Method for preparing hydroxyl gallium oxide in short process

Abstract

The invention provides a method for preparing hydroxyl gallium oxide in a short process, and belongs to the field of nonferrous metallurgy. The method comprises the following steps: dissolving gallium nitrate in deionized water to obtain a gallium nitrate solution with set concentration; placing the gallium nitrate solution under a high-power gravity field so that gallium nitrate in the gallium nitrate solution and deionized water are subjected to a conversion reaction to obtain a mixed solution containing hydroxyl gallium oxide; and carrying out solid-liquid separation and drying on the mixed solution to obtain the hydroxyl gallium oxide powder. Under the action of a high-power gravity field, the gallium nitrate aqueous solution is highly dispersed, highly turbulent, strongly mixed and rapidly updated in interface, and the reaction between gallium ions and water molecules is directly in an activated state, so that the reaction rate is promoted to be increased, and rapid and efficient conversion of hydroxyl gallium oxide is realized; meanwhile, water molecules are subjected to intense mutual collision and strong friction to generate a large amount of heat, so that the temperature of the system is quickly increased, and the heat intensity of the reaction is high, thereby improving the production efficiency of the hydroxyl gallium oxide.

Description

Technical Field

[0001] This application relates to the technical field of non-ferrous metal metallurgy, and particularly relates to a method for preparing gallium oxyhydroxide by a short process. Background Art

[0002] Gallium oxide (Ga2O3), as a new type of ultra-wide bandgap semiconductor material, has a bandgap width of more than 4.9 eV, which is much higher than that of silicon carbide and gallium nitride. It has characteristics such as high voltage resistance, high temperature resistance, and radiation resistance. Its breakdown electric field is about 8 MV / cm, which is 2.5 times that of gallium nitride and more than 3 times that of silicon carbide, and is suitable for high-power devices. In addition, it also has advantages such as a higher absorption coefficient, high carrier mobility, and low manufacturing cost, and has been widely studied in the fields of high-power radio frequency devices, power electronics, solar-blind ultraviolet photodetectors, solar cells, etc. Due to its excellent performance and broad application prospects in semiconductor technology, Ga2O3 semiconductor materials have attracted extensive attention in the academic community. Gallium oxyhydroxide (GaOOH), as a key precursor material for preparing gallium oxide, can be calcined at high temperature to obtain gallium oxide. Therefore, preparing qualified gallium oxyhydroxide is a key step in the production of gallium oxide.

[0003] In the prior art, the application case with Chinese patent application number 201711418839.7 discloses a method for preparing gallium oxyhydroxide from metallic gallium. First, nitric acid reacts with metallic gallium to obtain a gallium nitrate solution, and then the pH value of the solution is adjusted by dropping an alkali solution for neutralization. Gallium oxyhydroxide powder is obtained through chemical precipitation and aging. The application case with Chinese patent number 202010436819.8 discloses a method for preparing gallium oxyhydroxide from metallic gallium. Nitric acid reacts with metallic gallium to obtain a gallium nitrate solution, and then surfactants such as dodecyl sulfonic acid are added. After that, the pH of the solution is adjusted by dropping an alkali solution, and gallium oxyhydroxide powder is obtained through precipitation and aging. The application case with Chinese patent number 202410934702.0 discloses a method for preparing high-purity gallium oxide by microwave digestion. Metallic gallium and hydrogen peroxide are added to a microwave digestion tank filled with high-purity water and placed in a microwave digester in a high-temperature and high-pressure environment. A magnetic stirrer is used, and under the action of microwave, metallic gallium is completely converted into gallium hydroxide, and then high-purity gallium oxide is obtained through filtration, washing, drying, and high-temperature roasting. The Chinese patent document with publication number CN102976393B discloses a method for preparing gallium oxyhydroxide nanocrystals. An 8-fold volume of benzene is used to dilute a benzene-saturated solution of gallium chloride, and then methanol is added to form a mixed solution. Then, the mixed solution is placed in a high-pressure reaction kettle and reacted at 160 - 200 °C for 12 - 48 h, and finally, powdery gallium oxyhydroxide nanocrystals are obtained. The Chinese patent document with publication number CN102786078B discloses a method for preparing gallium oxyhydroxide nanocrystals. First, a benzene-saturated solution of gallium chloride is diluted with benzene, and then an aqueous solution of cetyltrimethylammonium bromide in deionized water is dropped. After that, the mixed solution is placed in a high-pressure reaction kettle and reacted at 160 - 200 °C for 10 - 18 h, and finally, gallium oxyhydroxide nanocrystals are obtained. The application case with Chinese patent application number 201210542115.4 discloses an electrochemical method for preparing gallium oxyhydroxide. Using metallic gallium as the anode, three-stage electrolysis is carried out in an alkaline electrolyte to convert metallic gallium into a sodium gallate solution, and then gallium oxyhydroxide is precipitated by adjusting the pH value of the solution. In summary, the existing methods for preparing gallium oxyhydroxide generally have problems such as long process flow and large reagent consumption, and there is still a large room for optimization. Therefore, it is necessary to continue to develop a more green, efficient, short-process, and low-cost process technology for preparing gallium oxyhydroxide to provide guarantee for the sustainable development of the semiconductor industry. Summary of the Invention

