A quartz micro powder and its growth method

Abstract

This application provides a quartz micropowder and its growth method, wherein the size of the quartz micropowder is 180-400 micrometers. The quartz micropowder provided in this application has a size of 180-400 micrometers, which facilitates processing into various quartz devices. This effectively meets the size requirements of quartz micropowder for quartz device processing, not only enabling the reuse of quartz waste but also alleviating the problem of insufficient production of high-purity quartz materials.

Description

Technical Field

[0001] This application relates to the field of inorganic material processing and synthesis technology, and in particular to a quartz micropowder and its growth method. Background Technology

[0002] Currently, high-purity quartz sand is widely used in industries such as large-scale integrated circuits, solar cells, optical fibers, lasers, aerospace, and military.

[0003] However, since high-purity quartz mainly comes from minerals and its output is limited, and its production process involves processes such as mineral processing, crushing, screening, washing, grinding, and impurity removal, some quartz sand is over-ground to a size of less than 100 micrometers. Because the processing of quartz devices has strict requirements on the size of the quartz sand, this part of the quartz sand with a size of less than 100 micrometers is difficult to utilize, resulting in a large waste of resources. Summary of the Invention

[0004] The technical problem to be solved by this application is to provide a quartz micro powder and its growth method, so as to solve the technical problem that existing quartz sand waste cannot be effectively utilized due to its small size.

[0005] To solve the above problems, this application provides the following technical solution:

[0006] This application discloses a quartz micro powder, wherein the size of the quartz micro powder is 180-400 micrometers.

[0007] The quartz micro powder provided in this application has a size of 180-400 micrometers, which is convenient for processing and molding into various quartz devices. It can effectively meet the size requirements of quartz micro powder for quartz device processing, and can not only realize the reuse of quartz waste, but also alleviate the problem that the production of high-purity quartz materials cannot meet the demand.

[0008] Furthermore, the purity of the quartz micro powder is greater than or equal to 4N8.

[0009] This application also proposes a method for growing quartz micropowder, comprising:

[0010] A first quartz micropowder and silicon powder are reacted in an alkaline solution to generate a suspension comprising nano-silica and a second quartz micropowder; in the growth method, the first quartz micropowder and silicon powder are reacted in an alkaline solution, and the mass ratio of silicon powder to the first quartz micropowder is 1:5 to 10:1; in the growth method, the amount of alkaline solution added is 5 to 20 times the total mass of silicon powder;

[0011] The suspension was heated and dried to obtain a dried body;

[0012] The dried body is subjected to high-temperature annealing to obtain the grown quartz micro powder.

[0013] In this application, the reaction treatment of quartz micro powder and silicon powder is simple and convenient to operate and easy to promote industrialization. Large-sized quartz micro powder is prepared, which not only realizes the reuse of small-sized quartz micro powder, but also further alleviates the shortage of high-purity quartz materials.

[0014] Furthermore, before subjecting the dried body to high-temperature annealing, the method further includes:

[0015] The dried material is pulverized to the target size.

[0016] Furthermore, in the growth method, the alkaline solution includes an aqueous solution of at least one of ammonia, ethylenediamine, diethylamine, morpholine, propanolamine, monoethanolamine, diethanolamine, triethanolamine, N,N-dimethylhydroxyethylamine, N-methylhydroxyethylamine, and N-(β-aminomethyl)hydroxyethylamine.

[0017] Furthermore, in the growth method, the alkaline solution has a mass percentage of 0.5% to 20%.

[0018] Furthermore, in the growth method, the temperature at which the first quartz micro powder and silicon powder are reacted in an alkaline solution is 20℃~80℃, and the reaction time is 24~120h.

[0019] Furthermore, in the growth method, during the high-temperature annealing process of the dried body, the annealing temperature is 1100℃~1600℃ and the annealing time is 1~24h.

