost industrial mass production, but requires a slightly larger particle size of around 40nm.

[0047] The second technical solution of the present invention: a device for preparing highly dispersible nano-zirconia for hydrogen production by electrolysis of water, comprising a frame, wherein a solvent mixing cylinder and an electrolysis chamber are provided on the frame; the solvent mixing cylinder is connected to the electrolysis chamber through a solution delivery mechanism; an ultrasonic generator is provided inside the solvent mixing cylinder; an electrolysis cell is provided inside the electrolysis chamber, and the solvent mixing cylinder is connected to the electrolysis cell through the solution delivery mechanism; a bipolar electrode is provided at the bottom of the electrolysis cell; the bipolar electrode comprises an electrode body, wherein a first electrode segment and a second electrode segment are connected to the electrode body through conductive connectors, and the first electrode segment and the second electrode segment are correspondingly inserted into the anode chamber and cathode chamber of the electrolysis cell. The present invention integrates a solvent mixing cylinder and an electrolysis chamber on a frame, reducing the equipment footprint and facilitating assembly line operation. The rigid frame also reduces vibration interference and ensures the stability of the electrolysis process. The frame can be made of 304 stainless steel. The zirconium salt solution is directly ultrasonically treated within the solvent mixing cylinder, avoiding secondary contamination or agglomeration caused by transfer. Ultrasonic cavitation also effectively promotes the uniform mixing of zirconium salt with complexing agents, dispersants, and other additives, improving the homogeneity of the precursor solution. The solution delivery mechanism in this invention precisely introduces the mixed solution into the electrolysis cell via a pump or gravity flow, enabling controllable delivery and avoiding [missing information - likely a continuation of the previous sentence]. To eliminate manual operation errors, the solution delivery mechanism is equipped with a corrosion-resistant peristaltic pump on the adjustment and delivery pipeline. The pipeline uses PTFE piping to effectively prevent metal ion contamination of the delivered solution. The solution delivery process employs a relatively closed system, minimizing air contact and preventing Zr⁴⁺ hydrolysis or the introduction of impurities. A bipolar electrode structure is incorporated, reducing energy consumption by approximately 15% compared to traditional unipolar electrolysis. The first electrode section corresponds to the anode chamber of the electrolytic cell, oxidizing Zr⁴⁺ to ZrO₂ while simultaneously releasing oxygen: 4OH⁻ → O₂↑ + 2H₂O + 4e⁻. - The second electrode section corresponds to the cathode chamber of the electrolytic cell, where H2O is reduced to produce hydrogen: 2H2O + 2e- - →H2↑+2OH-, enabling co-production of hydrogen and zirconium; conductive connectors ensure a stable potential difference between the two electrode sections, preventing uneven current distribution; the anode and cathode chambers within the electrolytic cell are partitioned to prevent H2 from entering the anode area and affecting ZrO2 purity, avoiding cross-contamination of products; the invention employs an ultrasonic solvent mixing → bipolar electrode electrolysis → product collection process, which is fully enclosed and controllable, suitable for continuous production; the byproduct OH- from water electrolysis for hydrogen production can be recycled for pH adjustment, enabling resource utilization; a pH sensor and a viscometer are installed in the solvent mixing cylinder, and pH, temperature, and current sensors are installed in each electrolysis chamber.

[0048] Preferably, a stirring component is rotatably mounted inside the solvent mixing cylinder, and a stirring motor is mounted outside the solvent mixing cylinder. The drive end of the stirring motor is connected to the stirring component. The stirring component includes a stirring shaft, which is rotatably mounted inside the solvent mixing cylinder. One end of the stirring shaft is connected to the drive end of the stirring motor via a coupling, and the end of the stirring shaft away from the stirring motor is rotatably mounted on the solvent mixing cylinder via a sealed bearing. Multiple sets of first and second electric telescopic rods are distributed along the axial direction of the stirring shaft. The stirring motor drives the stirring shaft to rotate, and the telescopic action of the electric telescopic rods achieves three-dimensional stirring, avoiding solution stratification or localized uneven concentration, and achieving efficient mixing. A sealed bearing made of PTFE is installed at the rotatable connection between the stirring shaft and the solvent mixing cylinder.

[0049] Preferably, the first and second electric telescopic rods in each group are arranged in a cross-shaped staggered configuration. This cross-shaped layout can create turbulence, enhance the mechanical breaking up of zirconium salt agglomerates, and improve dispersibility; it can also ensure mixing throughout the cylinder, especially for high-concentration solutions, such as 60% Zr salt, where the stirring performance is better.

[0050] Preferably, the solvent mixing cylinder is equipped with an inner spiral guide plate and an outer spiral guide plate, which together form a double spiral structure. The inner spiral guide plate is sequentially connected to the middle of the first and second electric telescopic rods along the axial direction of the stirring shaft; the outer spiral guide plate is sequentially connected to the ends of the first and second electric telescopic rods along the axial direction of the stirring shaft. The double spiral structure formed by the inner and outer spiral guide plates creates a composite axial and radial flow field within the cylinder, accelerating the diffusion of additives. The spiral plates convert rotational kinetic energy into laminar shear force, reducing motor power consumption.

[0051] Preferably, the solvent mixing cylinder is provided with a transparent observation window for monitoring the mixing process of the zirconium salt solution. The transparent observation window is made of high borosilicate glass, which allows for direct observation of the solution mixing state, such as whether it is uniform and whether there is any precipitation. This facilitates timely adjustment of parameters and avoids fluctuations in the performance of subsequent electrolysis products due to uneven mixing.

[0052] Preferably, the solvent mixing cylinder is provided with an inlet and an outlet, and the outlet is connected to the electrolysis chamber through a solution conveying mechanism. The inlet is located at the top of the solvent mixing cylinder, and the outlet is located at the bottom of the solvent mixing cylinder. The inlet can be connected to an automatic feeder, and the outlet is conveyed by a peristaltic pump to achieve continuous production, which can appropriately reduce manual intervention. A 90-110 mesh, preferably 95-105 mesh, and more preferably 100 mesh screen is installed at the outlet to effectively prevent undissolved particles from entering the electrolysis cell.

[0053] Preferably, the solvent mixing cylinder has multiple reactant storage chambers on its outer wall, each corresponding to a first and second electrically operated telescopic rod in a corresponding group. The reactant storage chambers are linked to the electrically operated telescopic rods, allowing for the release of pH adjusters or dispersants as needed during stirring, achieving precise dosing and improving mixing efficiency. Reagents can be added without interrupting stirring, reducing downtime and making it suitable for continuous production.

[0054] Preferably, a reactant adding cylinder is threadedly connected to the reactant storage chamber; the interior of the reactant adding cylinder is divided into an upper inner cavity and a lower inner cavity by an openable and closable partition, and the lower inner cavity is connected to the interior of the solvent mixing cylinder. The threaded connection facilitates quick replacement or replenishment of reactants such as pH adjusters and dispersants, reduces downtime, and prevents air or moisture from seeping in and causing reagent deterioration; a PTFE sealing ring is installed at the threaded connection.

[0055] Preferably, the separating component includes a flexible separating layer, which is elastically disposed on the inner wall surface of the reactant adding cylinder. When the flexible separating layer flexibly contracts, its edges adhere to the inner wall surface of the reactant adding cylinder; when the flexible separating layer flexibly expands, a gap is formed between the edges of the flexible separating layer and the inner wall surface of the reactant adding cylinder. The flexible separating layer can control the reagent flow rate through contraction and expansion, achieving precise addition, such as controlling the dropping rate of pH adjuster to 0.1 mL / s; the elastic closure design also prevents the mixed solution from backflowing and contaminating the reactant storage chamber.

[0056] Preferably, the reactant adding cylinder is equipped with an umbrella-shaped support frame. The open side of the umbrella-shaped support frame is attached to the bottom of the flexible partition layer, and the side of the umbrella-shaped support frame away from the flexible partition layer corresponds to the telescopic ends of the first and second electric telescopic rods in the corresponding group of the reactant adding cylinder. The linkage design between the reactant adding system and the stirring component has a high level of automation, and the stroke of the electric telescopic rod and the opening and closing of the umbrella-shaped support frame are controlled by PLC logic.

[0057] Preferably, the umbrella-shaped expansion frame includes a bearing seat at the bottom of the reactant adding cylinder. A support main shaft is telescopically mounted on the bearing seat. One end of the support main shaft is attached to the central area of ​​the flexible partition layer, and the other end of the support main shaft, away from the flexible partition layer, extends through the reactant adding cylinder and into the solvent mixing cylinder. The other end of the support main shaft, away from the flexible partition layer, corresponds to the telescopic ends of the first and second electric telescopic rods in the corresponding group of the reactant adding cylinder. The telescopic movement of the electric telescopic rods is transmitted through the support main shaft, driving the umbrella-shaped frame to open the flexible partition layer, achieving automated addition. It has a good mechanical linkage effect, and the reactant release rate matches the stirring intensity. The addition amount will also increase accordingly at high speeds. The docking accuracy between the support main shaft and the electric telescopic rods is ≤0.1mm.

[0058] Preferably, the main shaft of the support is radially connected with at least three inclined support rods. A steel ball roller is movably mounted on the end of each inclined support rod away from the main shaft. The inner wall of the reactant addition cylinder has at least three arc-shaped grooves, and the rolling seal of the steel ball roller is disposed within the corresponding arc-shaped groove. Perfluoropolyether oil is added to the rolling area between the steel ball roller and the arc-shaped groove.

[0059] Preferably, the inclined support rod is inclined downward relative to the horizontal plane, and the downward inclination angle of the inclined support rod is 2 degrees to 10 degrees. More preferably, the downward inclination angle of the inclined support rod is 4 degrees to 8 degrees. Even more preferably, the downward inclination angle of the inclined support rod is 5 degrees to 7 degrees. The downward inclination angle allows residual reagents to flow back naturally, avoiding accumulation; the limited inclination angle balances support force and flowability, preventing excessive deformation of the flexible separator layer.

[0060] Preferably, both sides of the inclined support rod are hinged with partition plates, and the partition plates between the two inclined support rods are fitted and sealed together, with the partition plates close to the flexible partition layer; a plurality of partition surface pushers are rotatably connected to the shaft seat, and the partition surface pushers are rotatably connected to the corresponding partition plates.

[0061] Preferably, the separating surface pusher includes a plurality of first ear plates arranged circumferentially along the shaft seat, and a support arm is rotatably connected to the first ear plate; the bottom of the separating layer plate is provided with a second ear plate, and the second ear plate is rotatably connected to the end of the corresponding support arm away from the shaft seat.

[0062] Preferably, the separator plate is a fan-shaped plate. When the separator plate is not opened, adjacent separator plates and the separator plate and its corresponding support rod are sealed together. The fan-shaped separator plate is completely sealed when closed and forms a uniform channel when open, which can avoid local blockage during additive addition. The support arm is hinged by an ear plate to achieve synchronous opening and closing, ensuring uniform release of reagents. The overall design is similar to a petal-shaped valve, which has a good additive addition effect.

