Method for mechanically-chemically activated assisted sulfation roasting purification of quartz

Abstract

This invention relates to a method for purifying quartz through mechanochemical activation-assisted sulfation roasting, belonging to the field of high-purity quartz purification technology. The invention involves uniformly mixing coarse quartz particles with a solid reducing agent, and dry ball milling at an inert atmosphere and temperature of 400-900℃ for 2-10 hours to induce cracks in the coarse quartz particles, exposing internal impurities. Simultaneously, the solid reducing agent reduces and activates the impurities in the coarse quartz particles, and the mixture is sieved to obtain activated quartz powder. A sulfur oxide-containing gas is then introduced into the activated quartz powder, or the activated quartz powder is uniformly mixed with a solid sulfation reagent, and sulfation roasting is performed for 1-5 hours to deeply sulfate and transform the impurities in the activated quartz powder, yielding sulfated roasted quartz. The sulfated roasted quartz is then acid-leached, followed by solid-liquid separation. The solid is washed with deionized water and dried to obtain purified quartz. This invention achieves a dual synergistic effect of mechanical and chemical activation through ball milling, allowing impurities to be reduced and activated during the ball milling stage. The activated impurities are more conducive to the sulfation reaction.

Description

Technical Field

[0001] This invention relates to a method for purifying quartz by mechanochemical activation-assisted sulfation roasting, belonging to the field of high-purity quartz purification technology. Background Technology

[0002] Natural quartz ore often contains metallic impurities such as Al, K, Fe, and Ti, which severely restrict the purification effect of quartz.

[0003] Currently, the chemical purification of quartz mainly employs acid leaching, chlorination roasting, or a combination of both. Acid leaching utilizes mixed acids such as hydrofluoric acid, hydrochloric acid, and sulfuric acid to dissolve most free or fractured impurity minerals, but it struggles to effectively disrupt the stable structure of silicate minerals like muscovite. Chlorination roasting effectively removes impurities by converting them into low-boiling-point chlorides, but it requires sophisticated equipment and is expensive. Therefore, developing a short-process, high-efficiency purification method that can effectively destroy silicate impurities, activate internal impurities in quartz, and simultaneously simplify the process and reduce costs is of great significance for the preparation of high-purity quartz. Summary of the Invention

[0004] To address the challenges of removing silicate minerals and the complexity of the impurity removal process, this invention proposes a method for purifying quartz using a mechanical chemical activation-assisted sulfation roasting process. This method achieves a synergistic effect of mechanically breaking down quartz particles and chemically reducing impurities through temperature-controlled mixing and reduction ball milling. This allows silicate impurities in the quartz to be decomposed in advance, and high-valence oxides to be reduced to low-valence oxides. The activated impurities are then efficiently converted into sulfates through sulfation roasting. After acid leaching, the impurities in the quartz are effectively removed.

[0005] A method for purifying quartz by mechanochemical activation-assisted sulfation roasting includes the following steps: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) Mix coarse quartz particles with solid reducing agent evenly, place them in a high-temperature and high-energy ball mill, and dry ball mill them for 2 to 10 hours under an inert atmosphere and at a temperature of 400 to 900°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Place activated quartz powder in a rotary furnace and introduce sulfur oxide gas, or mix activated quartz powder with solid sulfation reagent evenly and place it in a rotary furnace for sulfation roasting for 1-5 hours to allow the impurities in the activated quartz powder to undergo deep sulfation conversion to obtain sulfated roasted quartz. (5) Sulfated roasted quartz is added to acid solution for acid leaching treatment, solid-liquid separation, and the solid is washed with deionized water and dried to obtain purified quartz.

[0006] Preferably, the solid reducing agent in step (2) is one or more of activated carbon, charcoal, and graphite, and the fixed carbon content in the solid reducing agent is not less than 85%.

[0007] Preferably, in step (2), the particle size of the solid reducing agent is ≤1mm, and the amount of solid reducing agent added is 0.5~10% of the mass of the coarse quartz particles.

[0008] Preferably, the grinding media in the dry ball milling step (2) is agate, zirconium oxide or corundum ceramic, the ball-to-material mass ratio is 10~20:1, and the ball milling speed is 300~800 rpm.

