Method for preparing ultra-pure quartz by multi-stage synergistic purification of quartz ore

Abstract

The invention discloses a method for preparing ultra-high-purity quartz by multi-stage synergistic purification of quartz ore, and belongs to the technical field of ultra-high-purity quartz preparation. According to the method, natural quartz ore is used as a raw material, mineral impurities, lattice impurities and inclusions in quartz are deeply removed through multi-stage synergistic processes such as low-temperature plasma activation, biological leaching, supercritical CO2-assisted acid leaching, microwave-assisted chloridizing roasting and pulsed electric field enhanced acid leaching, and finally a high-purity quartz product with the SiO2 purity larger than or equal to 99.998% (4N8 grade) is obtained. According to the invention, a low-temperature plasma activation technology, microbial metallurgy, supercritical fluid extraction and a pulsed electric field strengthening technology are organically combined, so that the energy efficiency bottleneck and environmental protection limitation of a traditional high-purity quartz preparation process are broken through; the obtained quartz sand product can reach the standards of high-purity quartz sand for semiconductor quartz glass and high-purity quartz sand for photovoltaic quartz crucibles.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-high purity quartz preparation, and in particular to a method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore. Background Art

[0002] At present, the application field of quartz materials has gradually expanded from traditional basic industries such as glass manufacturing, construction and building materials, metallurgy and chemical industry to high-tech strategic emerging industries. High-purity quartz (SiO2 content>99.99%) has excellent optical properties (light transmittance>99.8%), excellent high temperature resistance (softening point up to 1730℃), excellent insulation properties (volume resistivity>10 16 cm) and excellent chemical stability, it has now become an indispensable key basic material in high-end manufacturing fields such as aerospace, semiconductor integrated circuits, photovoltaic new energy, precision optics and fiber optic communications.

[0003] In the photovoltaic energy sector, high-purity quartz is a core auxiliary material for the production of high-efficiency crystalline silicon solar cells. Its excellent thermal stability and chemical inertness ensure that solar cell modules maintain stable photoelectric conversion efficiency (>22%) and a service life of over 25 years under long-term outdoor conditions. In the semiconductor manufacturing industry, high-purity quartz is both a key carrier material for single-crystalline silicon growth and a primary raw material for quartz crucibles. Because transition metal impurities significantly reduce wafer yield and crucible life, semiconductor-grade high-purity quartz sand has extremely stringent purity requirements. The total amount of alkali metal and heavy metal impurities must be controlled below 15μg / g, and the content of certain key impurity elements (such as Al, Fe, and Ti) must not exceed 2μg / g. In the field of optical fiber communications, high-purity quartz optical fiber, with its ultra-low loss (<0.2dB / km@1550nm) and ultra-wide bandwidth, has become the fundamental transmission medium for 5G communication networks. To ensure signal transmission quality, the SiO2 purity of the quartz material used in optical fiber preforms must exceed 99.997%, and the hydroxyl content must be strictly controlled below 1ppm.

[0004] Currently, the industrial production process for high-purity quartz consists of two key steps: first, raw material pretreatment through physical methods such as crushing, screening, gravity separation, color sorting, roasting, and mechanical scrubbing; and second, deep impurity removal through chemical purification techniques such as high-gradient magnetic separation, flotation, acid leaching, hot alkali treatment, and atmosphere-controlled roasting. However, the traditional process has the following bottlenecks:

[0005] (1) High energy consumption and high cost: Traditional roasting (≥1000℃) and acid leaching processes consume a lot of energy and high consumption of reagents (such as HF and HCl), which is not in line with the trend of green manufacturing;

[0006] (2) Insufficient adaptability of flotation technology: Gangue minerals (such as feldspar and mica) from different sources vary greatly, requiring customized reagent systems. Process adjustments are complex, making stable production difficult.

[0007] (3) Lattice impurities are difficult to remove: Al 3+ 、Ti 4+ Impurities such as Si replace Si in an isomorphous form 4+ into the quartz lattice, causing charge imbalance and introducing compensating ions (such as Li + 、Na + , K + ), which is difficult to be effectively removed by existing physical and chemical methods;

[0008] (4) Gas-liquid inclusions affect purity: Primary inclusions (<10 μm) easily form bubbles when melting quartz glass at high temperatures, which reduces the optical properties of the product and is difficult to completely remove with existing technology.