[0004] The present application provides a method for preparing gallium oxyhydroxide with a short process to solve the following technical problem: how to improve the production efficiency of gallium oxyhydroxide.

[0005] The embodiment of the present application provides a method for preparing gallium oxyhydroxide with a short process, and the method includes:

[0006] Dissolve gallium nitrate in deionized water to obtain a gallium nitrate solution with a set concentration;

[0007] Place the gallium nitrate solution under a high-gravity field to cause a conversion reaction between the gallium nitrate and deionized water in the gallium nitrate solution, obtaining a mixture containing gallium oxyhydroxide;

[0008] Perform solid-liquid separation and drying on the mixture to obtain gallium oxyhydroxide powder.

[0009] Optionally, the set concentration is 0.05 mol / L to 5 mol / L.

[0010] Optionally, the device for generating the high-gravity field is a high-gravity reactor.

[0011] Optionally, the material of the high-gravity reactor is Hastelloy, titanium material or stainless steel.

[0012] Optionally, the rotation speed of the high-gravity reactor is 1000 r / min to 3000 r / min.

[0013] Optionally, the reaction temperature of the conversion reaction is 120°C to 260°C, and the reaction time of the conversion reaction is 0.5 h to 20 h.

[0014] Optionally, the filter residue obtained from the solid-liquid separation is washed 3 to 10 times with deionized water.

[0015] Optionally, the drying temperature is 90°C to 160°C, and the drying time is 4 h to 48 h.

[0016] Optionally, the conversion rate of gallium nitrate to gallium oxyhydroxide is ≥99.5%.

[0017] Optionally, the purity of the gallium oxyhydroxide powder is ≥99.995%.

[0018] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the prior art:

[0019] An embodiment of the present application provides a method for preparing gallium oxyhydroxide by a short process. The method includes: dissolving gallium nitrate in deionized water to obtain a gallium nitrate solution with a set concentration; placing the gallium nitrate solution under a high-gravity field to cause a conversion reaction between gallium nitrate and deionized water in the gallium nitrate solution, obtaining a mixed solution containing gallium oxyhydroxide; and performing solid-liquid separation and drying on the mixed solution to obtain gallium oxyhydroxide powder. By placing the gallium nitrate solution under a high-gravity field for reaction, on the one hand, under the action of the high-gravity field, the high dispersion, high turbulence, strong mixing, and rapid interface renewal of the gallium nitrate aqueous solution are achieved, making the reaction between gallium ions and water molecules directly in an activated state, thereby promoting the improvement of the reaction rate and realizing the rapid and efficient conversion of gallium oxyhydroxide; on the other hand, under the action of the high-gravity field, intense collisions occur between water molecules, and a large amount of heat is generated by strong friction, causing the system to rapidly heat up, with a high heat intensity of the reaction, thereby improving the production efficiency of gallium oxyhydroxide. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings herein are incorporated into and constitute a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic flow chart of a method for preparing gallium oxyhydroxide by a short process provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0024] The various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the present application; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and individual numbers within the range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0025] In addition, in the description of the specification of the present application, terms such as "including" and "comprising" mean "including but not limited to". In this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this text, "and / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Where A and B can be singular or plural. In this text, "at least one" means one or more, and "a plurality" means two or more. "At least one kind", "at least one of the following items (pieces)" or similar expressions refer to any combination of these items, including any combination of single items (pieces) or plural items (pieces). For example, "at least one of a, b, or c", or, "at least one of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively. The "parts representation method" such as parts by weight and parts by mass represents the proportional relationship between each component. In the proportional relationships involved in this text, the parameters that need to be described by proportion should be understood as the antecedents of the proportion formula in the order of description, and the proportional numbers should be understood as the consequents of the proportion formula. For example, if the mass ratio of substance A, substance B, and substance C is 1:2:3, then substance A, substance B, and substance C should correspond one by one with the proportional numbers in the proportion formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0026] Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment, etc. used in the present application can be obtained through market purchase or can be prepared by existing methods.