[0063] Preferably, the flexible separator layer is made of a chemically resistant flexible material. Fluororubber or silicone, such as PTFE-coated silicone, can be used. These materials offer good resistance to corrosion from reagents such as zirconium salts or organic amines, have a long service life, reduce the frequency of subsequent maintenance, and are suitable for continuous production.

[0064] Preferably, the electrolytic cell has a transparent window at the top. The transparent window is made of borosilicate glass, which allows for real-time observation of the electrolysis status, such as bubble precipitation and electrode deposition, enabling timely adjustment of parameters. In case of abnormalities, such as electrode corrosion or solution discoloration, the electrolytic cell can be shut down immediately. The side of the transparent window located inside the electrolytic cell is coated with an anti-corrosion film.

[0065] Preferably, the upper half of the electrode body is covered with an insulating layer, and a portion of the outer edge of the electrode body protrudes beyond the insulating layer. The surface of this protruding portion of the electrode body is coated with a functional coating. This partial exposure design, where only the protruding portion of the electrode body is coated with the functional coating, reduces the amount of precious metals used, thus lowering costs. Furthermore, the insulating layer and the functional coating balance insulation protection and catalytic activity.

[0066] Preferably, the insulating layer is made of a mixture of a polymer-based composite material and an inorganic filler. The polymer-based composite material can be PTFE, which provides chemical inertness, while the inorganic filler can be Al2O3, which enhances mechanical strength, resulting in an insulating layer with good insulation properties and strength. The content of the inorganic filler in the insulating layer is 20%–40%; more preferably, the content is 25%–35%.

[0067] Preferably, the functional coating is made of a composite material of carbon nanotubes or graphene oxide and platinum or palladium nanoparticles. The high specific surface area of ​​carbon materials supporting Pt / Pd nanoparticles exhibits high catalytic activity and can effectively improve hydrogen evolution or oxygen evolution efficiency; graphene has better oxidation resistance than traditional carbon supports, which can extend the coating life.

[0068] Preferably, a TiN transition layer is added between the electrode body and the functional coating. This effectively prevents the functional coating from peeling off.

[0069] Preferably, the electrode body has a rectangular structure, and the upper surface of the electrode body is provided with conical guide surfaces on all four sides. The conical guide surfaces are composed of two long-side guide surfaces and two short-side guide surfaces. A first groove surface is formed in the middle of the short-side guide surface. The first groove surface adopts a trapezoidal surface structure that is narrower at the top and wider at the bottom. Second groove surfaces are provided at both ends of the long-side guide surfaces. The second groove surfaces adopt a fan-shaped curved surface structure that is narrower at the top and wider at the bottom. The long-side and short-side guide surfaces can optimize the electrolyte flow, reduce bubble retention, and improve the current efficiency by 10% to 15%. The trapezoidal first groove surface structure guides the merging of small bubbles, and the fan-shaped curved second groove surface structure promotes the detachment of large bubbles, reduces electrode polarization loss, and allows bubbles to be released quickly. The groove structure also increases the actual reaction area by 20% to 30%. The conical guide surfaces and groove catalysts can synergistically optimize bubble management and reaction dynamics.

[0070] Preferably, both the first and second groove surfaces are coated with a catalyst layer. Increasing the thickness of the catalyst layer in the grooves where bubbles are prone to stagnation can specifically enhance catalytic activity.

[0071] Preferably, the catalyst layer is made of carbon nanotube material, graphene oxide material, platinum metal nanomaterial, palladium metal nanomaterial, or nickel-iron layered bimetallic hydroxide NiFe-LDH.

[0072] Preferably, the first electrode segment is made of a mixture of nickel foam and fluorine-doped tin oxide, or it is made of titanium mesh (Ti plated with platinum (Pt) or iridium-plated (Ir) material. Nickel foam has high porosity, which promotes gas diffusion and electrolyte penetration, and its resistivity is ≤10 Ω·cm. -6 The Ω·m value reduces ohmic losses. Fluorine-doped tin oxide exhibits good stability in alkaline environments and can form heterojunctions with nickel foam, enhancing electron transfer rates. Titanium possesses excellent corrosion resistance and is a good Pt / Ir catalyst, exhibiting high activity and long lifespan. It can efficiently oxidize Zr⁴⁺ to ZrO₂ while simultaneously undergoing the oxygen evolution reaction, and also shows good resistance to corrosion from high potentials and acidic / alkaline electrolytes.

[0073] Preferably, the second electrode section is made of nickel foam (Ni), nickel mesh, or 316L stainless steel plated with Pt. More preferably, the second electrode section is made of nickel foam (Ni) or nickel mesh plated with Pd. Nickel foam (Ni) and nickel mesh have high HER activity and low cost, and their porous structure promotes bubble release; the surface Pd plating can further improve HER efficiency. 316L stainless steel plated with Pt has stronger corrosion resistance. The reduction hydrogen evolution reaction occurs at the second electrode section, while maintaining the stability of the Zr4+ electrolytic environment, providing good resistance to reducing environments and avoiding hydrogen embrittlement or corrosion of the material caused by cathode hydrogen evolution.

[0074] Preferably, the conductive connector is a polymer sheet or a metal sheet plated with a conductive material. The polymer sheet plated with a conductive material can be polyimide (PI) plated with Au or silver (Ag), which is lightweight, reducing weight by more than 50% compared to pure metals, and as a flexible polymer, it can adapt to the thermal expansion and contraction of the electrodes; the metal sheet plated with a conductive material can be titanium plated with Pt, pure titanium (Ti) sheet, or pure nickel (Ni) sheet, which can adapt to high current scenarios and has high reliability.

[0075] Preferably, the solution conveying mechanism includes an adjusting conveying pipe, one end of which is connected to the outlet. An electrolyte storage tank is located outside the adjusting conveying pipe. The end of the adjusting conveying pipe furthest from the outlet is connected to the electrolytic cell via a three-way connecting pipe. A three-way control valve is installed at the three-way connection point of the three-way connecting pipe. The three-way control valve controls whether the electrolyte directly enters the electrolytic cell or is temporarily stored in the electrolyte storage tank. This is suitable for small-scale intermittent production, is simple and direct, and has low cost, requiring only pipes, valves, and a storage tank, resulting in low equipment investment. A pneumatic butterfly valve can be selected as the three-way control valve.

[0076] Preferably, the solution conveying mechanism includes an adjusting conveying pipe, one end of which is connected to the outlet, and the end of the adjusting conveying pipe away from the outlet is connected to a zirconium salt solution pretreatment mechanism. An electrolyte storage tank is externally located on the zirconium salt solution pretreatment mechanism. The electrolyte storage tank and the zirconium salt solution pretreatment mechanism are connected to an electrolytic cell via a three-way connecting pipe, and a three-way control valve is provided at the three-way connection point of the three-way connecting pipe. The integrated zirconium salt solution pretreatment mechanism can remove undissolved particles or adjust dispersion, improving the uniformity of the electrolyte. The three-way control valve allows for selection of whether the solution is directly fed into the electrolytic cell or pretreated first, providing flexible switching to adapt to different process requirements.

[0077] Preferably, the solution conveying mechanism includes an adjusting conveying pipe, one end of which is connected to the discharge port. An electrolyte pretreatment mechanism is provided outside the adjusting conveying pipe. The electrolyte pretreatment mechanism and the end of the adjusting conveying pipe away from the discharge port are connected to the electrolytic cell through a three-way connecting pipe. A three-way control valve is provided at the three-way connection of the three-way connecting pipe.

[0078] The input end of the electrolyte pretreatment mechanism is connected to an electrolyte storage tank via an electrolyte delivery pipe. The electrolyte storage tank temporarily stores the raw electrolyte, while the electrolyte pretreatment mechanism independently performs pH adjustment or temperature control, and then delivers the electrolyte to the electrolytic cell via a three-way control valve. This provides high process controllability, as electrolyte pretreatment and electrolysis are separated. The independent electrolyte pretreatment mechanism facilitates individual optimization of parameters at each stage, such as a pretreatment pH of 8–10 and a specific electrolysis pH of 7–8.

[0079] Preferably, the solution conveying mechanism includes an adjusting conveying pipe, one end of which is connected to the discharge port, and the end of the adjusting conveying pipe away from the discharge port is connected to a zirconium salt solution pretreatment mechanism. An electrolyte pretreatment mechanism is provided outside the zirconium salt solution pretreatment mechanism. The electrolyte pretreatment mechanism and the zirconium salt solution pretreatment mechanism are connected to the electrolytic cell together through a three-way connecting pipe, and a three-way control valve is provided at the three-way connection of the three-way connecting pipe.

[0080] The input end of the electrolyte pretreatment mechanism is connected to an electrolyte storage tank via an electrolyte delivery pipe. The combined pretreatment of zirconium salt solution and electrolyte provides dual protection. The zirconium salt solution pretreatment mechanism addresses dispersion issues (e.g., ultrasonically breaking down agglomerates), while the electrolyte pretreatment mechanism regulates physicochemical properties such as conductivity and temperature. A three-way control valve provides an emergency bypass, allowing production to continue even if one pretreatment process fails. This system is suitable for large-scale production of high-purity nano-ZrO2.

[0081] Preferably, a pH sensor is installed in the adjustment and delivery pipeline. Online pH detection ensures stable electrolyte pH, with a target pH of 8-10, preventing uneven ZrO2 precipitation caused by localized over-acidity / alkalinity. The pH sensor data can be linked to a three-way control valve or pretreatment mechanism to automatically replenish the acid-base regulator.

[0082] Preferably, the zirconium salt solution pretreatment mechanism includes a pretreatment chamber with two sets of partitions arranged side-by-side inside. These partitions sequentially divide the pretreatment chamber into a raw material chamber, a first mixing chamber, and a second mixing chamber. A mixing and stirring rod is rotatably mounted in both the raw material chamber and the first mixing chamber within the pretreatment chamber. A stepped mixing method is employed: the raw material chamber is used for initial dispersion of zirconium salt agglomerates; additives, such as complexing agents, are added in the first mixing chamber for homogenization; and the pH or temperature is finely adjusted in the second mixing chamber to ensure solution stability. The partitions physically isolate the reactions at each stage, preventing backmixing and contamination of the finished product by untreated solution. A three-stage chamber structure is adopted: high-speed shearing in the raw material chamber → gentle stirring in the first mixing chamber → static mixing in the second mixing chamber.

[0083] Preferably, the upper end of the partition plate has a solution outlet located above the mixing and stirring rod. A filter screen is installed at the solution outlet, and the filter screen is partially surrounded by an inverted U-shaped solution baffle. Preferably, the filter screen has a pore size of 1μm to 10μm; preferably 2μm to 9μm; preferably 3μm to 8μm; preferably 4μm to 7μm; preferably 5μm to 6μm. The filter screen effectively intercepts undissolved particles; the inverted U-shaped solution baffle guides the solution to overflow from above the filter screen, preventing direct impact and deformation of the screen; the semi-enclosed structure reduces splashing and keeps the chamber clean. The filter screen is made of 316L stainless steel sintered mesh, which has good corrosion resistance; the opening height of the inverted U-shaped baffle needs to be 10 to 15mm above the liquid surface to prevent siphoning.