[0009] Therefore, it is of great significance to improve and develop new high-purity quartz technology and prepare 4N8 grade high-purity quartz from quartz ore. Summary of the Invention

[0010] The main purpose of the present invention is to provide a method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore, so as to solve the technical problems existing in the prior art.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore comprises the following steps:

[0013] (1) Raw material pretreatment: crushing natural quartz ore and removing impurities to obtain primary quartz sand;

[0014] (2) Low-temperature plasma activation: In an inert gas atmosphere, the primary quartz sand is treated with radio frequency plasma for non-thermal plasma treatment to oxidize the impurity elements on the quartz surface and in the cracks and form active sites, thereby obtaining plasma-activated quartz sand;

[0015] (3) Bioleaching and impurity removal: The plasma-activated quartz sand is mixed with the composite bacterial solution and then shaken to selectively dissolve and leach metal oxide impurities to obtain quartz sand after bioleaching and impurity removal;

[0016] (4) Supercritical CO2-assisted acid leaching: The quartz sand after biological leaching is ground until the exposed area of ​​lattice impurities increases, and then the mixed solution is injected and supercritical reaction is carried out until the lattice impurities are removed to obtain supercritical treated quartz sand;

[0017] (5) Microwave-assisted chlorination roasting: quartz sand after supercritical treatment is mixed with ammonium chloride and then microwave roasted until the residual impurities are chlorinated and volatilized to obtain a roasted product;

[0018] (6) Directed water quenching and deep purification: The calcined product is quenched and then subjected to pulsed electric field-assisted hydrofluoric acid-oxalic acid mixed acid leaching to finally obtain high-purity quartz with SiO2 purity ≥99.998% (4N8 grade).

[0019] Furthermore, the natural quartz ore in step (1) is crushed to a particle size of 0.5 to 2 mm.

[0020] Furthermore, in step (2), the non-thermal plasma RF power is 10 to 1000 W, and the working pressure is 10 to 120 Pa; the inert gas is a mixture of argon and oxygen in a volume ratio of 8 to 9:1; the treatment time of the non-thermal plasma treatment is 10 to 30 minutes; the surface temperature of the quartz sand is controlled below 80°C during plasma treatment; and the impurity elements are Al, Fe, and Ti.

[0021] Furthermore, the solid-liquid ratio between the quartz sand and the composite bacterial solution in step (3) is 1: (5-10) g / mL; the composite bacterial solution is composed of acidulthiobacillus and oxalicum at a bacterial population ratio of 3-4:1; the composite bacterial solution OD 600 The value is 0.8~1.2.

[0022] Furthermore, the oscillation in step (3) is carried out by oscillating and leaching at a pH of 1.5 to 2.5 and a temperature of 25 to 35° C. for 1 to 3 days.

[0023] Furthermore, the grinding in step (4) is to wet-mill the quartz sand after bioleaching and impurity removal to 45-75 μm, the milling medium is zirconia beads, the milling speed is 200-300 rpm, and the milling time is 0.5-1 h.

[0024] Furthermore, the mixed solution in step (4) is 0.1-0.5 mol / L citric acid and 0.05-0.1 mol / L ammonium fluoride, and the volume ratio of the two is 1:(1-3); the solid-liquid ratio of the quartz sand after bioleaching and impurity removal to the mixed solution is 1:(3-5) g / mL; and the supercritical reaction is carried out in a supercritical CO2 reactor at a pressure of 8-15 MPa and a temperature of 50-80°C for 2-4 hours.

[0025] Furthermore, the mass ratio of the supercritical treated quartz sand to ammonium chloride in step (5) is 1:(0.05-0.1); and the microwave calcination is performed at 400-500° C. for 1-2 hours.

[0026] Furthermore, the quenching in step (6) is performed by putting the calcined product into ultrapure water containing 0.1% polyethylene glycol for quenching.