[0027] Figure 1 It is a schematic flow diagram of a method for preparing gallium oxyhydroxide with a short process provided for the embodiments of the present application.

[0028] As shown Figure 1 in the figure, the present application provides a method for preparing gallium oxyhydroxide by a short process, and the method includes:

[0029] S1. Dissolve gallium nitrate in deionized water to obtain a gallium nitrate solution with a set concentration;

[0030] In some embodiments, the set concentration is 0.05 mol / L to 5 mol / L.

[0031] The concentration directly affects the reaction rate and product purity. When the concentration is lower than 0.05 mol / L, the reaction rate decreases due to insufficient molecular collisions; when the concentration is higher than 5 mol / L, non-uniform nucleation occurs due to local supersaturation, affecting the crystallinity and dispersibility of gallium oxyhydroxide. Exemplarily, the concentration of the gallium nitrate solution can be 0.05 mol / L, 0.1 mol / L, 0.5 mol / L, 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, 5 mol / L, etc.

[0032] S2. Place the gallium nitrate solution under a high-gravity field to cause a conversion reaction between gallium nitrate and deionized water in the gallium nitrate solution, obtaining a mixed solution containing gallium oxyhydroxide;

[0033] In some embodiments, the generating device of the high-gravity field is a rotating packed bed reactor.

[0034] It should be noted that a rotating packed bed reactor is a chemical engineering device that generates a strong centrifugal force field (up to hundreds to thousands of times the earth's gravity) through high-speed rotation, and is used to intensify the transfer, mixing, and reaction processes of multiphase flows. Its core principle is to break the mass transfer limitation under the traditional gravity field by using the centrifugal force field, and accelerate the contact efficiency between molecules through high dispersion, high turbulence, and strong shear force, thereby shortening the reaction time and improving the product purity.

[0035] The main components of a rotating packed bed reactor include: a rotating rotor: the core component, usually a porous packing or a disc structure, with a rotation speed of 1000 - 3000 r / min, generating a high-gravity environment. A gas-liquid distribution system: optimizing the countercurrent or co-current contact path of gas and liquid to ensure uniform dispersion. A jacket and temperature control system: some reactors are equipped with a jacket inner liner to control the temperature through a circulating medium.

[0036] In some embodiments, the material of the rotating packed bed reactor is Hastelloy, titanium, or stainless steel.

[0037] The material of the rotating packed bed reactor being Hastelloy, titanium, or stainless steel can withstand the strong mechanical shear force under the high-gravity field and the high-temperature corrosion environment of the reaction system.

[0038] In some embodiments, the rotational speed of the high-gravity reactor is 1000 r / min to 3000 r / min.

[0039] The rotational speed determines the centrifugal acceleration (equivalent gravity multiple), which directly affects the mixing efficiency and reaction kinetics. Limiting the rotational speed of the high-gravity reactor to 1000 r / min to 3000 r / min can generate strong turbulence and interface renewal, promote the full contact between gallium ions and water molecules, and shorten the reaction time. Exemplarily, the rotational speed of the high-gravity reactor can be 1000 r / min, 1200 r / min, 1500 r / min, 2000 r / min, 2500 r / min, 2800 r / min, 3000 r / min, etc.

[0040] In some embodiments, the reaction temperature of the conversion reaction is 120°C to 260°C, and the reaction time of the conversion reaction is 0.5 h to 20 h.