[0009] Preferably, in step (4), the sulfur oxide gas is SO3 gas or SO2-O2 mixed gas, the volume ratio of SO2 to O2 in the SO2-O2 mixed gas is 0.2~4:1, the introduction rate of the sulfur oxide gas is 200~800 mL / min, and the sulfation roasting temperature is 300~700℃.

[0010] Preferably, the solid sulfation reagent in step (4) is ammonium sulfate or ammonium bisulfate, the amount of solid sulfation reagent added is 10-30% of the mass of activated quartz powder, and the sulfation roasting temperature is 300-400℃.

[0011] Preferably, the rotational speed of the rotary furnace in step (4) is 5~20 rpm.

[0012] Preferably, the acid solution in step (5) is one or more of hydrochloric acid, sulfuric acid, and nitric acid, and the total concentration of the acid solution is 1~5 mol / L.

[0013] More preferably, in step (5), the liquid-to-solid ratio of acid solution to sulfated roasted quartz is 4~10:1 mL:g, the acid leaching temperature is 50~100℃, the stirring rate is 5~15 rpm, and the time is 1~5 h.

[0014] The beneficial effects of this invention are: (1) The ball milling stage of this invention achieves deep synergy between mechanical activation and chemical activation. The ball milling is carried out at a controlled temperature of 400~900℃. The mechanical force not only causes a large number of cracks in the quartz particles, thus exposing the internal impurities, but also the reducing agent destroys the silicate impurity structure at high temperature and reduces the high-valence oxides to a low-valence state, so that the impurities are in a highly active and easily sulfated state where the mineral structure is destroyed and the high-valence oxides are reduced, which significantly improves the efficiency of subsequent sulfation roasting. (2) The present invention combines ball milling reduction activation with sulfation roasting, eliminating the separate reduction roasting step, simplifying the process flow, and reducing equipment investment and operating costs. Attached Figure Description

[0015] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0017] In the embodiments of the present invention, the contents of Al, K, Fe and Ti in the raw quartz ore are 1582.88 ppmw, 547.67 ppmw, 421.83 ppmw and 90.12 ppmw, respectively; the fixed carbon contents of the solid reducing agent are 92 wt% activated carbon, 86 wt% charcoal and 98 wt% graphite.

[0018] Example 1: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) The coarse quartz particles are mixed evenly with a solid reducing agent (0.5% activated carbon by mass of coarse quartz particles), and placed in a high-temperature and high-energy ball mill. Agate balls are used as the ball milling medium. The coarse quartz particles are dry-milled for 2 hours under an inert atmosphere (argon) and a temperature of 400°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The ball-to-material mass ratio in the dry ball milling is 10:1, and the ball milling speed is 300 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Mix the activated quartz powder with a solid sulfation reagent (ammonium sulfate at 10% of the mass of the activated quartz powder) evenly and place it in a rotary furnace. Sulphate and roast the activated quartz powder for 1 hour at a rotation speed of 5 rpm and a temperature of 300℃ to achieve deep sulfation and transformation of impurities in the activated quartz powder to obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to acid solution (hydrochloric acid with a concentration of 1 mol / L) and acid leaching was performed at a temperature of 50℃ and a stirring rate of 5 rpm for 1 h. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (hydrochloric acid) to the sulfated roasted quartz was 4:1 mL:g. According to the test results, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment were 376.73 ppmw, 150.61 ppmw, 32.06 ppmw and 30.82 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 76.2%, 72.5%, 92.4% and 65.8%, respectively.

[0019] Example 2: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) Mix coarse quartz particles with a solid reducing agent (5% of the mass of coarse quartz particles in charcoal), place the mixture in a high-temperature, high-energy ball mill, use zirconia balls as the milling medium, and dry-mill for 5 hours in an inert atmosphere (nitrogen) at 700°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The mass ratio of balls to materials in the dry ball mill is 15:1, and the milling speed is 500 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Place the activated quartz powder in a rotary furnace and introduce sulfur oxide gas (SO3 gas with an introduction rate of 400 mL / min). Perform sulfation roasting for 3 hours at a rotation speed of 12 rpm and a temperature of 550℃ to deeply sulfate and transform the impurities in the activated quartz powder to obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to an acid solution (a mixed acid of hydrochloric acid and sulfuric acid, with a hydrochloric acid concentration of 1 mol / L and a sulfuric acid concentration of 2 mol / L) and subjected to acid leaching treatment at a temperature of 75℃ and a stirring rate of 10 rpm for 3 hours. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (the mixed acid of hydrochloric acid and sulfuric acid) to the sulfated roasted quartz was 7:1 mL:g. According to the test, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment are 242.18 ppmw, 104.06 ppmw, 20.25 ppmw and 24.78 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities are 84.7%, 81.0%, 95.2% and 72.5%, respectively.