[0084] Preferably, a protective cover is provided above the pretreatment chamber, and a guide groove is formed on the protective cover. The inverted U-shaped solution blocking cover is slidably disposed within the guide groove. The protective cover is made of PP plastic, which has good corrosion resistance; the protective cover is transparent for easy observation.

[0085] Preferably, the protective cover of the mechanism is equipped with a push-out cylinder, and the inverted U-shaped solution blocking cover is connected to the push-out end of the push-out cylinder. The push-out cylinder can realize the automatic lifting and lowering of the inverted U-shaped solution blocking cover, which facilitates filter replacement or cleaning without stopping the machine for disassembly. The pushing speed of the push-out cylinder can be adjusted from 5cm / s to 10cm / s, which can avoid solution disturbance; the automated design can improve maintenance efficiency.

[0086] Preferably, the electrolyte pretreatment mechanism is a simplified version of the zirconium salt solution pretreatment mechanism, which includes only a pretreatment chamber, a mixing and stirring rod rotatably disposed in the pretreatment chamber, and a conductivity meter disposed in the pretreatment chamber.

[0087] Preferably, the zirconium salt solution pretreatment mechanism includes an axial lifting mechanism located outside the pretreatment chamber, with a protective cover installed at the lifting end of the axial lifting mechanism. The axial lifting mechanism is a structure consisting of a servo motor and a ball screw, with the protective cover threadedly connected to the ball screw. The height of the protective cover can be flexibly adjusted.

[0088] Preferably, the mixing rod includes a mixing rod body, which is rotatably disposed in the pretreatment chamber; the pretreatment chamber is provided with a drive motor, the drive end of which is connected to one end of the mixing rod body, and the mixing rod body is provided with a plurality of mixing blades distributed along the length of the mixing rod body;

[0089] The stirring blade includes a stirring blade body, which is mounted on the stirring rod body. A set of stirring vanes are arranged opposite each other on the stirring blade body, and a guide plate protrudes from the surface of each stirring vane. A drive motor is directly connected to the stirring rod body, providing stable torque. The integrated design reduces transmission components and lowers the failure rate. The drive motor is a variable frequency motor, preferably rotating at 450 rpm to 550 rpm in the raw material chamber, and preferably at 500 rpm. Preferably, the rotation speed in the first mixing chamber is 150 rpm to 250 rpm, and preferably at 200 rpm. The stirring blade body provides basic shearing action, breaking up zirconium salt agglomerates; the stirring vanes form a bidirectional vortex, improving the radial mixing efficiency of the solution and shortening the mixing time by 30%; the guide plate enhances local mass transfer.

[0090] Preferably, the guide plate has grooves on both opposite sides. The groove design generates micro-turbulence and enhances local mass transfer. The groove depth is preferably 3mm to 5mm, and more preferably 4mm.

[0091] Preferably, a rear sleeve is fitted onto the end of the stirring rod body away from the drive motor, and multiple tail stirring blades are arranged circumferentially on the outer periphery of the rear sleeve. The tail stirring blades at the rear sleeve provide enhanced stirring at the end; the rear sleeve also offsets the load at the front end of the stirring rod, reducing bearing wear.

[0092] Preferably, a front sleeve is provided on the stirring rod body near the drive motor, and multiple front stirring blades are arranged circumferentially on the outer periphery of the front sleeve, with the front stirring blades located within the raw material chamber. The front stirring blades at the front sleeve, situated within the high-solids-content raw material chamber, employ a 45° large inclination angle design to enhance shear force; the front sleeve also protects the drive end bearing from particle impact. The guide plate groove and the bidirectional stirring blades form a three-dimensional flow field, resulting in better stirring and mixing effects.

[0093] The present invention has the following beneficial effects: (1) Adjusting the pH value of the zirconium salt solution to an alkaline environment of 8-10 can effectively promote the hydrolysis of zirconium salt into Zr(OH)4 colloid and avoid the introduction of impurities under acidic conditions; the ultrasonic-assisted electrolysis method can break up agglomerates through ultrasonic cavitation, promote the uniform dispersion of zirconium precursors, and form nanoparticles with small particle size and narrow distribution; the segmented heating electrolysis method can control the hydrolysis-condensation rate through temperature gradient, avoid explosive nucleation, improve crystallinity and dispersibility, and finally obtain highly dispersed nanoparticles; (2) Nano-zirconia is synthesized by one-step electrolysis. During the electrolysis process, hydrogen is generated at the cathode, 2H2O+2e - →H₂↑+2OH⁻, zirconium oxide salt is produced at the anode, Zr 4+ →ZrO2 can achieve the co-production of hydrogen energy and high-value-added nano-zirconium dioxide materials. Compared with the traditional sol-gel method, it can reduce washing and purification steps and reduce wastewater discharge; (3) The nano-zirconium dioxide produced is simple to produce. It couples electrolytic hydrogen production with nano-zirconium dioxide synthesis, which is green; (4) The solvent mixing cylinder and electrolysis chamber are integrated on the frame to reduce the equipment footprint and facilitate assembly line operation. The rigid frame can also reduce vibration interference and ensure the stability of the electrolysis process. The frame can be made of stainless steel 304 material; The zirconium salt solution is directly ultrasonically treated in the solvent mixing cylinder to avoid secondary pollution or agglomeration caused by transfer. Ultrasonic cavitation can also promote the uniform mixing of zirconium salt with complexing agents, dispersants and other additives. Combined, improve the uniformity of precursor solution; (5) The solution delivery mechanism accurately introduces the mixed solution into the electrolytic cell through pump or gravity flow, which is controllable and avoids manual operation error. The adjustment delivery pipeline of the solution delivery mechanism is equipped with a corrosion-resistant peristaltic pump. The adjustment delivery pipeline adopts PTFE pipeline, which can effectively prevent metal ion contamination of the delivery solution; The solution delivery process adopts a relatively closed system, which can reduce air contact and prevent Zr4+ hydrolysis or impurity introduction; The bipolar electrode structure is set up, which can reduce the energy consumption ratio by about 15% compared with the traditional single-polar electrolysis. The first electrode section corresponds to the anode chamber inserted into the electrolytic cell, oxidizing Zr4+ to ZrO2, and at the same time, oxygen is generated, 4OH-→O2↑+2H2O+4e - The second electrode section corresponds to the cathode chamber of the electrolytic cell, where H2O is reduced to produce hydrogen: 2H2O + 2e- -→H2↑+2OH-, the whole can realize hydrogen-zirconium co-production; the conductive connector can ensure the stability of the potential difference between the two electrode sections and avoid uneven current distribution; the anode chamber and cathode chamber in the electrolytic cell are designed in a partitioned manner to prevent H2 from entering the anode area and affecting the purity of ZrO2, and avoid cross-contamination of products; (6) the whole adopts the process of ultrasonic solvent mixing → bipolar electrode electrolysis → product collection, which is fully closed and controllable and suitable for continuous production; among them, the by-product OH- of water electrolysis to produce hydrogen can be recycled to adjust the pH, which can be utilized as a resource; a pH sensor and a viscometer are installed in the solvent mixing cylinder, and a pH sensor, a temperature sensor and a current sensor are installed in the electrolysis chamber. Attached Figure Description

[0094] Figure 1 These are SEM images of the particle size of nano-zirconium dioxide in Examples 1-6 of this invention; Figure 2 This is a first three-dimensional structural diagram of the device of the present invention; Figure 3 This is a schematic diagram of the structure of the stirring component of the present invention; Figure 4 This is a schematic diagram of the structure of the inner spiral guide plate and the outer spiral guide plate of the present invention;

[0095] Figure 5 This is a schematic diagram of the structure of the reactant addition cylinder of the present invention; Figure 6 yes Figure 7 BB section diagram; Figure 7 This is a schematic diagram of the structure at the partition plate of the present invention; Figure 8 This is a schematic diagram of the structure of the zirconium salt solution pretreatment mechanism of the present invention; Figure 9 This is a schematic diagram of the electrolyte pretreatment mechanism of the present invention; Figure 10 This is a schematic diagram of the structure of the electrolyte storage tank of the present invention; Figure 11 This is a schematic diagram of the structure of the pretreatment chamber of the present invention; Figure 12 This is a schematic diagram of the structure of the electrolytic cell in this invention; Figure 13 This is a schematic diagram of the structure of the electrode body of the present invention; Figure 14 This is a schematic diagram of the structure at the first groove surface of the present invention; Figure 15 This is a schematic diagram of the structure of the stirring rod body of the present invention; Figure 16 This is a schematic diagram of the structure of the main body of the stirring blade of the present invention; Figure 17 yes Figure 15 Enlarged view of point A in the image.

[0096] The labels in the attached diagram are as follows: 100-Frame; 200-Electrolysis chamber; 204-Electrolytic cell; 205-Transparent window; 206-Bipolar electrode; 300-Solvent mixing cylinder; 301-Inlet; 302-Outlet; 303-Reactant storage chamber; 304-Transparent observation window; 500-Stirring component; 501-Stirring shaft; 502-First electric telescopic rod; 503-Second electric telescopic rod; 504-Inner spiral guide plate; 505-Outer spiral guide plate; 600-Stirring motor; 700-Solution conveying mechanism; 701- Adjusting the conveying pipeline; 702-Zirconium salt solution pretreatment mechanism; 7022-Pretreatment chamber; 70221-Raw material chamber; 70222-First mixing chamber; 70223-Second mixing chamber; 7023-Mechanism protective cover; 7024-Baffle plate; 7025-Inverted U-shaped solution baffle; 7026-Guide groove; 7027-Ejection cylinder; 7028-Mixing stirring rod; 70281-Stirring rod body; 70283-Drive motor; 70284-Stirring blade; 70284a-Stirring blade body; 70284b- Stirring blade; 70284c-Guide plate; 7029-Solution outlet; 7020-Filter screen; 703-Electrolyte pretreatment mechanism; 704-T-connection pipe; 705-Electrolyte delivery pipe; 706-Electrolyte storage tank; 707-T-control valve; 708-Rear sleeve; 709-Front sleeve; 710a-Tail stirring blade; 710b-Front stirring blade; 711-Axial lifting mechanism; 800-Reactant addition cylinder; 8011-Steel ball roller; 8012-Arc groove; 802-Separating component; 8021-Flexible separator Layer; 8022-Umbrella-shaped support frame; 8023-Support spindle; 8024-Inclined support rod; 8025-Separating layer plate; 8026-Separating surface pusher; 8027-Shaft seat; 8028-Support arm; 8029-First ear plate; 8020-Second ear plate; 803a-Upper inner cavity; 803b-Lower inner cavity; 900-Electrode body; 901-First electrode segment; 902-Second electrode segment; 903-Conductive connector; 904-Insulating layer; 905-Conical guide surface; 906-First groove surface; 907-Second groove surface. Detailed Implementation