[0041] In the embodiments of the present application, by reacting the gallium nitrate solution in a high-gravity field, on the one hand, under the action of the high-gravity field, the high dispersion, high turbulence, strong mixing and rapid interface renewal of the gallium nitrate aqueous solution are achieved, so that the reaction between gallium ions and water molecules will be directly in an activated state, thereby promoting the improvement of the reaction rate and realizing the rapid and efficient conversion of gallium hydroxide oxide; on the other hand, under the action of the high-gravity field, intense collisions occur between water molecules, and a large amount of heat is generated by strong friction, causing the system to heat up rapidly, and the heat intensity of the reaction is high. Exemplarily, the reaction temperature of the conversion reaction can be 120°C, 150°C, 180°C, 200°C, 220°C, 260°C, etc., and the reaction time of the conversion reaction can be 0.5 h, 2 h, 4 h, 8 h, 15 h, 20 h, etc.

[0042] S3. Perform solid-liquid separation and drying on the mixed solution to obtain gallium hydroxide oxide powder.

[0043] In some embodiments, the filter residue obtained by the solid-liquid separation is washed 3 to 10 times with deionized water.

[0044] Multiple washings can remove adsorbed nitrate ions and unreacted impurities to ensure the product purity.

[0045] In some embodiments, the drying temperature is 90°C to 160°C, and the drying time is 4 h to 48 h.

[0046] Limiting the drying temperature to 90°C to 160°C can retain the crystalline structure of gallium hydroxide oxide and prevent dehydration to form gallium oxide. Exemplarily, the drying temperature can be 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 160°C, etc., and the drying time can be 4 h, 8 h, 16 h, 30 h, 35 h, 45 h, 48 h, etc.

[0047] In some embodiments, the conversion rate of gallium nitrate to gallium oxyhydroxide is ≥99.5%.

[0048] In some embodiments, the purity of the gallium oxyhydroxide powder is ≥99.995%.

[0049] This application uses gallium nitrate and water as raw materials, and under the action of a high-gravity field, gallium oxyhydroxide powder can be rapidly and efficiently prepared through a one-step reaction. It has the advantages of high reaction efficiency and short process flow. Moreover, no chemical reagents such as acids and alkalis are consumed during the reaction process, which can not only effectively reduce the raw material cost, but also minimize the risk of impurities introduced by raw materials, facilitating the obtaining of high-purity products.

[0050] Therefore, a method for preparing gallium oxyhydroxide with a short process flow provided by the embodiments of this application has the following advantages:

[0051] (1) The process flow is significantly simplified: Only gallium nitrate and deionized water are required as raw materials, and the hydrolysis conversion is directly completed in a high-gravity reactor, eliminating the acid-base adjustment, high-temperature oxidation or complex post-treatment steps in the traditional process (such as multiple pH adjustments required in the sol-gel method and multiple steps required for the oxidation of metallic gallium). At the same time, no acids, alkalis or organic solvents need to be added, reducing the risk of impurity introduction, and lowering the raw material cost and environmental protection pressure.

[0052] (2) The reaction efficiency and conversion rate are greatly improved: The high turbulence and strong shear force generated by a high-gravity field (1000 - 3000 r / min) accelerate molecular mass transfer, shortening the reaction time to 0.5 h - 20 h, and the efficiency is increased by several times compared with the traditional hydrothermal method (several days). At the same time, the combined action of the centrifugal friction self-heating effect and external temperature control (120 - 260 °C) reduces the activation energy, achieving a conversion rate of gallium nitrate ≥99.5% and high product purity.

[0053] (3) The product quality and cost advantages are prominent: The high-gravity field inhibits non-uniform nucleation caused by local supersaturation, ensuring excellent crystallinity and dispersibility of the gallium oxyhydroxide powder, and avoiding problems such as insufficient crystallinity or particle agglomeration in the traditional method.

[0054] (4) Environmental friendliness and sustainability: There are no harmful by-products during the reaction process, and the washing wastewater only contains nitrate ions, which is simple to treat and meets the goal of green manufacturing. At the same time, the utilization rate of gallium nitrate raw materials is high, and the amount of waste generated is extremely small. Compared with the metallic gallium oxidation method, the raw material loss is reduced by more than 30%.

[0055] In summary, through the multi-field collaborative enhancement (mass transfer, thermodynamics, kinetics) of the high-gravity technology, the present method realizes the efficient, low-cost, and short-process preparation of gallium oxyhydroxide, and solves the pain points such as long reaction cycle, high energy consumption, and insufficient product purity in the traditional process. Its technical advantages highly coincide with the industrialization requirements of gallium oxide semiconductor materials, providing a reliable precursor preparation scheme for the large-scale application of the new generation of power devices.