[0027] Furthermore, in step (6), the frequency of the pulsed electric field is 1 to 5 kHz, the intensity is 10 to 20 kV / cm, and the action time is 10 to 30 minutes; the volume ratio of hydrofluoric acid to oxalic acid is 1:(3 to 4), the concentration of hydrofluoric acid is 0.2 to 0.5 mol / L, and the concentration of oxalic acid is 0.5 to 1 mol / L; and the solid-liquid ratio of the calcined product to the hydrofluoric acid-oxalic acid mixed acid is 1:(4 to 6) g / mL.

[0028] The beneficial effects of the present invention are:

[0029] (1) This invention innovatively utilizes low-temperature plasma activation, microbial metallurgy, supercritical fluid extraction, and pulsed electric field enhancement to produce high-purity quartz, breaking through the energy efficiency bottlenecks and environmental limitations of traditional high-purity quartz production processes. The resulting quartz sand product meets the standards for high-purity quartz sand used in semiconductor quartz glass and photovoltaic quartz crucibles.

[0030] (2) The present invention removes impurities by introducing low-temperature plasma activation and bioleaching processes, significantly reducing energy consumption and pollution. This solves the problem that the preparation of high-purity quartz in the prior art mostly relies on high-temperature roasting or strong acid leaching, resulting in high energy consumption and pollution. By adopting the bioleaching process, waste acid emissions can be reduced by more than 60%.

[0031] (3) The present invention solves the problem of traditional process to remove lattice impurities (such as Al 3+ 、Ti 4+ ) to address the issue of incomplete removal. Furthermore, supercritical CO2 technology enables reagent recycling, surpassing traditional acid leaching filtrate reuse. The use of secondary grinding and supercritical fluid technology enhances the penetration and removal of lattice impurities by the citric acid-ammonium fluoride mixture. Pulsed electric field-assisted acid leaching can target impurity-quartz interfacial bonds, reducing HF usage.

[0032] (4) The microwave chlorination roasting of the present invention can achieve efficient chlorination and volatilization of impurities at 400-500°C, saving more than 30% energy compared with traditional roasting. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a process flow chart of the method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to the present invention.

[0034] Figure 2 These are SEM and EDS images of natural quartz ore and high-purity quartz (as can be seen from the figure, the impurity content in the high-purity quartz obtained after the natural quartz ore is treated with the technology of the present invention is significantly reduced). DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] Example 1

[0037] In this embodiment, natural quartz ore with a SiO2 content of 95% is used as raw material, and is gradually purified through the following experimental process to finally obtain a high-purity quartz product with a SiO2 content of not less than 99.998%.

[0038] Step S1: Raw material pretreatment: crushing natural quartz ore with a SiO2 content of 95% to a particle size of 0.5 mm, removing visible impurities through a color sorter, and obtaining primary quartz sand;

[0039] Step S2: Low-temperature plasma activation: In an inert gas atmosphere of a mixture of argon and oxygen in a volume ratio of 9:1, the primary quartz sand was subjected to non-thermal plasma treatment (non-thermal plasma RF power of 10 W, working pressure of 120 Pa, treatment temperature of 70°C, and time of 25 minutes) using a radio frequency plasma with a power of 1000 W and a working pressure of 120 Pa to oxidize the impurity elements (Al, Fe, Ti) on the quartz surface and in the cracks and form active sites;

[0040] Step S3: Bioleaching and impurity removal: The plasma-activated quartz sand was mixed with a composite bacterial solution of Acidithiobacillus ferrooxidans and Penicillium oxalicum at a solid-liquid ratio of 1:5 g / mL, and leached under oscillation at pH 2.5 and 25°C for 2 days to selectively dissolve metal oxide impurities; the bacterial population ratio of Acidithiobacillus ferrooxidans and Penicillium oxalicum in the composite bacterial solution was 3:1, and the OD of the composite bacterial solution was 0.1. 600 The value is 0.8.