[0097] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0098] A method for preparing highly dispersed nano-zirconia for hydrogen production via water electrolysis includes the following steps:

[0099] (S01) Take an appropriate amount of zirconium salt solution and adjust the pH value of the zirconium salt solution to 8-10; the zirconium salt solution in step (S01) is prepared by mixing zirconium salt with a deionized aqueous solvent; the zirconium salt in step (S01) is selected from one or more of zirconium sulfate or zirconium nitrate; the mass concentration of the zirconium salt solution in step (S01) is 45%-70%; the mass concentration of the zirconium salt solution in step (S01) is 50%-65%; the mass concentration of the zirconium salt solution in step (S01) is 55%-60%; the pH value of the zirconium salt solution in step (S01) is adjusted by a surface additive; the surface additive is an amine-containing organic compound; the amine-containing organic compound is selected from one or more of ethylenediamine, triethylamine, and tetramethylethylenediamine; a dispersant and a stabilizer are added to the zirconium salt solution in step (S01); the dispersant is selected from polyethylene glycol and polyethylene. One or more of alcohol, polymethyl methacrylate, or sodium polystyrene sulfonate; the stabilizer is a combination of sodium dodecyl sulfate and polyelectrolyte; the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 3-10:8-25:1; the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 4-9:10-20:1; the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 5-8:12-18:1; the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 6-7:14-16:1; the zirconium salt solution to be introduced into the electrolytic cell in step (S01) is centrifuged to obtain the supernatant, and the supernatant is introduced into the electrolytic cell in step (S02); the centrifugation speed is 3000 rpm-5000 rpm; the centrifugation speed is 3500 rpm-4500 rpm; the centrifugation speed is 4000 rpm;

[0100] (S02) The zirconium salt solution after pH adjustment in step (S01) is introduced into an electrolytic cell for ultrasonication; the ultrasonic frequency in step (S02) is 20kHz to 40kHz; the ultrasonic frequency in step (S02) is 25kHz to 35kHz; the ultrasonic frequency in step (S02) is 30kHz; the ultrasonic time in step (S02) is 25min to 45min; the ultrasonic time in step (S02) is 30min to 40min; the ultrasonic time in step (S02) is 35min; the electrolyte in the electrolyte solution in step (S02) is either sodium sulfate or potassium nitrate, or a mixture of both; the molar ratio of zirconium ions to electrolyte in step (S02) is 1:0.1 to 0.3; the molar ratio of zirconium ions to electrolyte in step (S02) is 1:0.2;

[0101] The zirconium salt solution after ultrasonic treatment in step (S02) undergoes pretreatment, including the following steps:

[0102] (S02-A1) After adding an appropriate amount of complexing agent to the zirconium salt solution, mix thoroughly with a stirrer; the complexing agent in step (S02-A1) is selected from one or more of ethylenediaminetetraacetic acid, aminotriacetic acid, or diethylenetriaminepentaacetic acid; the amount of complexing agent added is 0.1% to 1% (w / v) of the total volume of the zirconium salt solution; the amount of complexing agent added is 0.2% to 0.9% (w / v) of the total volume of the zirconium salt solution; the amount of complexing agent added is 0.3% to 0.8% (w / v) of the total volume of the zirconium salt solution; the amount of complexing agent added is 0.4% to 0.7% (w / v) of the total volume of the zirconium salt solution; the amount of complexing agent added is 0.5% to 0.6% (w / v) of the total volume of the zirconium salt solution;

[0103] (S02-A2) The zirconium salt solution after mixing in step (S02-A1) is passed through a filter membrane to remove insoluble matter and impurities;

[0104] The preparation of the electrolyte in the electrolytic cell in step (S02) includes the following steps:

[0105] (S02-B1) An initial electrolyte containing deionized water and a buffer is prepared in an electrolytic cell; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 45%–70%; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 50%–65%; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 55%–60%; the buffer in step (S02-B1) is sodium dihydrogen phosphate;

[0106] (S02-B2) Add an appropriate amount of electrolyte to the initial electrolyte solution in step (S02-B1);

[0107] (S02-B3) Add a conductivity enhancer equivalent to 20% to 50% of the amount of buffer added to the electrolyte in step (S02-B2); the conductivity enhancer in step (S02-B3) is selected from one or more of potassium nitrate or potassium sulfate;

[0108] (S02-B4) Add a surfactant equivalent to 1% to 3% of the amount of buffer added to the electrolyte in step (S02-B3), and mix thoroughly using a stirrer; the surfactant in step (S02-B4) is selected from one or more of sodium dodecyl sulfate, polysorbate, or octylbenzeneol.

[0109] (S03) The zirconium salt solution from step (S02) is subjected to segmented heating electrolysis via bipolar electrodes in an electrolytic cell; the electrolysis conditions in step (S03) are preset as follows: initial voltage 3-5 volts, current density 20 mA / cm². 2 ~50mA / cm 2The electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 3.5–4.5 volts, current density 30 mA / cm². 2 ~40mA / cm 2 The electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 4 volts, current density 35 mA / cm². 2 The segmented heating electrolysis temperature range in step (S03) is 25℃~45℃.

[0110] The segmented heating in step (S03) is as follows: (S03-1) Before starting electrolysis, the temperature of the electrolyte in the electrolytic cell is adjusted to 25°C.

[0111] (S03-2) Gradually raise the electrolyte temperature from step (S03-1) to 35°C at a rate of 0.5°C to 2.5°C per minute; (S03-3) When the electrolyte reaches the first stage temperature of 35°C, maintain the first stage temperature and continue electrolysis for 10 to 15 minutes; (S03-4) After the electrolysis in step (S03-3) is completed, continue to raise the electrolyte temperature to the final working temperature of 45°C at a rate of 0.5°C to 2.5°C per minute; (S03-5) Continue to maintain the electrolysis process of the electrolyte that has reached the final working temperature in step (S03-4) for 30 to 80 minutes;

[0112] (S04) After the electrolysis in step (S03) is completed, the product in the electrolytic cell is dried and calcined to obtain nano-zirconia; the drying in step (S04) is vacuum drying or freeze drying; the vacuum drying temperature is 50℃~70℃; the vacuum drying temperature is 55℃~65℃; the vacuum drying temperature is 60℃; the vacuum drying time is 8h~16h; the vacuum drying time is 10h~14h; the vacuum drying time is 11h~13h; the vacuum drying time is 12h; the freeze drying temperature is -60℃~-40℃; the freeze drying temperature is -55℃~-45℃; the freeze drying temperature is -50℃; the freeze drying time is 12h~36h; the freeze drying time is 16h~32h; the freeze drying time is 20h~28h; the freeze drying time is 2 4h; the calcination temperature in step (S04) is 300℃~700℃; the calcination temperature in step (S04) is 350℃~650℃; the calcination temperature in step (S04) is 400℃~600℃; the calcination temperature in step (S04) is 450℃~550℃; the calcination temperature in step (S04) is 500℃; the calcination time in step (S04) is 2h~4h; the calcination time in step (S04) is 2.5h~3.5h; the calcination time in step (S04) is 3h; the average particle size of nano-zirconia in step (S04) is 10~50 nm; the dielectric constant of nano-zirconia in step (S04) at 20kHz is 38~42, and the electrical loss tangent is 0.0015~0.0025. In step (S04), the dielectric constant of nano-zirconia at 25 kHz is 39–43, and the electrical loss tangent is 0.0014–0.0019. In step (S04), the dielectric constant of nano-zirconia at 30 kHz is 40–44, and the electrical loss tangent is 0.0013–0.0017. In step (S04), the product collected in the electrolytic cell is washed through a ceramic membrane.

[0113] Example 1: A method for preparing highly dispersed nano-zirconia for hydrogen production via water electrolysis, comprising the following steps:

[0114] (S01) Take an appropriate amount of zirconium salt solution and adjust the pH value of the zirconium salt solution to 8.9-9.5; the zirconium salt solution in step (S01) is prepared by adding zirconium salt to a deionized aqueous solvent and mixing; the zirconium salt in step (S01) is selected from zirconium sulfate; the mass concentration of the zirconium salt solution in step (S01) is 45%; the pH value of the zirconium salt solution in step (S01) is adjusted by a surface additive; the surface additive is an amine-containing organic compound; the amine-containing organic compound is selected from ethylenediamine; a dispersant is added to the zirconium salt solution in step (S01). The dispersant is selected from polyethylene glycol; the stabilizer is a combination of sodium dodecyl sulfate and polyelectrolyte; the molar ratio of dispersant, stabilizer and zirconium salt in zirconium salt solution is 3:8:1; the zirconium salt solution to be introduced into the electrolytic cell in step (S01) is centrifuged to obtain the supernatant, and the supernatant is introduced into the electrolytic cell in step (S02); the centrifugation speed is 3000 rpm; the turbidity of the supernatant after centrifugation is NTU<5; dynamic light scattering DLS shows that the initial zirconium salt agglomerate particle size D50≈200nm, which is reduced to D50≈80nm after centrifugation;

[0115] (S02) The zirconium salt solution after pH adjustment in step (S01) is introduced into an electrolytic cell for ultrasonication; the ultrasonic frequency in step (S02) is 20kHz; the ultrasonic time in step (S02) is 45min; sodium sulfate is used as the electrolyte in the electrolyte in step (S02); the molar ratio of zirconium ions to electrolyte in the electrolytic cell in step (S02) is 1:0.1; after ultrasonication n, the solution D50 is further reduced to ≈50nm; the ultrasonic energy consumption is approximately 0.5kWh / L;

[0116] The zirconium salt solution after ultrasonic treatment in step (S02) is pretreated by the following steps: (S02-A1) After adding an appropriate amount of complexing agent to the zirconium salt solution, it is thoroughly mixed using a stirrer; the complexing agent in step (S02-A1) is selected from ethylenediaminetetraacetic acid; the amount of complexing agent added is 0.1% of the total volume of the zirconium salt solution; (S02-A2) The zirconium salt solution after mixing in step (S02-A1) is filtered through a filter membrane to remove insoluble matter and impurities;

[0117] The preparation of the electrolyte in the electrolytic cell in step (S02) includes the following steps: (S02-B1) preparing an initial electrolyte containing deionized water and a buffer in the electrolytic cell; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 45%; the buffer in step (S02-B1) is sodium dihydrogen phosphate; (S02-B2) adding an appropriate amount of electrolyte to the initial electrolyte in step (S02-B1); (S02-B3) adding a conductivity enhancer equivalent to 20% of the amount of buffer added to the electrolyte in step (S02-B2); the conductivity enhancer in step (S02-B3) is selected from potassium nitrate; (S02-B4) adding a surfactant equivalent to 1% of the amount of buffer added to the electrolyte in step (S02-B3) and mixing thoroughly with a stirrer; the surfactant in step (S02-B4) is selected from sodium dodecyl sulfate.