[0056] The following will further elaborate on the present application in combination with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. For the experimental methods without specific conditions noted in the following embodiments, they are usually determined according to industry standards. If there is no corresponding industry standard, they are carried out according to general international standards, conventional conditions, or the conditions recommended by the manufacturer.

[0057] Example 1

[0058] This example provides a method for efficiently and short-process preparing gallium oxyhydroxide, which specifically includes the following steps:

[0059] (1) Gallium nitrate is added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 0.05 mol / L;

[0060] (2) The gallium nitrate solution is placed in a high-gravity reactor, the high-gravity reactor is started, its rotation speed is adjusted to 1000 r / min, and the reaction is carried out at a temperature of 120 °C for 18 h, so that gallium nitrate and water directly react under a high-magnitude gravity field and are converted into gallium oxyhydroxide in one step;

[0061] (3) After the reaction is completed, it is cooled to room temperature, and then the obtained slurry is subjected to solid-liquid separation, and the obtained filter residue is washed 3 times with deionized water;

[0062] (4) The washed filter residue is dried at a temperature of 100 °C for 36 h to obtain a gallium oxyhydroxide powder material.

[0063] Using the treatment method of this example, the obtained gallium oxyhydroxide powder is weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results show that the conversion rate of gallium nitrate to gallium oxyhydroxide is 99.63%, and the purity of gallium oxyhydroxide is 99.9906%.

[0064] Example 2

[0065] This example provides a method for efficiently and short-process preparing gallium oxyhydroxide, which specifically includes the following steps:

[0066] (1) Gallium nitrate is added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 5 mol / L;

[0067] (2) Place the gallium nitrate solution in a high-gravity reactor, start the high-gravity reactor, adjust its rotation speed to 3000 r / min, and react for 1 h at a temperature of 240 °C, so that gallium nitrate and water directly react under a high-magnitude gravity field to be converted into gallium oxyhydroxide in one step;

[0068] (3) After the reaction, cool to room temperature, then perform solid-liquid separation on the obtained slurry, and wash the obtained filter residue 10 times with deionized water;

[0069] (4) Dry the washed filter residue at a temperature of 160 °C for 4 h to obtain gallium oxyhydroxide powder material.

[0070] Using the treatment method of this example, weigh the obtained gallium oxyhydroxide powder and analyze it by inductively coupled plasma mass spectrometer (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 99.65%, and the purity of gallium oxyhydroxide is 99.9953%.

[0071] Example 3

[0072] This example provides a method for efficiently and short-process preparing gallium oxyhydroxide, which specifically includes the following steps:

[0073] (1) Add gallium nitrate to deionized water and dissolve it in deionized water to obtain a gallium nitrate solution with a concentration of 2 mol / L;

[0074] (2) Place the gallium nitrate solution in a high-gravity reactor, start the high-gravity reactor, adjust its rotation speed to 1500 r / min, and react for 12 h at a temperature of 150 °C, so that gallium nitrate and water directly react under a high-magnitude gravity field to be converted into gallium oxyhydroxide in one step;

[0075] (3) After the reaction, cool to room temperature, then perform solid-liquid separation on the obtained slurry, and wash the obtained filter residue 6 times with deionized water;

[0076] (4) Dry the washed filter residue at a temperature of 120 °C for 24 h to obtain gallium oxyhydroxide powder material.

[0077] Using the treatment method of this example, weigh the obtained gallium oxyhydroxide powder and analyze it by inductively coupled plasma mass spectrometer (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 99.83%, and the purity of gallium oxyhydroxide is 99.9965%.

[0078] Example 4

[0079] This example provides a method for efficiently and short-process preparing gallium oxyhydroxide, which specifically includes the following steps:

[0080] (1) Gallium nitrate was added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 3 mol / L;

[0081] (2) The high-gravity reactor was started, and its rotation speed was adjusted to 2000 r / min. The reaction was carried out at a temperature of 180 °C for 10 h, so that gallium nitrate and water directly reacted under a high-gravity field and were converted into gallium oxyhydroxide in one step;

[0082] (3) After the reaction, it was cooled to room temperature, and then the obtained slurry was subjected to solid-liquid separation. The obtained filter residue was washed 6 times with deionized water;

[0083] (4) The washed filter residue was dried at a temperature of 140 °C for 10 h to obtain gallium oxyhydroxide powder material.