[0020] Furthermore, in the growth method, the first quartz micro powder includes at least one of the following: quartz micro powder produced by grinding during the production of natural quartz sand, quartz micro powder produced by grinding during the production of synthetic quartz sand, waste quartz glass, and quartz crucible recycling; and / or the raw materials of the silicon powder include at least one of the following: granular silicon, polycrystalline silicon waste, silicon waste from organosilicon production, silicon pot bottom material from crystal pulling, and wire-cut silicon powder.

[0021] Furthermore, in the growth method, heating and drying the suspension to obtain a dried body includes:

[0022] The suspension was placed in an evaporating dish and heated until completely dry to obtain the dried body.

[0023] Furthermore, in the growth method described above, the evaporation dish is made of polytetrafluoroethylene and / or high-purity quartz glass.

[0024] Furthermore, in the growth method, the drying temperature is 80℃~250℃.

[0025] Furthermore, in the growth method, the particle size of the first quartz micropowder is 1 to 150 micrometers, and the purity is greater than or equal to 4N8.

[0026] Compared with the prior art, the embodiments of this application have the following advantages:

[0027] (1) The size of the quartz micro powder provided in this application is 180 to 400 micrometers, which is convenient to process and form into various quartz devices. It can effectively meet the size requirements of quartz micro powder for quartz device processing. It can not only realize the reuse of quartz waste, but also alleviate the problem that the production of high-purity quartz materials cannot meet the demand.

[0028] (2) The method provided in this application reacts the first quartz micro powder with silicon powder. It is simple and convenient to operate and easy to promote industrialization. It can prepare large-sized quartz micro powder, which not only realizes the reuse of small-sized quartz micro powder, but also further alleviates the shortage of high-purity quartz materials.

[0029] (3) The raw materials used in this application are waste materials that need to be treated or landfilled. The comprehensive utilization of waste materials can not only realize the resource utilization of solid waste, but also improve the economic efficiency of enterprise production and save production costs.

[0030] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0031] Figure 1 This is a flowchart of a method for growing quartz micropowder provided in an embodiment of this application;

[0032] Figure 2 This is a scanning electron microscope image of the quartz microparticles obtained in Example 1;

[0033] Figure 3 This is a scanning electron microscope image of the quartz microparticles obtained in Example 2;

[0034] Figure 4 This is a scanning electron microscope image of the quartz microparticles obtained from Comparative Example 1. Detailed Implementation

[0035] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] The applicant of this application discovered that high-purity quartz mainly comes from minerals, with limited production. Its production process involves mineral processing, crushing, screening, washing, grinding, and impurity removal. During the grinding stage, some quartz sand is excessively crushed to a size of less than 100 micrometers. Since the processing of quartz devices has strict requirements on the size of the quartz sand, this portion of quartz sand with a size of less than 100 micrometers is difficult to utilize, resulting in a large waste of resources.

[0037] To address the aforementioned problems, this application provides a quartz micropowder with a size ranging from 180 to 400 micrometers. For example, the size can be 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, and 400 micrometers, or any combination thereof. In this application, excessively finely ground small-sized quartz micropowder is grown to 180-400 micrometers, facilitating its processing into various quartz devices. This effectively meets the size requirements of quartz micropowder for quartz device processing, enabling the reuse of quartz waste and alleviating the problem of insufficient production of high-purity quartz materials.

[0038] Furthermore, the purity of the aforementioned quartz micro powder is greater than or equal to 4N8, which meets the requirements for ultrapure quartz sand and can be applied in industries such as large-scale integrated circuits, solar cells, optical fibers, lasers, aerospace, and military.

[0039] It should be noted that the range values ​​of 180 to 400 mentioned above in the embodiments of this application all include endpoint values.

[0040] Please see Figure 1 This illustrates a method for growing quartz micropowder according to an embodiment of this application, wherein, as... Figure 1 As shown, steps 101 to 103 are included:

[0041] Step 101: The first quartz micro powder and silicon powder are placed in an alkaline solution to react and generate a suspension containing nano-silica and the second quartz micro powder; the first quartz micro powder and silicon powder are placed in an alkaline solution to react, wherein the mass ratio of silicon powder to the first quartz micro powder is 1:5 to 10:1, and the amount of alkaline solution added is 5 to 20 times the total mass of silicon powder;

[0042] Step 102: Heat and dry the suspension to obtain a dried body;

[0043] Step 103: Perform high-temperature annealing on the dried body to obtain the grown quartz micro powder.