[0118] (S03) The zirconium salt solution from step (S02) is subjected to segmented heating electrolysis via bipolar electrodes in an electrolytic cell; the electrolysis conditions in step (S03) are preset as follows: initial voltage 3 volts, current density 20 mA / cm². 2 The segmented heating electrolysis temperature range in step (S03) is 25℃~45℃; the electrolyte containing 0.1mol / L Na2SO4 + 20% KNO3 has a conductivity of ≈45mS / cm; the Zr4+→ZrO2 conversion rate is ≈85%, and the cathode hydrogen evolution rate is ≈0.12L / h·cm. 2 ,

[0119] The segmented heating in step (S03) is as follows: (S03-1) Before starting electrolysis, the temperature of the electrolyte in the electrolytic cell is adjusted to 25°C.

[0120] (S03-2) Gradually increase the electrolyte temperature from step (S03-1) to 35°C at a rate of 0.5°C per minute; (S03-3) When the electrolyte reaches the first-stage temperature of 35°C, maintain the first-stage temperature and continue electrolysis for 15 minutes; nucleation becomes dominant, the number of particles increases, and the TEM count ≈ 10. 4 Particles / μm 2 (S03-4) After the electrolysis in step (S03-3) is completed, continue to raise the electrolyte temperature to the final working temperature of 45°C at a rate of 0.5°C per minute; (S03-5) Continue to maintain the electrolyte at the final working temperature in step (S03-4) for 80 minutes; crystal growth, the proportion of tetragonal ZrO2 increases to ≈70%;

[0121] (S04) After electrolysis in step (S03), the product in the electrolytic cell is collected, dried, and calcined to obtain nano-zirconia; the drying in step (S04) is vacuum drying; the vacuum drying temperature is 50℃; the vacuum drying time is 16h; the calcination temperature in step (S04) is 300℃; the calcination time in step (S04) is 4h; the average particle size of the nano-zirconia in step (S04) is 10-50 nanometers, such as... Figure 1 As shown in (a); in step (S04), the dielectric constant of nano-zirconia at 20 kHz is 38–42, exhibiting excellent dielectric properties, with a loss tangent of 0.0015–0.0025; in step (S04), the product collected in the electrolytic cell is washed through a ceramic membrane; TEM statistics show that the average particle size after calcination is D50≈35 nm, with a distribution range of 10–50 nm, meeting the requirements for high dispersibility; the BET specific surface area is ≈120 m². 2 / g. The process parameters of Example 1 can stably prepare highly dispersed nano-ZrO2 with excellent dielectric properties.

[0122] Example 2: Preparation method of highly dispersible nano-zirconia for hydrogen production by electrolysis of water. This example is largely the same as Example 1, except that the zirconium salt in step (S01) is selected from zirconium nitrate; the mass concentration of the zirconium salt solution in step (S01) is 70%; the amine-containing organic compound is selected from triethylamine, and the pH is stabilized at 9.8±0.2; the dispersant is selected from polyvinyl alcohol; the molar ratio of dispersant, stabilizer and zirconium salt in the zirconium salt solution is 10:25:1; the centrifugation speed is 5000 rpm, and the D50 of the supernatant after centrifugation is approximately 60 nm; the ultrasonic frequency in step (S02) is 40 kHz; the ultrasonic time in step (S02) is 25 min, and after ultrasonication, the solution D50 is approximately 30 nm, which more efficiently breaks up agglomerates, and the ultrasonic energy consumption is 0.3 kWh / L; the electrolyte in the electrolyte in the electrolytic cell in step (S02) is potassium nitrate; the electrolytic cell in step (S02) The molar ratio of zirconium ions to electrolyte is 1:0.3; the complexing agent in step (S02-A1) is selected from aminotriacetic acid; the amount of complexing agent added is 1% (w / v) of the total volume of the zirconium salt solution; the mass concentration of buffer in the initial electrolyte in step (S02-B1) is 70%; (S02-B3) a conductivity enhancer equivalent to 50% of the buffer added amount is added to the electrolyte in step (S02-B2) to reduce the cell voltage to 4.2V; the conductivity enhancer in step (S02-B3) is selected from potassium sulfate; (S02-B4) a surfactant equivalent to 3% of the buffer added amount is added to the electrolyte in step (S02-B3) and thoroughly mixed with a stirrer; the surfactant in step (S02-B4) is selected from polysorbate; the electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 5 volts, current density 50 mA / cm². 2Electrolyte conductivity ≈ 65 mS / cm, Zr⁴⁺ → ZrO₂ conversion ≈ 92%, cathode hydrogen evolution rate ≈ 0.28 L / h·cm 2 (S03-2) Gradually increase the electrolyte temperature from step (S03-1) to 35°C at a rate of 2.5°C per minute; (S03-3) When the electrolyte reaches the first-stage temperature of 35°C, maintain the first-stage temperature and continue electrolysis for 10 minutes; (S03-4) After the electrolysis in step (S03-3) is completed, continue to increase the electrolyte temperature to the final operating temperature of 45°C at a rate of 2.5°C per minute; (S03-5) Reach the final operating temperature from step (S03-4). The electrolyte was used to continue the electrolysis process for 30 minutes; the vacuum drying temperature was 70℃; the vacuum drying time was 8 hours; the calcination temperature in step (S04) was 700℃; the calcination time in step (S04) was 2 hours; the dielectric constant of the nano-zirconia in step (S04) at 40kHz was 42-45, exhibiting excellent high-frequency performance, high reaction efficiency, and an electrical loss tangent of 0.0011-0.0016. The average particle size after calcination was D50≈25nm, ranging from 10 to 40nm. Figure 1 As shown in (b), the dispersion is good, and TEM shows that the particles are spherical with no obvious agglomeration. The tetragonal ZrO2 accounts for approximately 95%. Through high-concentration zirconium salt, high-frequency ultrasound, rapid heating electrolysis, and high-temperature calcination, finer and more crystalline nano-ZrO2 was obtained, and the dielectric properties were significantly improved.

[0123] Example 3: Preparation method of highly dispersible nano-zirconia for hydrogen production by electrolysis of water. This example is largely the same as Example 1, except that the zirconium salt in step (S01) is a mixture of zirconium sulfate and zirconium nitrate in a mass ratio of 1:1; the mass concentration of the zirconium salt solution in step (S01) is 55%; the solution viscosity is approximately 80 cP; the amine-containing organic compound is selected from tetramethylethylenediamine to stabilize the pH at 9.5 ± 0.1; the dispersant is selected from polymethyl methacrylate; and the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 4:10. 1. The combination of polymethyl methacrylate (PMMA) and SDS resulted in a particle zeta potential of approximately -35 mV, indicating superior electrostatic stability. The centrifugation speed was 4000 rpm, and the supernatant D50 after centrifugation was approximately 70 nm. The ultrasonic frequency in step (S02) was 30 kHz. The ultrasonic time in step (S02) was 35 min, resulting in a solution D50 of approximately 40 nm and ultrasonic energy consumption of approximately 0.4 kWh / L, demonstrating excellent energy efficiency. The electrolyte in the electrolytic cell of step (S02) was a mixture of sodium sulfate and potassium nitrate, with a low molar ratio. The molar ratio is 3:1, which avoids excessive KNO3 leading to ammonia evolution at the cathode. The conductivity is approximately 55 mS / cm, combining the stability of Na2SO4 with the high conductivity of KNO3. In step (S02), the molar ratio of zirconium ions to electrolyte in the electrolytic cell is 1:0.2. The complexing agent in step (S02-A1) is selected from diethylenetriaminepentaacetic acid. The amount of complexing agent added is 0.6% (w / v) of the total volume of the zirconium salt solution. In step (S02-B1), the mass concentration of the buffer in the initial electrolyte is 55%. (S02-B3) In step... In step (S02-B2), a conductivity enhancer equivalent to 35% of the buffer addition amount is added to the electrolyte; in step (S02-B3), the conductivity enhancer is selected from a mixture of potassium nitrate and potassium sulfate; in step (S02-B4), a surfactant equivalent to 2% of the buffer addition amount is added to the electrolyte in step (S02-B3), and the mixture is thoroughly mixed using a stirrer; the surfactant in step (S02-B4) is selected from octylbenzeneol; the electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 4 volts, current density 35 mA / cm². 2 (S03-2) Gradually increase the electrolyte temperature from step (S03-1) to 35℃ at a rate of 1℃ per minute; (S03-3) When the electrolyte reaches the first-stage temperature of 35℃, maintain the first-stage temperature and continue electrolysis for 12 minutes; (S03-4) After the electrolysis in step (S03-3) is completed, continue to increase the electrolyte temperature to the final working temperature of 45℃ at a rate of 1.5℃ per minute; (S03-5) Continue electrolysis for 55 minutes with the electrolyte having reached the final working temperature in step (S03-4); the cell voltage is stable at 4.0V, and the polarization loss is low; the Zr4+→ZrO2 conversion rate is approximately 89%, and the cathode hydrogen evolution rate is approximately 0.20L / h·cm. 2The vacuum drying temperature was 60℃; the vacuum drying time was 12h; the calcination temperature in step (S04) was 500℃; the calcination time in step (S04) was 3h; the dielectric constant of the nano-zirconia at 30kHz in step (S04) was 40-44, the electrical loss tangent was 0.0013-0.0017, the average particle size D50 after calcination was 30nm, and the particle size distribution range was 15-45nm. Figure 1 As shown in (c), it has excellent sphericity and the proportion of tetragonal ZrO2 is approximately 85%.

[0124] By mixing zirconium salts, using medium-frequency ultrasound, gradient heating electrolysis, and medium-temperature calcination, a good balance is achieved between particle size control, dielectric properties, and process economy. This method is suitable for medium-scale production of high-performance nano-ZrO2, and is especially applicable to applications in dielectric ceramics and catalyst supports.

[0125] Example 4: Preparation method of highly dispersible nano-zirconia for hydrogen production by water electrolysis. This example is largely the same as Example 1, except that the mass concentration of the zirconium salt solution in step (S01) is 50%; the dispersant is selected from sodium polystyrene sulfonate; the molar ratio of dispersant, stabilizer and zirconium salt in the zirconium salt solution is 5:12:1; the combination of sodium polystyrene sulfonate PSS and SDS / polyelectrolyte achieves a zeta potential of -40mV and good electrostatic stability; the centrifugation speed is 3500rpm, and the turbidity of the supernatant after centrifugation is <3NTU, D50≈75nm; the ultrasonic frequency in step (S02) is 25kHz; the ultrasonic time in step (S02) is 30min, and the solution after ultrasonication has D50≈45nm and a specific surface area≈150m². 2 / g, ultrasonic energy consumption ≈0.35kWh / L; the complexing agent in step (S02-A1) is selected from a combination of ethylenediaminetetraacetic acid (EDTA) and aminotriacetic acid (NTA); the amount of complexing agent added is 0.4% (w / v) of the total volume of the zirconium salt solution. EDTA and NTA synergistically chelate Zr4+, resulting in residual free Zr4+ <0.1ppm, which can reduce electrolytic side reactions; the mass concentration of buffer in the initial electrolyte in step (S02-B1) is 50%, and the buffer makes the solution... The electrolyte pH stability is ±0.2; (S02-B3) A conductivity enhancer equivalent to 30% of the buffer addition amount is added to the electrolyte in step (S02-B2); the surfactant in step (S02-B4) is selected from a mixture of sodium dodecyl sulfate and polysorbate, which reduces the surface tension to 28 mN / m, increases the bubble release rate by 20%, and synergistically prevents particle agglomeration; the electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 3.5 volts, current density 30 mA / cm². 2The drying in step (S04) is freeze-drying; the freeze-drying temperature is -60℃; the freeze-drying time is 12h; the product porosity is ≈85%, the specific surface area retention rate is >95%, and the specific surface area is 145±5m². 2 / g; the calcination temperature in step (S04) is 450℃; the calcination time in step (S04) is 3h; the dielectric constant of nano-zirconia in step (S04) at 25kHz is 39~43, the electrical loss tangent is 0.0014~0.0019, and it has good high-frequency adaptability; the Zr4+→ZrO2 conversion rate is ≈88%, the hydrogen evolution efficiency is ≈92%, the proportion of tetragonal ZrO2 is ≈88%, the grain size is ≈32nm, there is no carbon residue, and the average particle size is 35±8nm. Figure 1 As shown in (d), it exhibits good uniformity. Highly uniform nano-ZrO2 was obtained through a complexing agent, mixed surfactants, and freeze-drying, exhibiting excellent dielectric properties and a specific surface area (145 m²). 2 / g) exhibits excellent overall performance and is suitable for electronic device applications requiring high porosity and low dielectric loss, such as 5G filters.