[0084] Using the treatment method of this example, the obtained gallium oxyhydroxide powder was weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the conversion rate of gallium nitrate to gallium oxyhydroxide was 99.74%, and the purity of gallium oxyhydroxide was 99.9974%.

[0085] Example 5

[0086] This example provides a method for efficiently and short-process preparing gallium oxyhydroxide, which specifically includes the following steps:

[0087] (1) Gallium nitrate was added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 4 mol / L;

[0088] (2) The high-gravity reactor was started, and its rotation speed was adjusted to 2500 r / min. The reaction was carried out at a temperature of 220 °C for 8 h, so that gallium nitrate and water directly reacted under a high-gravity field and were converted into gallium oxyhydroxide in one step;

[0089] (3) After the reaction, it was cooled to room temperature, and then the obtained slurry was subjected to solid-liquid separation. The obtained filter residue was washed 8 times with deionized water;

[0090] (4) The washed filter residue was dried at a temperature of 150 °C for 8 h to obtain gallium oxyhydroxide powder material.

[0091] Using the treatment method of this example, the obtained gallium oxyhydroxide powder was weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the conversion rate of gallium nitrate to gallium oxyhydroxide was 99.86%, and the purity of gallium oxyhydroxide was 99.9989%.

[0092] Comparative Example 1

[0093] This comparative example provides a method for preparing gallium oxyhydroxide in a high-pressure reaction kettle, which specifically includes the following steps:

[0094] (1) Gallium nitrate is added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 2 mol / L;

[0095] (2) The gallium nitrate solution is placed in a high-pressure reactor with a polytetrafluoroethylene liner and reacted at a temperature of 150 °C for 12 h to produce gallium oxyhydroxide through a reaction;

[0096] (3) After the reaction is completed, it is cooled to room temperature, and then the obtained slurry is subjected to solid-liquid separation. The obtained filter residue is washed 6 times with deionized water;

[0097] (4) The washed filter residue is dried at a temperature of 120 °C for 24 h to obtain a gallium oxyhydroxide powder material.

[0098] Using the treatment method of this example, the obtained gallium oxyhydroxide powder is weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 86.52%, and the purity of gallium oxyhydroxide is 99.982%.

[0099] Comparative Example 2

[0100] This comparative example provides a method for preparing gallium oxyhydroxide using a rotating packed bed reactor, which specifically includes the following steps:

[0101] (1) Gallium nitrate is added to deionized water and dissolved in deionized water to obtain a gallium nitrate solution with a concentration of 2 mol / L;

[0102] (2) The gallium nitrate solution is placed in a rotating packed bed reactor. The rotating packed bed reactor is started, and its rotation speed is adjusted to 1500 r / min. The reaction is carried out at a temperature of 100 °C for 12 h, so that gallium nitrate and water directly react under a high gravitational field to be converted into gallium oxyhydroxide in one step;

[0103] (3) After the reaction is completed, it is cooled to room temperature, and then the obtained slurry is subjected to solid-liquid separation. The obtained filter residue is washed 6 times with deionized water;

[0104] (4) The washed filter residue is dried at a temperature of 120 °C for 24 h to obtain a gallium oxyhydroxide powder material.

[0105] Using the treatment method of this example, the obtained gallium oxyhydroxide powder is weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 89.43%, and the purity of gallium oxyhydroxide is 99.980%.

[0106] Comparative Example 3

[0107] A method for preparing gallium oxyhydroxide using a rotating packed bed reactor in this comparative example specifically includes the following steps:

[0108] (1) Gallium nitrate is added to deionized water and dissolved in the deionized water to obtain a gallium nitrate solution with a concentration of 3 mol / L;

[0109] (2) The high-gravity reactor is started, and its rotation speed is adjusted to 600 r / min. The reaction is carried out for 10 h at a temperature of 180 °C, so that gallium nitrate and water directly react under a high-gravity field and are converted into gallium oxyhydroxide in one step;

[0110] (3) After the reaction is completed, it is cooled to room temperature, and then the obtained slurry is subjected to solid-liquid separation. The obtained filter residue is washed 6 times with deionized water;

[0111] (4) The washed filter residue is dried at a temperature of 140 °C for 10 h to obtain a gallium oxyhydroxide powder material.