[0044] In step 101 above, the first quartz micropowder is fine-particle quartz micropowder. The first quartz micropowder and silicon powder are added separately to an alkaline solution. The silicon powder reacts with water under the catalysis of the alkaline solution to generate nano-silica, thus forming a mixed suspension of nano-silica and quartz micropowder. In step 102 above, the suspension containing nano-silica and quartz micropowder is placed in an evaporating vessel such as an evaporating dish and dried by heating or other methods. This allows the nano-silica to encapsulate the quartz micropowder, resulting in composite particles of nano-silica-encapsulated quartz micropowder spread evenly at the bottom of the evaporating vessel, which is the aforementioned dried body.

[0045] In step 103 above, the dried body including nano-silica and quartz powder is annealed and melted at high temperature, so that the nano-silica melts and fuses with the quartz powder, ultimately achieving the growth of quartz powder.

[0046] In the preparation method provided in this application embodiment, firstly, the first quartz micro powder and silicon powder are reacted in an alkaline solution to generate a suspension including nano-silica and second quartz micro powder; then, the suspension is heated and dried to obtain a dried body, and then the dried body is subjected to high-temperature annealing treatment to obtain grown quartz micro powder. This realizes the use of nano-silica to encapsulate the second quartz micro powder, obtaining composite particles of nano-silica-encapsulated second quartz micro powder. Through annealing, the nano-silica melts and fuses with the second quartz micro powder, ultimately realizing the growth of quartz micro powder. This not only enables the reuse of quartz waste, but also alleviates the problem that the production of high-purity quartz materials cannot meet the demand.

[0047] Optionally, in one embodiment, the particle size of the first quartz micropowder can be 1 to 150 micrometers, and the purity is greater than or equal to 4N8. By using high-purity first quartz micropowder with a purity greater than or equal to 4N8 as raw material, it is ensured that the finally obtained grown quartz micropowder is a dense quartz micropowder with a size of 180 to 400 micrometers.

[0048] Optionally, in one embodiment, the first quartz micro powder includes at least one of the following: quartz micro powder produced by grinding during the production of natural quartz sand, quartz micro powder produced by grinding during the production of synthetic quartz sand, waste quartz glass, and quartz crucible recycling. The raw material for the first quartz micro powder is waste that needs to be treated or landfilled. This comprehensive utilization of waste not only realizes the resource recovery of solid waste but also facilitates improved economic efficiency and reduced production costs for enterprises.

[0049] Optionally, in one embodiment, the raw materials for the aforementioned silicon powder include at least one of granular silicon, polycrystalline silicon waste, organosilicon production silicon waste, silicon pulling pot bottom material, and wire-cut silicon powder. Since the raw materials for the silicon powder are waste materials that require treatment or landfill, the comprehensive utilization of these waste materials not only realizes the resource recovery of solid waste but also facilitates the improvement of the economic efficiency of enterprise production and saves production costs.

[0050] In this embodiment, nano-silica generated from silicon powder under alkaline solution catalysis is used to encapsulate quartz micropowder, and then the nano-silica is melted onto the surface of the quartz micropowder by sintering to achieve the growth of the quartz micropowder.

[0051] In step 101 above, the mass ratio of silicon powder to first quartz micro powder is 1:5 to 10:1, which can provide enough nano-silica to generate enough quartz micro powder to grow large enough, and can also ensure the utilization rate of quartz micro powder and reduce production costs.

[0052] Optionally, in one embodiment, the alkaline solution includes an aqueous solution of at least one of ammonia, ethylenediamine, diethylamine, morpholine, propanolamine, monoethanolamine, diethanolamine, triethanolamine, N,N-dimethylhydroxyethylamine, N-methylhydroxyethylamine, and N-(β-aminomethyl)hydroxyethylamine.