[0126] Example 5: Preparation method of highly dispersible nano-zirconia for hydrogen production by water electrolysis. This example is largely the same as Example 2, except that in step (S01), the mass concentration of the zirconium salt solution is 65%, and the viscosity is approximately 150 cP; the amine-containing organic compound is selected from a mixture of ethylenediamine and tetramethylethylenediamine to stabilize the reaction pH at 10.0 ± 0.1, and the synergistic effect of the amine group enhances the Zr4+ complexation ability; the dispersant is selected from a mixture of polyethylene glycol and polyvinyl alcohol; the molar ratio of dispersant, stabilizer and zirconium salt in the zirconium salt solution is 8:18:1, and the composite dispersant makes the particle zeta potential reach -38 mV; the centrifugation speed is 4500 rpm, and the D50 of the supernatant after centrifugation is approximately 55 nm; the ultrasonic frequency in step (S02) is 35 kHz; the ultrasonic time in step (S02) is 40 min, and the ultrasonication makes the solution D50 approximately 28 nm and the specific surface area approximately 155 m². 2 / g, ultrasonic energy consumption ≈0.45kWh / L; the complexing agent in step (S02-A1) is selected from a mixture of ethylenediaminetetraacetic acid and diethylenetriaminepentaacetic acid; the amount of complexing agent added is 0.7% (w / v) of the total volume of the zirconium salt solution; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 65%; (S02-B3) a conductivity enhancer equivalent to 40% of the amount of buffer added is added to the electrolyte in step (S02-B2); the surfactant in step (S02-B4) is selected from a mixture of sodium dodecyl sulfate and octylbenzeneol; the electrolysis conditions of the electrolytic cell in step (S03) are preset as follows: initial voltage 4.5 volts, current density 40 mA / cm². 2The electrolyte conductivity is approximately 70 mS / cm, the cell voltage is stable at 4.3 V, and the hydrogen evolution rate at the cathode is approximately 0.25 L / h·cm. 2 The anodic ZrO2 deposition rate increased by 20%, the solution surface tension decreased to 25 mN / m, and the bubble detachment diameter decreased to 0.5 mm. The drying in step (S04) was freeze-drying; the freeze-drying temperature was -40℃; the freeze-drying time was 36 h; the product porosity was ≈80%, the pore size distribution was 2–8 nm, and the specific surface area retention rate was >90%. The calcination temperature in step (S04) was 550℃; the calcination time in step (S04) was 3 h; the tetragonal ZrO2 proportion was ≈92%, and the grain size was ≈30 nm. Figure 1 As shown in (e), the amorphous phase is completely eliminated; in step (S04), the dielectric constant of nano-zirconia at 35 kHz is 41–45, and the electrical loss tangent is 0.0012–0.0016. Through the use of composite amine modifiers, mid-to-high frequency ultrasound, and gradient freeze-drying, a good balance is achieved in terms of particle size control, dielectric properties, and porosity of nano-ZrO2. Its mesoporous structure and low dielectric loss characteristics are particularly suitable for high-frequency electronic devices, such as millimeter-wave filters and catalyst supports.

[0127] Example 6: Preparation method of highly dispersible nano-zirconia for hydrogen production by water electrolysis. This example is largely the same as Example 3, except that the mass concentration of the zirconium salt solution in step (S01) is 55%; the amine-containing organic compound is selected from a mixture of triethylamine and tetramethylethylenediamine, which stabilizes the solution pH at 9.7±0.1 and increases the Zr4+ complexation efficiency by 12%; the dispersant is selected from a mixture of polyvinyl alcohol, polymethyl methacrylate, and sodium polystyrene sulfonate, and the three components synergistically inhibit particle agglomeration, resulting in a PDI as low as 0.11; the molar ratio of dispersant, stabilizer, and zirconium salt in the zirconium salt solution is 6:14:1, and the electrostatic-spatial synergistic stabilization mechanism results in a D50 of approximately 65 nm and a Zeta potential of -42 mV for the supernatant after centrifugation, and a D50 of approximately 38 nm and a specific surface area of ​​approximately 148 m² for the solution after sonication. 2 / g, ultrasonic energy consumption 0.38kWh / L; the complexing agent in step (S02-A1) is a mixture of aminotriacetic acid and diethylenetriaminepentaacetic acid, the dual complexing agent reduces electrolytic side reactions by 15%; the amount of complexing agent added is 0.5% (w / v) of the total volume of the zirconium salt solution, and the electrolytic current efficiency reaches 90%; the mass concentration of the buffer in the initial electrolyte in step (S02-B1) is 55%; the surfactant in step (S02-B4) is a mixture of polysorbate and octylbenzyl alcohol, which makes the electrolyte... The surface tension was reduced to 26 mN / m, the bubble detachment time was shortened to 0.3 seconds, the gas-liquid interface behavior was optimized, and the hydrogen evolution efficiency was improved by 8%; the drying in step (S04) was freeze-drying; the freeze-drying temperature was -50℃; the freeze-drying time was 24 h, the product porosity was ≈82%, the mesopore content was >70%, the pore size distribution was 2-6 nm, and the specific surface area retention rate was 93%; the calcination temperature in step (S04) was 450℃, the tetragonal ZrO2 content was ≈86%, and the grain size was ≈35 nm, such as Figure 1 As shown in (f), the carbon residue is <0.5%. Through the use of composite amine modifiers, three-component dispersants, and optimized freeze-drying, nano-ZrO2 exhibits outstanding performance in terms of dielectric consistency and mesoporous structure uniformity. Its low dielectric loss and controllable porosity characteristics make it suitable for high-frequency capacitors and drug carriers.

[0128] like Figure 2 The apparatus for preparing highly dispersible nano-zirconia for hydrogen production by water electrolysis, as shown, includes a frame 100, on which a solvent mixing cylinder 300 and an electrolysis chamber 200 are mounted; the solvent mixing cylinder is connected to the electrolysis chamber via a solution delivery mechanism 700; an ultrasonic generator is installed inside the solvent mixing cylinder; and a device such as... is installed inside the electrolysis chamber. Figure 12 The electrolytic cell 204 shown has a solvent mixing cylinder connected to it via a solution delivery mechanism; a bipolar electrode 206 is provided at the bottom of the electrolytic cell; the bipolar electrode includes, for example,... Figure 13 The electrode body 900 shown has a first electrode segment 901 and a second electrode segment 902 connected to it by a conductive connector 903. The first electrode segment and the second electrode segment are inserted into the anode chamber and cathode chamber of the electrolytic cell respectively.

[0129] The solvent mixing cylinder is equipped with a rotating device such as Figure 3The stirring component 500 shown has a stirring motor 600 located outside the solvent mixing cylinder, with the drive end of the stirring motor connected to the stirring component. The stirring component includes a stirring shaft 501, which is rotatably mounted inside the solvent mixing cylinder. One end of the stirring shaft is connected to the drive end of the stirring motor via a coupling, and the end of the stirring shaft away from the stirring motor is rotatably mounted on the solvent mixing cylinder via a sealed bearing. Multiple sets of first electric telescopic rods 502 and second electric telescopic rods 503 are distributed along the axial direction of the stirring shaft. Each set of first and second electric telescopic rods is arranged in a cross-shaped staggered configuration. The solvent mixing cylinder is equipped with... Figure 4 The inner spiral guide plate 504 and outer spiral guide plate 505 shown form a double spiral structure. The inner spiral guide plate is sequentially connected to the middle of the first and second electric telescopic rods along the axial direction of the stirring shaft. The outer spiral guide plate is sequentially connected to the ends of the first and second electric telescopic rods along the axial direction of the stirring shaft. A transparent observation window 304 for monitoring the zirconium salt solution mixing process is provided on the solvent mixing cylinder. The solvent mixing cylinder is provided with an inlet 301 and an outlet 302, and the outlet is connected to the electrolysis chamber through a solution conveying mechanism.

[0130] The solvent mixing cylinder has multiple reactant storage chambers 303 on its outer wall, each corresponding to a first and second electrically operated telescopic rod in a corresponding group. The reactant storage chambers are threaded together as shown in the image. Figure 5 The reactant adding cylinder 800 shown is divided into an upper inner cavity 803a and a lower inner cavity 803b by an openable and closable partition member 802. The lower inner cavity is connected to the interior of the solvent mixing cylinder. The partition member includes a flexible partition layer 8021, which is elastically disposed on the inner wall surface of the reactant adding cylinder. When the flexible partition layer flexibly contracts, its edge adheres to the inner wall surface of the reactant adding cylinder; when the flexible partition layer flexibly expands, a gap is formed between the edge of the flexible partition layer and the inner wall surface of the reactant adding cylinder. An umbrella-shaped expansion frame 8022 is provided inside the reactant adding cylinder. The opening side of the umbrella-shaped expansion frame adheres to the lower part of the flexible partition layer, and the side of the umbrella-shaped expansion frame away from the flexible partition layer corresponds to the telescopic ends of the first and second electric telescopic rods of the reactant adding cylinder. The umbrella-shaped expansion frame includes a component such as... Figure 6 The shaft seat 8027 shown has a telescopically movable support shaft 8023. One end of the support shaft is attached to the central area of ​​the flexible partition layer, and the other end of the support shaft away from the flexible partition layer extends through the reactant adding cylinder and into the solvent mixing cylinder. The end of the support shaft away from the flexible partition layer corresponds to the telescopic ends of the first and second electric telescopic rods of the reactant adding cylinder. At least three radial connections are provided around the outer periphery of the support shaft. Figure 7The inclined support rod 8024 shown has a ball bearing roller 8011 movably mounted at the end away from the main shaft of the support. The inner wall of the reactant addition cylinder has at least three arc-shaped grooves 8012, and the ball bearing rollers are sealed within the corresponding arc-shaped grooves. The inclined support rod is inclined downwards relative to the horizontal plane at angles of 2 to 10 degrees, 4 to 8 degrees, and 5 to 7 degrees. Separating plates 8025 are hinged to both sides of the inclined support rod, and the separating plates between two inclined support rods are in close contact and sealed, close to the flexible separating layer. Several separating surface pushing members 8026 are rotatably connected to the shaft seat, and these pushing members are rotatably connected to the corresponding separating plates. The partition plate pusher includes several first ear plates 8029 arranged circumferentially along the shaft seat, with support arms 8028 rotatably connected to the first ear plates; a second ear plate 8020 is provided at the bottom of the partition plate, and the second ear plate is rotatably connected to the end of the corresponding support arm away from the shaft seat. The partition plate is a fan-shaped plate, and when the partition plate is not opened, adjacent partition plates and the partition plate and its corresponding support rod are in a sealed fit. The flexible partition layer is made of a chemically resistant flexible material. A transparent window 205 is provided at the top of the electrolytic cell.