[0020] Comparative Example 1: The difference between this comparative example and Example 2 is that it does not contain step (2). The coarse quartz particles from step (1) are directly further crushed and sieved to obtain quartz powder of 45~180 mesh. The quartz powder is placed in a rotary furnace and sulfur oxide gas (SO3 gas with a flow rate of 400 mL / min) is introduced. Then, the method of steps (4) and (5) in Example 2 is followed. The contents of Al, K, Fe and Ti impurities in the purified quartz of this comparative example were found to be 579.33 ppmw, 248.09 ppmw, 72.13 ppmw and 37.76 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 63.4%, 54.7%, 82.9% and 58.1%, respectively.

[0021] Comparative Example 2: The difference between this comparative example and Example 2 is that no solid reducing agent is added in step (2), and the coarse quartz particles from step (1) are directly activated by ball milling, and then carried out according to the methods of steps (3), (4) and (5) in Example 2; The contents of Al, K, Fe and Ti impurities in the purified quartz of this comparative example were found to be 462.20 ppmw, 185.11 ppmw, 48.51 ppmw and 31.18 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 70.8%, 66.2%, 88.5% and 65.4%, respectively.

[0022] Comparative Example 3: The difference between this comparative example and Example 2 is that it does not contain step (4), and the activated quartz powder obtained in step (3) is directly processed according to the method of step (5) in Example 2; The contents of Al, K, Fe and Ti impurities in the purified quartz of this comparative example were found to be 671.14 ppmw, 261.24 ppmw, 90.27 ppmw and 44.88 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 57.6%, 52.3%, 78.6% and 50.2%, respectively.

[0023] Example 3: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) The coarse quartz particles are mixed evenly with a solid reducing agent (graphite of 10% of the mass of the coarse quartz particles), and placed in a high-temperature and high-energy ball mill. Corundum balls are used as the ball milling medium. The coarse quartz particles are dry-milled for 10 hours in an inert atmosphere (argon) at a temperature of 900°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The mass ratio of ball to material in the dry ball milling is 20:1, and the ball milling speed is 800 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) The activated quartz powder was placed in a rotary furnace and a sulfur oxide gas was introduced (a SO2-O2 mixed gas with a total rate of 800 mL / min was introduced, and the volume ratio of SO2 to O2 in the SO2-O2 mixed gas was 2:1). The sulfation roasting was carried out for 5 hours at a rotation speed of 20 rpm and a temperature of 700℃ to deeply sulfate the impurities in the activated quartz powder and obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to an acid solution (a mixed acid of hydrochloric acid and nitric acid, with a hydrochloric acid concentration of 3 mol / L and a nitric acid concentration of 2 mol / L) and subjected to acid leaching treatment at 100℃ and a stirring rate of 15 rpm for 5 h. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (a mixed acid of hydrochloric acid and nitric acid) to the sulfated roasted quartz was 10:1 mL:g. According to the test, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment are 134.54 ppmw, 60.79 ppmw, 8.01 ppmw and 18.38 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities are 91.5%, 88.9%, 98.1% and 79.6%, respectively.