[0041] Step S4: Supercritical CO2-assisted acid leaching: The quartz sand after bioleaching is wet-milled for a second time to 75 μm, wherein the ball milling medium is zirconia beads, the rotation speed is 300 rpm, and the ball milling time is 1 h to increase the exposed area of ​​lattice impurities; then, it is placed in a supercritical CO2 reactor, and a mixed solution containing 0.5 mol / L citric acid and 0.05 mol / L ammonium fluoride (the volume ratio of the two is 1:3) is injected, and the reaction is carried out at a pressure of 15 MPa and a temperature of 60°C for 2 hours to deeply remove lattice impurities; wherein, the solid-liquid ratio of quartz sand to the mixed solution is 1:4 g / mL.

[0042] Step S5: Microwave-assisted chlorination roasting: quartz sand after supercritical treatment was mixed with ammonium chloride in a mass ratio of 1:0.05, and roasted at 500° C. for 1.5 hours in a microwave reactor with a frequency of 2.45 GHz and a power of 3 kW to volatilize the residual impurities by chlorination;

[0043] Step S6: Directed Water Quenching and Deep Purification: The calcined product is rapidly quenched in ultrapure water containing 0.1% polyethylene glycol. It is then leached for 15 minutes in a hydrofluoric acid-oxalic acid mixed acid leaching process assisted by a pulsed electric field at a frequency of 1-5 kHz and an intensity of 15 kV / cm, ultimately yielding a high-purity quartz product with a SiO2 purity of 99.998%. The hydrofluoric acid-oxalic acid mixed acid leaching process uses a volume ratio of 1:3, with a hydrofluoric acid concentration of 0.3 mol / L and an oxalic acid concentration of 0.8 mol / L. The solid-liquid ratio of quartz sand to the mixed acid is 1:5 g / mL.

[0044] Example 2

[0045] In this embodiment, natural quartz ore with a SiO2 content of 95% is used as raw material, and is gradually purified through the following experimental process to finally obtain a high-purity quartz product with a SiO2 content of not less than 99.998%.

[0046] Step S1: Raw material pretreatment: crush natural quartz ore with a SiO2 content of 95% to a particle size of 2 mm, remove visible impurities through a color sorter, and obtain primary quartz sand;

[0047] Step S2: Low-temperature plasma activation: In an inert gas atmosphere of a mixture of argon and oxygen in a volume ratio of 8:1, the primary quartz sand is subjected to non-thermal plasma treatment (non-thermal plasma RF power of 1000 W, working pressure of 10 Pa, treatment temperature of 80°C, and time of 30 minutes) using a radio frequency plasma with a power of 10 W and an operating pressure of 10 Pa, to oxidize the impurity elements (Al, Fe, Ti) on the quartz surface and in the cracks and form active sites;

[0048] Step S3: Bioleaching and impurity removal: The plasma-activated quartz sand was mixed with a composite bacterial solution of Acidithiobacillus ferrooxidans and Penicillium oxalicum at a solid-liquid ratio of 1:6 g / mL, and leached under oscillation at pH 1.5 and 35°C for 1 day to selectively dissolve metal oxide impurities; the bacterial population ratio of Acidithiobacillus ferrooxidans and Penicillium oxalicum in the composite bacterial solution was 4:1, and the OD of the composite bacterial solution was 0.1. 600 The value is 1.2.

[0049] Step S4: Supercritical CO2-assisted acid leaching: The quartz sand after bioleaching is wet-milled for a second time to 45 μm, wherein the ball milling medium is zirconia beads, the rotation speed is 200 rpm, and the ball milling time is 0.8 h to increase the exposed area of ​​lattice impurities; then, it is placed in a supercritical CO2 reactor, and a mixed solution containing 0.1 mol / L citric acid and 0.1 mol / L ammonium fluoride (the volume ratio of the two is 1:1) is injected, and the reaction is carried out at a pressure of 8 MPa and a temperature of 80°C for 3 hours to deeply remove lattice impurities; wherein, the solid-liquid ratio of quartz sand to the mixed solution is 1:3 g / mL.