[0053] The alkaline solution comprises 0.5% to 20% by mass, which can effectively catalyze the reaction of silicon material into nano-silica. Optionally, the mass percentage of the alkaline solution can be 0.5%, 0.8%, 1%, 2%, 5%, 8%, 10%, 12%, 15%, 18%, 20%, or any combination thereof.

[0054] In step 101 above, the amount of alkaline solution added is 5 to 20 times the total mass of silicon powder. Since the alkaline solution can dissolve up to one-fifth of its own mass of silicon powder, the above ratio effectively ensures complete dissolution of silicon powder, avoids the presence of unreacted silicon powder in the product, and also effectively considers energy consumption during the drying process.

[0055] Optionally, in one embodiment, in step 101 above, the temperature at which the silicon powder reacts in the alkaline solution is 40°C to 80°C, and the reaction time is 24 to 120 hours. Heating effectively promotes the reaction of silicon powder with water under the catalysis of the alkaline solution to form a silica suspension. The above-mentioned reaction temperature and time ensure that the silicon powder is fully reacted into nano-silica, effectively balancing energy consumption and adhesion performance.

[0056] Optionally, in one embodiment, step 102 includes:

[0057] The suspension was placed in an evaporating dish and heated until completely dry to obtain the dried body.

[0058] In this embodiment, the evaporating dish can be made of polytetrafluoroethylene or high-purity quartz glass, which contains very few metal impurities, thus ensuring the purity of the sample obtained after drying.

[0059] Optionally, the drying temperature can be 80℃ to 250℃, for example, 80℃, 90℃, 100℃, 120℃, 150℃, 180℃, 200℃, 220℃, 250℃ or any two of the above ranges.

[0060] Optionally, in one embodiment, the growth method provided in this application further includes, before subjecting the dried body to high-temperature annealing:

[0061] The dried material is pulverized to the target size.

[0062] In this embodiment, under stress, the dried body containing nano-silica / quartz powder formed during the heating and drying process of the suspension including nano-silica and quartz powder is in block form with a size of 200 micrometers to 1 centimeter.

[0063] In this embodiment, a sand making machine, a sand mill, an autogenous mill, a ball mill, etc. are used to crush and sieve the above-mentioned dried body to obtain composite particles of nano-silica-coated quartz micropowder with a size of 200-450 micrometers. This facilitates the full contact between the nano-silica coated on the surface of the quartz micropowder and the quartz micropowder, and then the particles are fused together by high-temperature annealing to achieve the growth of the quartz micropowder.

[0064] Optionally, in step 103 above, the annealing is performed in air or under vacuum, at a temperature of 1100°C to 1600°C and for a time of 1 hour to 24 hours. This process melts the nano-silica coating on the surface of the quartz powder and fuses it with the quartz powder, ultimately achieving the growth of the quartz powder and obtaining quartz powder with a size of 180–400 micrometers. Because the nano-silica generated from the silica powder is in the form of nanoparticles with a low melting point, it melts above 1100°C to achieve further bonding, forming a hard, dense, high-purity quartz powder.

[0065] To make the inventive objectives, technical solutions, and beneficial effects of this invention clearer, the invention is further described below with reference to embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0066] Example 1

[0067] (1) Take 40g of polycrystalline silicon powder and 20g of natural quartz sieved through a 100-micron sieve, place them in a plastic round-bottom flask, add 400g of alkaline solution, heat to 60℃ and react for 48 hours to generate a suspension containing nano-silica and quartz powder; wherein, the alkaline solution is ammonia water with a mass fraction of 10%;

[0068] (2) Place the above suspension in a high-purity quartz petri dish and evaporate at 140°C until the solution is completely dry to obtain a dried body;

[0069] (3) Use a sand making machine to crush the agglomerated dried body to 200 micrometers to 450 micrometers;

[0070] (4) The crushed and dried body is placed in a muffle furnace and annealed at 1400°C for 3 hours in an air atmosphere to obtain the grown quartz micro powder.