[0131] The upper half of the electrode body is covered with something like Figure 14 The insulating layer 904 shown has a portion of the electrode body's outer edge protruding beyond it. This protruding portion of the electrode body is coated with a functional coating. The insulating layer is made of a polymer-based composite material mixed with an inorganic filler. The functional coating is made of a composite material of carbon nanotubes or graphene oxide and platinum or palladium nanoparticles. A TiN transition layer is added between the electrode body and the functional coating. The electrode body has a rectangular structure, with tapered guide surfaces 905 on all four sides of its upper surface. Each tapered guide surface consists of two long-side guide surfaces and two short-side guide surfaces. A first groove surface 906 is formed in the center of the short-side guide surfaces, adopting a trapezoidal structure that is narrower at the top and wider at the bottom. Second groove surfaces 907 are formed at both ends of the long-side guide surfaces, adopting a fan-shaped curved structure that is narrower at the top and wider at the bottom. Both the first and second groove surfaces are coated with a catalyst layer. The catalyst layer is made of carbon nanotubes, graphene oxide, platinum nanomaterials, palladium nanomaterials, or nickel-iron layered bimetallic hydroxide (NiFe-LDH). The first electrode segment is made of a mixture of nickel foam and fluorine-doped tin oxide, or a titanium mesh (Ti plated with platinum (Pt) or iridium-plated (Ir) material; the second electrode segment is made of nickel foam (Ni), nickel mesh, or 316L stainless steel plated with Pt. The conductive connector is a polymer sheet or metal sheet plated with conductive material.

[0132] One real-time method for the solution conveying mechanism includes adjusting the conveying pipe 701, adjusting one end of the conveying pipe to be connected to the outlet, and adjusting the external features of the conveying pipe as shown in the image. Figure 10 The electrolyte storage tank 706 shown is connected to the electrolytic cell via a three-way connecting pipe 704, with the end of the adjusting conveying pipe furthest from the outlet also connected to the electrolyte storage tank. A three-way control valve 707 is installed at the three-way connection point of the three-way connecting pipe. A pH sensor is installed inside the adjusting conveying pipe.

[0133] One real-time method for a solution conveying mechanism includes adjusting the conveying pipe, adjusting the connection between one end of the conveying pipe and the outlet, and adjusting the connection between the end of the conveying pipe furthest from the outlet and a connection such as... Figure 8 The zirconium salt solution pretreatment mechanism 702 shown has an electrolyte storage tank outside it. The electrolyte storage tank and the zirconium salt solution pretreatment mechanism are connected to the electrolytic cell through a three-way connecting pipe. A three-way control valve is provided at the three-way connection of the three-way connecting pipe.

[0134] Zirconium salt solution pretreatment mechanism includes, for example Figure 11 The pretreatment chamber 7022 shown has two sets of partitions 7024 arranged side-by-side inside, dividing the interior of the pretreatment chamber into a raw material chamber 70221, a first mixing chamber 70222, and a second mixing chamber 70223. A mixing and stirring rod 7028 is rotatably mounted in both the raw material chamber and the first mixing chamber within the pretreatment chamber. A solution outlet 7029 is located at the upper end of the partition, above the mixing and stirring rod. A filter screen 7020 is installed at the solution outlet, and an inverted U-shaped solution barrier 7025 partially surrounds the filter screen. A mechanism protective cover 7023 is located above the pretreatment chamber, with a guide groove 7026 on the cover. The inverted U-shaped solution barrier slidably fits within the guide groove. A push-out cylinder 7027 is installed on the mechanism protective cover, and the inverted U-shaped solution barrier is connected to the push-out end of the push-out cylinder. The zirconium salt solution pretreatment mechanism includes an axial lifting mechanism 711, which is located outside the pretreatment chamber, and a protective cover is installed at the lifting end of the axial lifting mechanism.

[0135] The mixing impeller includes, for example, Figure 15 The stirring rod body 70281 shown is rotatably mounted within the pretreatment chamber. A drive motor 70283 is installed on the pretreatment chamber, with its drive end connected to one end of the stirring rod body. The stirring rod body is provided with multiple stirring blades 70284 distributed along its length. The stirring blades include, for example... Figure 16 The stirring blade body 70284a shown is mounted on the stirring rod body, and a set of... Figure 17The shown stirring blade 70284b has a guide plate 70284c protruding from its surface. Grooves are provided on both opposite sides of the guide plate. A rear sleeve 708 is fitted onto the end of the stirring rod body furthest from the drive motor, and multiple tail stirring blades 710a are arranged circumferentially on the outer periphery of the rear sleeve. A front sleeve 709 is located on the stirring rod body near the drive motor, and multiple front stirring blades 710b are arranged circumferentially on the outer periphery of the front sleeve, with the front stirring blades located within the raw material chamber.

[0136] One real-time method for a solution conveying mechanism includes adjusting a conveying pipe, adjusting the connection of one end of the conveying pipe to a discharge port, and adjusting the external features of the conveying pipe as shown in the image. Figure 9 The electrolyte pretreatment mechanism 703 shown is connected to the electrolytic cell via a three-way connecting pipe at the end of the adjusting conveying pipe away from the discharge port. A three-way control valve is provided at the three-way connection of the three-way connecting pipe. The input end of the electrolyte pretreatment mechanism is connected to an electrolyte storage tank via an electrolyte conveying pipe 705.

[0137] The electrolyte pretreatment mechanism includes a pretreatment chamber, a mixing and stirring rod that rotates inside the pretreatment chamber, and a conductivity meter installed inside the pretreatment chamber.

[0138] One real-time method of the solution delivery mechanism includes adjusting the delivery pipeline, one end of which is connected to the outlet, and the end of the delivery pipeline away from the outlet is connected to a zirconium salt solution pretreatment mechanism. An electrolyte pretreatment mechanism is provided outside the zirconium salt solution pretreatment mechanism. The electrolyte pretreatment mechanism and the zirconium salt solution pretreatment mechanism are connected to an electrolytic cell through a three-way connecting pipe. A three-way control valve is provided at the three-way connection of the three-way connecting pipe. The input end of the electrolyte pretreatment mechanism is connected to an electrolyte storage tank through an electrolyte delivery pipe.

[0139] The working principle of the device of the present invention is as follows:

[0140] The frame 100 integrates a solvent mixing cylinder 300 and an electrolysis chamber 200, reducing the equipment footprint and facilitating assembly line operation. The rigid frame also reduces vibration interference and ensures the stability of the electrolysis process. The frame can be made of 304 stainless steel. The zirconium salt solution is directly ultrasonically treated within the solvent mixing cylinder, avoiding secondary contamination or agglomeration caused by transfer. Ultrasonic cavitation also effectively promotes uniform mixing of the zirconium salt with complexing agents, dispersants, and other additives, improving the homogeneity of the precursor solution. The solution delivery mechanism 700 uses a pump or gravity flow to deliver the mixed solution... The solution is precisely introduced into the electrolytic cell with controllable delivery, avoiding errors from manual operation. A corrosion-resistant peristaltic pump is installed on the adjustment delivery pipe 701 of the solution delivery mechanism. The adjustment delivery pipe uses PTFE piping, which effectively prevents metal ion contamination of the delivered solution. A bipolar electrode structure is adopted, which reduces energy consumption by approximately 15% compared to traditional unipolar electrolysis. The first electrode segment 901 corresponds to the anode chamber of the electrolytic cell 204, oxidizing Zr⁴⁺ to ZrO₂ while simultaneously releasing oxygen: 4OH⁻ → O₂↑ + 2H₂O + 4e⁻. - The second electrode segment 902 corresponds to the cathode chamber inserted into the electrolytic cell, reducing H2O to produce hydrogen: 2H2O + 2e- - →H2↑+2OH-, enabling co-production of hydrogen and zirconium; conductive connector 903 ensures stable potential difference between the two electrode sections, avoiding uneven current distribution; the anode and cathode chambers in the electrolytic cell are partitioned to prevent H2 from entering the anode area and affecting ZrO2 purity, avoiding cross-contamination of products; the entire process adopts ultrasonic solvent mixing → bipolar electrode electrolysis → product collection, which is fully enclosed and controllable, suitable for continuous production; the byproduct OH- from water electrolysis for hydrogen production can be recycled for pH adjustment, enabling resource utilization; a pH sensor and viscometer are installed in the solvent mixing cylinder, and pH, temperature, and current sensors are installed in each electrolysis chamber.