[0050] Step S5: Microwave-assisted chlorination roasting: quartz sand after supercritical treatment was mixed with ammonium chloride in a mass ratio of 1:0.1, and roasted at 400° C. for 1 hour in a microwave reactor with a frequency of 2.45 GHz and a power of 4 kW to volatilize the residual impurities by chlorination;

[0051] Step S6: Directed Water Quenching and Deep Purification: The calcined product is rapidly quenched in ultrapure water containing 0.1% polyethylene glycol. It is then leached for 10 minutes in a hydrofluoric acid-oxalic acid mixed acid leaching process assisted by a pulsed electric field at a frequency of 1-5 kHz and an intensity of 20 kV / cm, ultimately yielding a high-purity quartz product with a SiO2 purity of 99.998%. The hydrofluoric acid-oxalic acid mixed acid leaching process uses a volume ratio of 1:4, with a hydrofluoric acid concentration of 0.2 mol / L and an oxalic acid concentration of 0.5 mol / L. The solid-liquid ratio of quartz sand to mixed acid is 1:4 g / mL.

[0052] Example 3

[0053] In this embodiment, natural quartz ore with a SiO2 content of 95% is used as raw material, and is gradually purified through the following experimental process to finally obtain a high-purity quartz product with a SiO2 content of not less than 99.998%.

[0054] Step S1: Raw material pretreatment: crush natural quartz ore with a SiO2 content of 95% to a particle size of 1 mm, remove visible impurities through a color sorter, and obtain primary quartz sand;

[0055] Step S2: Low-temperature plasma activation: In an inert gas atmosphere of a mixture of argon and oxygen in a volume ratio of 9:1, the primary quartz sand was subjected to non-thermal plasma treatment (non-thermal plasma RF power 400 W, working pressure 80 Pa, treatment temperature 60°C, time 10 minutes) using a radio frequency plasma with a power of 500 W and an operating pressure of 60 Pa to oxidize the impurity elements (Al, Fe, Ti) on the quartz surface and in the cracks and form active sites;

[0056] Step S3: Bioleaching and impurity removal: The plasma-activated quartz sand was mixed with a composite bacterial solution of Acidithiobacillus ferrooxidans and Penicillium oxalicum at a solid-liquid ratio of 1:10 g / mL, and leached under oscillation at pH 2.0 and 30°C for 3 days to selectively dissolve metal oxide impurities; the bacterial population ratio of Acidithiobacillus ferrooxidans and Penicillium oxalicum in the composite bacterial solution was 3:1, and the OD of the composite bacterial solution was 0.1. 600 The value is 1.0.

[0057] Step S4: Supercritical CO2-assisted acid leaching: The quartz sand after bioleaching is wet-milled for a second time to 60 μm, wherein the ball milling medium is zirconia beads, the rotation speed is 300 rpm, and the ball milling time is 0.5 h to increase the exposed area of ​​lattice impurities; then, it is placed in a supercritical CO2 reactor, and a mixed solution containing 0.3 mol / L citric acid and 0.08 mol / L ammonium fluoride (the volume ratio of the two is 1:2) is injected, and the reaction is carried out at a pressure of 10 MPa and a temperature of 50°C for 5 hours to deeply remove lattice impurities; wherein, the solid-liquid ratio of quartz sand to the mixed solution is 1:5 g / mL.

[0058] Step S5: Microwave-assisted chlorination roasting: quartz sand after supercritical treatment was mixed with ammonium chloride in a mass ratio of 1:0.08, and roasted at 450° C. for 2 hours in a microwave reactor with a frequency of 2.45 GHz and a power of 5 kW to volatilize the residual impurities by chlorination;

[0059] Step S6: Directed Water Quenching and Deep Purification: The calcined product is rapidly quenched in ultrapure water containing 0.1% polyethylene glycol. It is then subjected to a hydrofluoric acid-oxalic acid mixed acid leaching for 30 minutes, assisted by a pulsed electric field at a frequency of 1-5 kHz and an intensity of 10 kV / cm, ultimately yielding a high-purity quartz product with a SiO2 purity of 99.998%. The hydrofluoric acid-oxalic acid mixed acid leaching method uses a volume ratio of 1:3, a hydrofluoric acid concentration of 0.5 mol / L, and an oxalic acid concentration of 1 mol / L. The solid-liquid ratio of quartz sand to mixed acid is 1:6 g / mL.