[0071] Example 2

[0072] (1) Take 40g of granular silicon and 100g of synthetic quartz sieved through a 100-micron sieve, place them in a plastic round-bottom flask, add 800g of alkaline solution, heat to 80℃ and react for 120 hours to generate a suspension containing nano-silica and quartz powder; wherein, the alkaline solution is a 20% ethylenediamine solution.

[0073] (2) Place the above suspension in a polytetrafluoroethylene petri dish and evaporate at 250°C until the solution is completely dry to obtain a dried body;

[0074] (3) Use a ball mill to break the agglomerated dried body to 200-450 micrometers;

[0075] (4) The crushed and dried body is placed in a muffle furnace and annealed at 1600℃ for 1 hour in an air atmosphere to obtain the grown quartz micro powder.

[0076] Example 3

[0077] (1) Take 40g of granular silicon and 100g of synthetic quartz sieved through a 50-micron sieve, place them in a plastic round-bottom flask, add 200g of alkaline solution, heat to 60℃ and react for 48 hours to generate a suspension containing nano-silica and quartz powder; wherein, the alkaline solution is a 20% ethylenediamine solution.

[0078] (2) Place the above suspension in a polytetrafluoroethylene petri dish and evaporate at 80°C until the solution is completely dry to obtain a dried body;

[0079] (3) Use an autogenous mill to break the agglomerated dried material down to 200-450 micrometers;

[0080] (4) The crushed and dried body was placed in a vacuum muffle furnace and annealed at 1100℃ for 10h to obtain the grown quartz micro powder.

[0081] Example 4

[0082] The difference between Example 4 and Example 1 is that in step (1), the amount of silicon powder added is adjusted to 20g and the amount of synthetic quartz added is 100g.

[0083] Example 5

[0084] The difference between Example 5 and Example 1 is that in step (1), the amount of silicon powder added is adjusted to 40g and the amount of synthetic quartz added is 4g.

[0085] Example 6

[0086] The difference between Example 6 and Example 1 is that in step (1), the amount of silicon powder added is adjusted to 40g and the amount of synthetic quartz added is 40g.

[0087] Example 7

[0088] The difference between Example 7 and Example 1 is that in step (1), the amount of alkaline solution added is adjusted to 200g.

[0089] Example 8

[0090] The difference between Example 8 and Example 1 is that in step (1), the amount of alkaline solution added is adjusted to 800g.

[0091] Example 9

[0092] The difference between Example 9 and Example 1 is that in step (1), the amount of alkaline solution added is adjusted to 300g.

[0093] Example 10

[0094] The difference between Example 10 and Example 1 is that in step (1), the alkaline solution is adjusted to an ammonia solution with a mass fraction of 0.5%.

[0095] Example 11

[0096] The difference between Example 11 and Example 1 is that in step (1), the alkaline solution is adjusted to a 20% ethylenediamine solution.

[0097] Example 12

[0098] The difference between Example 12 and Example 1 is that in step (1), the reaction temperature is adjusted to 20°C and the time is 24h.

[0099] Example 13

[0100] The difference between Example 13 and Example 1 is that in step (1), the reaction temperature is adjusted to 80°C and the time is 120h.

[0101] Comparative Example 1

[0102] The difference between Comparative Example 1 and Example 1 is that in step (1), the amount of silicon particles added is adjusted to 0g.

[0103] Comparative Example 2

[0104] The difference between Comparative Example 2 and Example 1 is that in step (1), the amount of synthetic quartz sand added was adjusted to 2g.

[0105] Comparative Example 3

[0106] The difference between Comparative Example 3 and Example 1 is that in step (1), the amount of synthetic quartz sand added is adjusted to 300g.

[0107] Comparative Example 4

[0108] The difference between Comparative Example 4 and Example 1 is that in step (1), the amount of alkaline solution added was adjusted to 140g.

[0109] Comparative Example 5

[0110] The difference between Comparative Example 5 and Example 1 is that the amount of alkaline solution added in step (1) was adjusted to 1100g.