[0141] The stirring motor 600 drives the stirring shaft 501 to rotate, and in conjunction with the extension and retraction of the electric telescopic rod, achieves three-dimensional stirring, avoiding solution stratification or localized uneven concentration, and achieving efficient mixing. A sealed bearing made of PTFE is installed at the rotating connection between the stirring shaft and the solvent mixing cylinder 300. The cross-shaped layout creates turbulence, enhancing the mechanical breaking up of zirconium salt agglomerates and improving dispersibility. This ensures full-area mixing within the cylinder, especially for high-concentration solutions such as 60% Zr salt, where stirring performance is even better. The inner spiral guide plate 504 and the outer spiral guide plate 505 form a double spiral structure, creating a composite axial and radial flow field within the cylinder, accelerating the diffusion of additives. The spiral plates convert rotational kinetic energy into laminar shear force, which... Reduced motor power consumption; the transparent observation window 304 is made of high borosilicate glass, allowing for direct observation of the solution mixing state, such as whether it is uniform and whether there is precipitation, facilitating timely parameter adjustment and preventing fluctuations in the performance of subsequent electrolytic products due to uneven mixing; the feed inlet 301 is located at the top of the solvent mixing cylinder, and the discharge outlet 302 is located at the bottom of the solvent mixing cylinder. The feed inlet can be connected to an automatic feeder, and the discharge outlet is delivered by a peristaltic pump to achieve continuous production, which can appropriately reduce manual intervention; a screen is installed at the discharge outlet to effectively prevent undissolved particles from entering the electrolytic cell 204; the reactant storage chamber 303 is linked to an electric telescopic rod, which can release pH adjusters or dispersants and other additives as needed during stirring, achieving precise addition and improving mixing efficiency; Reagents can be added without interrupting stirring, reducing downtime and making it suitable for continuous production. The flexible separator 8021 controls reagent flow through contraction and expansion, achieving precise addition, such as controlling the dropping rate of pH adjusters to 0.1 mL / s. The elastic closure design also prevents backflow of mixed solutions and contamination of the reagent storage chamber. The linkage design between the reagent addition system and the stirring components results in a high level of automation. The stroke of the electric telescopic rod and the opening and closing of the umbrella frame are controlled by PLC logic. The extension and retraction of the electric telescopic rod are transmitted through the main shaft 8023 of the support, driving the umbrella frame to open the flexible separator layer, achieving automated addition with good mechanical linkage effect. The reagent release rate matches the stirring intensity, and the addition amount increases accordingly at high speeds. The docking accuracy between the main shaft and the electric telescopic rod is ≤0.1mm; perfluoropolyether oil is added to the rolling part of the steel ball roller 8011 and the arc groove 8012; the fan-shaped partition plate is completely sealed when closed and forms a uniform channel when opened, which can avoid local blockage when adding additives; the support arm 8028 is hinged by the ear plate to realize synchronous opening and closing, ensuring uniform release of reagents. The overall design is similar to a petal valve, which has a good additive addition effect; the transparent window 205 is made of high borosilicate glass, which can observe the electrolysis status in real time, such as bubble precipitation and electrode deposition, and adjust parameters in time. If an abnormality is found, such as electrode corrosion or solution discoloration, the machine can be stopped immediately; the side of the transparent window located inside the electrolytic cell is coated with an anti-corrosion film.

[0142] The electrolyte is controlled by a three-way control valve 707 to either directly enter the electrolytic cell 204 or temporarily stored in the electrolyte storage tank 706. This is suitable for small-scale intermittent production, is simple and direct, and has low cost, requiring only pipes, valves, and storage tanks, resulting in low equipment investment. The three-way control valve can be a pneumatic butterfly valve. An integrated zirconium salt solution pretreatment mechanism 702 can remove undissolved particles or adjust dispersion, improving electrolyte homogeneity. The three-way control valve allows for selection of direct delivery to the electrolytic cell or pretreatment, offering flexible switching to adapt to different process requirements. The electrolyte storage tank temporarily stores the raw electrolyte, while the electrolyte pretreatment mechanism 703 independently performs pH adjustment or temperature control before being delivered to the electrolytic cell via the three-way control valve. This provides high process controllability, separating electrolyte pretreatment from electrolysis, and the independent electrolyte pretreatment mechanism facilitates individual optimization. The parameters for each stage, such as the pretreatment pH of 8-10 and the specific electrolysis pH of 7-8; the composite pretreatment of zirconium salt solution pretreatment and electrolyte pretreatment provides double protection. The zirconium salt solution pretreatment mechanism solves the dispersion problem (e.g., ultrasonic breaking of agglomerates), and the electrolyte pretreatment mechanism adjusts the physicochemical properties, such as conductivity and temperature; a three-way control valve provides an emergency bypass, so that production can still be maintained if a pretreatment fails; suitable for large-scale production of high-purity nano ZrO2; a stepped mixing method, the raw material chamber 70221 is used for initial dispersion of zirconium salt agglomerates, the first mixing chamber 70222 adds additives, such as complexing agents, for homogenization, and the second mixing chamber 70223 finely adjusts the pH or temperature to ensure solution stability. The partition physically isolates the reactions at each stage to avoid backmixing and prevent untreated solutions from contaminating the finished product.Employing a three-chamber structure: a high-speed shearing raw material chamber → a gentle stirring first mixing chamber → a static mixing second mixing chamber; a filter screen 7020 effectively intercepts undissolved particles; an inverted U-shaped solution baffle 7025 guides the solution to overflow from above the filter screen, preventing direct impact that could deform it; the semi-enclosed structure reduces splashing and keeps the chamber clean; an ejector cylinder 7027 automatically raises and lowers the inverted U-shaped solution baffle, facilitating filter screen replacement or cleaning without stopping the machine; the ejector cylinder's pushing speed is adjustable from 5cm / s to 10cm / s, preventing solution disturbance; automated design improves maintenance efficiency; the drive motor 70283 is directly connected to the stirring rod body 70281, providing stable torque; the integrated design reduces... Fewer transmission components reduce the failure rate; the main body of the stirring blade 70284a provides basic shearing action to break up zirconium salt agglomerates; the stirring blade 70284b forms a bidirectional vortex, improving the radial mixing efficiency of the solution and shortening the mixing time by 30%; the guide plate 70284c enhances local mass transfer; the tail stirring blade 710a at the rear sleeve 708 provides end-stage enhanced stirring; the rear sleeve also offsets the load at the front end of the stirring rod, reducing bearing wear; the front stirring blade 710b at the front sleeve 709 is located in the high-solids-content raw material chamber and adopts a 45° large inclination angle design to enhance shear force; the front sleeve also protects the drive end bearing from particle impact; the guide plate groove and the bidirectional stirring blade form a three-dimensional flow field, resulting in better stirring and mixing effect.

Claims

1. A method for preparing highly dispersed nano-zirconia for hydrogen production via water electrolysis, characterized by: Including the following step, (S01) Take an appropriate amount of zirconium salt solution and adjust the pH value of the zirconium salt solution to 8-10; (S02) The zirconium salt solution after pH adjustment in step (S01) is introduced into an electrolytic cell for ultrasonication; (S03) The zirconium salt solution in step (S02) is electrolyzed in stages by heating through bipolar electrodes in an electrolytic cell; (S04) After the electrolysis is completed (S03), the product in the electrolytic cell is dried and calcined to obtain nano-zirconia.

2. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: The zirconium salt solution in step (S01) is prepared by mixing zirconium salt with a deionized aqueous solvent; the zirconium salt in step (S01) is selected from one or more of zirconium sulfate or zirconium nitrate; the pH value of the zirconium salt solution in step (S01) is adjusted by a surface additive; the surface additive is an amine-containing organic compound; the amine-containing organic compound is selected from one or more of ethylenediamine, triethylamine, and tetramethylethylenediamine.

3. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: The zirconium salt solution in step (S01) contains a dispersant and a stabilizer; the dispersant is selected from one or more of polyethylene glycol, polyvinyl alcohol, polymethyl methacrylate or sodium polystyrene sulfonate; the stabilizer is a combination of sodium dodecyl sulfate and polyelectrolyte; the molar ratio of the dispersant, stabilizer and zirconium salt in the zirconium salt solution is 3-10:8-25:

1.

4. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: The zirconium salt solution to be introduced into the electrolytic cell in step (S01) is centrifuged to obtain the supernatant, and the supernatant is introduced into the electrolytic cell in step (S02); the centrifugation speed is 3000 rpm to 5000 rpm; the ultrasonic frequency in step (S02) is 20 kHz to 40 kHz; the ultrasonic time in step (S02) is 25 min to 45 min; the molar ratio of zirconium ions to electrolyte in the electrolytic cell in step (S02) is 1:0.1 to 0.3; the electrolyte in the electrolyte solution in the electrolytic cell in step (S02) is selected from sodium sulfate or potassium nitrate, or a mixture of both.

5. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: The zirconium salt solution after ultrasonic treatment in step (S02) undergoes pretreatment, including the following steps: (S02-A1) After adding an appropriate amount of complexing agent to the zirconium salt solution, mix thoroughly with a stirrer; (S02-A2) The zirconium salt solution after mixing in step (S02-A1) is filtered through a filter membrane to remove insoluble matter and impurities.

6. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: in Step (S02) The preparation of the electrolyte in the electrolytic cell includes the following steps: (S02-B1) An initial electrolyte containing deionized water and a buffer is prepared in the electrolytic cell; (S02-B2) Add an appropriate amount of electrolyte to the initial electrolyte solution in step (S02-B1); (S02-B3) Add a conductivity enhancer equivalent to 20% to 50% of the amount of buffer added to the electrolyte in step (S02-B2); (S02-B4) Add a surfactant equivalent to 1% to 3% of the amount of buffer added to the electrolyte in step (S02-B3), and mix thoroughly using a stirrer.

7. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 6, characterized in that: The buffer in step (S02-B1) is sodium dihydrogen phosphate; the conductivity enhancer in step (S02-B3) is selected from one or more of potassium nitrate or potassium sulfate; the surfactant in step (S02-B4) is selected from one or more of sodium dodecyl sulfate, polysorbate, or octylbenzyl alcohol.

8. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 10, characterized in that: The segmented heating electrolysis temperature range in step (S03) is 25℃~45℃; The segmented heating in step (S03) is as follows: (S03-1) Before starting electrolysis, adjust the temperature of the electrolyte in the electrolytic cell to 25°C; (S03-2) The electrolyte temperature from step (S03-1) is gradually increased to 35°C at a rate of 0.5°C to 2.5°C per minute; (S03-3) When the electrolyte reaches the first stage temperature of 35°C, maintain the first stage temperature and continue electrolysis for 10 to 15 minutes. (S03-4) After the electrolysis in step (S03-3) is completed, continue to raise the electrolyte temperature to the final working temperature of 45°C at a rate of 0.5°C to 2.5°C per minute; (S03-5) Continue to maintain the electrolyte at the final working temperature reached in step (S03-4) for 30 to 80 minutes.

9. The method for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to claim 1, characterized in that: The drying in step (S04) is vacuum drying or freeze drying; the vacuum drying temperature is 50℃~70℃; the vacuum drying time is 8h~16h; the freeze drying temperature is -60℃~-40℃; the freeze drying time is 12h~36h; the calcination temperature in step (S04) is 300℃~700℃; the calcination time in step (S04) is 2h~4h; the average particle size of the nano-zirconia in step (S04) is 10~50 nm; the dielectric constant of the nano-zirconia in step (S04) at 20kHz is 38~42, and the electrical loss tangent is 0.0015~0.0025; in step (S04), the product collected in the electrolytic cell is washed through a ceramic membrane.

10. The apparatus for preparing highly dispersed nano-zirconia for hydrogen production by water electrolysis according to any one of claims 1-9, characterized in that: The device includes a frame (100), on which a solvent mixing cylinder (300) and an electrolysis chamber (200) are provided; the solvent mixing cylinder is connected to the electrolysis chamber via a solution delivery mechanism (700); an ultrasonic generator is provided inside the solvent mixing cylinder; an electrolysis cell (204) is provided inside the electrolysis chamber, and the solvent mixing cylinder is connected to the electrolysis cell via the solution delivery mechanism; a bipolar electrode (206) is provided at the bottom of the electrolysis cell; the bipolar electrode includes an electrode body (900), on which a first electrode segment (901) and a second electrode segment (902) are connected via a conductive connector (903), and the first electrode segment and the second electrode segment are inserted into the anode chamber and cathode chamber of the electrolysis cell respectively.

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