[0060] The above detailed description of the specific embodiments of the invention is intended to be illustrative only, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions to the invention are also within the scope of the present invention. Therefore, equivalent changes, modifications, and improvements made without departing from the spirit and scope of the present invention are also encompassed within the scope of the present invention.

Claims

1. A method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore, characterized in that: The steps include: (1) Crushing natural quartz ore and removing impurities to obtain primary quartz sand; (2) In an inert gas atmosphere, the primary quartz sand is subjected to non-thermal plasma treatment using radio frequency plasma to oxidize the impurity elements on the quartz surface and in the cracks and form active sites, thereby obtaining plasma-activated quartz sand; (3) The plasma-activated quartz sand is mixed with the composite bacterial solution and then oscillated to selectively dissolve and leach metal oxide impurities, thereby obtaining quartz sand after bioleaching and impurity removal; (4) Grinding the quartz sand after bioleaching and impurity removal until the exposed area of ​​the lattice impurities increases, then injecting the mixed solution and performing a supercritical reaction until the lattice impurities are removed to obtain supercritically treated quartz sand; (5) mixing the supercritical treated quartz sand with ammonium chloride and then calcining it with a microwave until the residual impurities are chlorinated and volatilized to obtain a calcined product; (6) The calcined product is quenched and then subjected to pulsed electric field-assisted hydrofluoric acid-oxalic acid mixed acid leaching to obtain high-purity quartz with SiO2 purity ≥99.998%.

2. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The natural quartz ore in step (1) is crushed to a particle size of 0.5-2 mm.

3. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: In step (2), the non-thermal plasma radio frequency power is 10-1000W, and the working pressure is 10-120Pa; the inert gas is a mixture of argon and oxygen with a volume ratio of 8-9:1; the treatment time of the non-thermal plasma treatment is 10-30 minutes; the surface temperature of the quartz sand is controlled below 80°C during the plasma treatment; and the impurity elements are Al, Fe, and Ti.

4. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The solid-liquid ratio between the quartz sand and the composite bacterial solution in step (3) is 1: (5-10) g / mL; the composite bacterial solution is composed of acidulthiobacillus and oxalicum at a bacterial population ratio of 3-4:1; the OD of the composite bacterial solution is 600 The value is 0.8~1.

2.

5. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 4, characterized in that: The oscillation in step (3) is carried out at a pH of 1.5 to 2.5 and a temperature of 25 to 35° C. for 1 to 3 days.

6. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The grinding in step (4) is to wet-mill the quartz sand after bioleaching and impurity removal to 45-75 μm, the milling medium is zirconia beads, the milling speed is 200-300 rpm, and the milling time is 0.5-1 h.

7. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The mixed solution in step (4) is 0.1-0.5 mol / L citric acid and 0.05-0.1 mol / L ammonium fluoride, and the volume ratio of the two is 1:(1-3); the solid-liquid ratio of the quartz sand after bioleaching and impurity removal to the mixed solution is 1:(3-5) g / mL; the supercritical reaction is carried out in a supercritical CO2 reactor at a pressure of 8-15 MPa and a temperature of 50-80°C for 2-4 hours.

8. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The mass ratio of the supercritical treated quartz sand to ammonium chloride in step (5) is 1:(0.05-0.1); and the microwave roasting is performed at 400-500° C. for 1-2 hours.

9. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: The quenching in step (6) is performed by placing the calcined product into ultrapure water containing 0.1% polyethylene glycol for quenching.

10. The method for preparing ultra-high purity quartz by multi-stage coordinated purification of quartz ore according to claim 1, characterized in that: In step (6), the frequency of the pulsed electric field is 1-5 kHz, the intensity is 10-20 kV / cm, and the action time is 10-30 minutes; the volume ratio of hydrofluoric acid to oxalic acid is 1:(3-4), the concentration of hydrofluoric acid is 0.2-0.5 mol / L, and the concentration of oxalic acid is 0.5-1 mol / L; the solid-liquid ratio of the calcined product to the hydrofluoric acid-oxalic acid mixed acid is 1:(4-6) g / mL.

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