[0112] By using the treatment method of this example, the obtained gallium oxyhydroxide powder is weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 92.74%, and the purity of gallium oxyhydroxide is 99.978%.

[0113] Comparative Example 4

[0114] A method for preparing gallium oxyhydroxide by using a high-gravity reactor in this comparative example specifically includes the following steps:

[0115] (1) Gallium nitrate is added to deionized water and dissolved in the deionized water to obtain a gallium nitrate solution with a concentration of 0.02 mol / L;

[0116] (2) The gallium nitrate solution is placed in a high-gravity reactor. The high-gravity reactor is started, and its rotation speed is adjusted to 1000 r / min. The reaction is carried out for 18 h at a temperature of 120 °C, so that gallium nitrate and water directly react under a high-gravity field and are converted into gallium oxyhydroxide in one step;

[0117] (3) After the reaction is completed, it is cooled to room temperature, and then the obtained slurry is subjected to solid-liquid separation. The obtained filter residue is washed 3 times with deionized water;

[0118] (4) The washed filter residue is dried at a temperature of 100 °C for 36 h to obtain a gallium oxyhydroxide powder material.

[0119] By using the treatment method of this example, the obtained gallium oxyhydroxide powder is weighed and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The result shows that the conversion rate of gallium nitrate to gallium oxyhydroxide is 93.63%, and the purity of gallium oxyhydroxide is 99.696%.

[0120] In addition, one or more technical solutions in the embodiments of the present application at least further have the following technical effects or advantages:

[0121] In the embodiment of the present application, gallium nitrate and water are used as raw materials, and under the action of a high-gravity reactor through a high-gravity field, gallium nitrate and water are rapidly and efficiently converted into gallium oxyhydroxide through a one-step reaction. The technical solution of the present invention has the advantages of short process flow, high reaction efficiency, and no consumption of chemical reagents such as acids and alkalis, and can realize the green, rapid, efficient, and low-cost preparation of gallium oxyhydroxide powder.

[0122] In the embodiment of the present application, under the action of a high-gravity field, the high dispersion, high turbulence, strong mixing, and rapid interface renewal of the gallium nitrate aqueous solution are achieved, so that the reaction between gallium ions and water molecules will be directly in an activated state, thereby promoting the increase of the reaction rate and realizing the rapid and efficient conversion of gallium oxyhydroxide; on the other hand, under the action of a high-gravity field, intense collisions occur between water molecules, and a large amount of heat is generated by strong friction, causing the temperature of the system to rise rapidly, and the heat intensity of the reaction is high. Compared with the traditional mechanical stirring reactor, under the action of a high-gravity field, more sufficient kinetic conditions can be provided, and the thermodynamic and kinetic synergistic strengthening of the reaction between gallium ions and water can be realized, which is beneficial to the efficient conversion of gallium oxyhydroxide.

[0123] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for preparing gallium oxyhydroxide by a short process, the method comprising: Dissolving gallium nitrate in deionized water to obtain a gallium nitrate solution with a set concentration; Placing the gallium nitrate solution under a high-gravity field to cause a conversion reaction between gallium nitrate and deionized water in the gallium nitrate solution, thereby obtaining a mixed solution containing gallium oxyhydroxide; Performing solid-liquid separation and drying on the mixed solution to obtain gallium oxyhydroxide powder.

2. The method according to claim 1, wherein The set concentration is 0.05 mol / L to 5 mol / L.

3. The method according to claim 1, wherein The device for generating the high-gravity field is a high-gravity reactor.

4. The method according to claim 3, characterized in that, The material of the high-gravity reactor is Hastelloy, titanium material or stainless steel.

5. The method according to claim 3, characterized in that, The rotation speed of the high-gravity reactor is 1000 r / min to 3000 r / min.

6. The method according to claim 1, wherein The reaction temperature of the conversion reaction is 120°C to 260°C, and the reaction time of the conversion reaction is 0.5 h to 20 h.

7. The method according to claim 1, wherein The filter residue obtained from the solid-liquid separation is washed 3 to 10 times with deionized water.

8. The method according to claim 1, wherein The drying temperature is 90°C to 160°C, and the drying time is 4 h to 48 h.

9. The method according to claim 1, wherein The conversion rate of gallium nitrate to gallium oxyhydroxide is ≥99.5%.

10. The method according to claim 1, characterized in that The purity of the gallium oxyhydroxide powder is ≥99.995%.

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