[0111] Sample performance testing:

[0112] The quartz micro powders prepared in the above examples and comparative examples were subjected to relative tap density tests using a tap density meter, particle size tests using a scanning electron microscope, and purity tests using ICP. The test results are shown in Table 1.

[0113] Table 1

[0114]

[0115]

[0116] The scanning electron microscope (SEM) images of the quartz microparticles in Examples 1, 2, and 1 are shown below. Figures 2-4 As shown.

[0117] By combining Table 1 Figures 2-4 Comparing the various embodiments, it can be seen that the ratio of silicon powder to quartz and the amount of alkaline solution added are key steps for the growth of quartz micropowder. If the amount of silicon powder and alkaline solution added is too low or too high, the quartz particles will have difficulty growing, with a particle size Dv50 ≤ 85 micrometers and a relative tap density not exceeding 72%.

[0118] In summary, in this embodiment, the first quartz micropowder and silicon powder are first reacted in an alkaline solution to generate a suspension containing nano-silica and the second quartz micropowder. The suspension is then heated and dried to form a dry body, which is then subjected to high-temperature annealing to obtain the grown quartz micropowder. This process achieves the encapsulation of the second quartz micropowder with nano-silica, resulting in composite particles of nano-silica-encapsulated second quartz micropowder. Annealing melts the nano-silica, fusing it with the second quartz micropowder, ultimately achieving the growth of quartz micropowder. This not only enables the reuse of quartz waste but also alleviates the problem of insufficient production of high-purity quartz materials.

[0119] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0120] The above provides a detailed description of a quartz micron powder and its growth method provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for growing quartz micropowder, characterized in that, include: The first quartz micro powder and silicon powder are reacted in an alkaline solution to generate a suspension containing nano-silica and the second quartz micro powder. The first quartz micro powder and silicon powder are placed in an alkaline solution for reaction, wherein the mass ratio of silicon powder to the first quartz micro powder is 1:5 to 10:1, and the amount of alkaline solution added is 5 to 20 times the total mass of silicon powder. The suspension was heated and dried to obtain a dried body; The dried body is subjected to high-temperature annealing to obtain grown quartz micro powder, the size of which is 180~400 micrometers. The alkaline solution includes an aqueous solution of at least one of ammonia, ethylenediamine, diethylamine, morpholine, propanolamine, monoethanolamine, diethanolamine, triethanolamine, N,N-dimethylhydroxyethylamine, N-methylhydroxyethylamine, and N-(β-aminomethyl)hydroxyethylamine.

2. The growth method according to claim 1, characterized in that, Before subjecting the dried body to high-temperature annealing, the method further includes: The dried material is pulverized to the target size.

3. The growth method according to claim 1, characterized in that, The alkaline solution has a mass percentage of 0.5% to 20%, and / or the temperature at which the first quartz micro powder and silicon powder are reacted in the alkaline solution is 20°C to 80°C, and the reaction time is 24 to 120 hours.

4. The growth method according to claim 1, characterized in that, During the high-temperature annealing process of the dried body, the annealing temperature is 1100℃~1600℃ and the annealing time is 1~24h.

5. The growth method according to claim 1, characterized in that, The first quartz micro powder includes at least one of the following: quartz micro powder produced by grinding during the production of natural quartz sand, quartz micro powder produced by grinding during the production of synthetic quartz sand, waste quartz glass, and quartz crucible recycling; and / or the raw materials of the silicon powder include at least one of the following: granular silicon, polycrystalline silicon waste, silicon waste from organosilicon production, silicon pulling pot bottom material, and wire-cut silicon powder; and / or the particle size of the first quartz micro powder is 1 to 150 micrometers, and the purity is greater than or equal to 4N8.

6. The growth method according to claim 1, characterized in that, The suspension is heated and dried to obtain a dried body, comprising: The suspension was placed in an evaporating dish and heated until completely dry to obtain the dried body.

7. The growth method according to claim 6, characterized in that, The evaporating dish is made of polytetrafluoroethylene and / or high-purity quartz glass; and / or the drying temperature is 80℃~250℃.

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