[0024] Example 4: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) The coarse quartz particles are mixed with a solid reducing agent (a mixture of activated carbon and graphite, with a mass ratio of 8% of the coarse quartz particles to 1:1), and placed in a high-temperature, high-energy ball mill. Corundum balls are used as the ball milling medium. The coarse quartz particles are dry-milled for 6 hours in an inert atmosphere (argon) at a temperature of 800°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The mass ratio of the ball to the material in the dry ball mill is 18:1, and the ball milling speed is 600 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Mix the activated quartz powder with a solid sulfation reagent (ammonium bisulfate of 30% of the activated quartz powder mass) evenly and place it in a rotary furnace. Sulphate and roast the activated quartz powder for 4 hours at a rotation speed of 15 rpm and a temperature of 400℃ to deeply sulfate and transform the impurities in the activated quartz powder to obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to an acid solution (a mixed acid of hydrochloric acid and sulfuric acid, with a hydrochloric acid concentration of 3 mol / L and a sulfuric acid concentration of 2 mol / L) and subjected to acid leaching treatment at 80°C and a stirring rate of 12 rpm for 4 hours. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (a mixed acid of hydrochloric acid and sulfuric acid) to the sulfated roasted quartz was 8:1 mL:g. According to the test results, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment were 185.20 ppmw, 81.06 ppmw, 13.50 ppmw and 21.36 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 88.3%, 85.2%, 96.8% and 76.3%, respectively.

[0025] Example 5: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) The coarse quartz particles are mixed evenly with a solid reducing agent (2% of the mass of the coarse quartz particles in charcoal), and placed in a high-temperature, high-energy ball mill. Zirconia balls are used as the ball milling medium. The coarse quartz particles are dry-milled for 4 hours in an inert atmosphere (nitrogen) at a temperature of 500°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The mass ratio of ball to material in the dry ball milling is 12:1, and the ball milling speed is 400 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Mix the activated quartz powder with a solid sulfation reagent (ammonium sulfate at 20% of the mass of the activated quartz powder) evenly and place it in a rotary furnace. Sulphate and roast the activated quartz powder for 2 hours at a speed of 10 rpm and a temperature of 350°C to deeply sulfate and transform the impurities in the activated quartz powder to obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to acid solution (hydrochloric acid with a concentration of 3 mol / L) and acid leaching was carried out at a temperature of 70℃ and a stirring speed of 8 rpm for 2 hours. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (hydrochloric acid) to the sulfated roasted quartz was 5:1 mL:g. According to the test, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment are 308.66 ppmw, 123.77 ppmw, 25.73 ppmw and 28.03 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities are 80.5%, 77.4%, 93.9% and 68.9%, respectively.

[0026] Example 6: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) The coarse quartz particles are mixed evenly with a solid reducing agent (6% activated carbon by mass of coarse quartz particles), and placed in a high-temperature, high-energy ball mill. Corundum balls are used as the ball milling medium. The coarse quartz particles are dry-milled for 7 hours under an inert atmosphere (argon) and a temperature of 600°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. The ball-to-material mass ratio in the dry ball milling is 16:1, and the ball milling speed is 550 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) The activated quartz powder was placed in a rotary furnace and a sulfur oxide gas was introduced (a SO2-O2 mixed gas with a total rate of 200 mL / min was introduced, and the volume ratio of SO2 to O2 in the SO2-O2 mixed gas was 4:1). The sulfation roasting was carried out at a rotation speed of 8 rpm and a temperature of 400℃ for 4 hours to allow the impurities in the activated quartz powder to undergo deep sulfation conversion to obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to acid solution (sulfuric acid with a concentration of 2 mol / L) and acid leaching was performed at a temperature of 60℃ and a stirring rate of 10 rpm for 3 hours. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (sulfuric acid) to the sulfated roasted quartz was 6:1 mL:g. According to the test, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment were 267.51 ppmw, 110.63 ppmw, 22.78 ppmw and 26.41 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 83.1%, 79.8%, 94.6% and 70.7%, respectively.

[0027] Example 7: A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, the specific steps of which are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) Quartz coarse particles are mixed with a solid reducing agent (a mixture of charcoal, activated carbon and graphite, with a mass ratio of 4% of the quartz coarse particles to 1:1:1), and placed in a high-temperature, high-energy ball mill. Agate balls are used as the ball milling medium. The mixture is dry-milled for 8 hours in an inert atmosphere (argon) at a temperature of 650°C to cause cracks in the quartz coarse particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the quartz coarse particles to obtain ball-milled activated quartz coarse particles. The mass ratio of ball to material in the dry ball milling is 14:1, and the ball milling speed is 450 rpm. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) The activated quartz powder was placed in a rotary furnace and a sulfur oxide gas was introduced (a SO2-O2 mixed gas with a total rate of 500 mL / min was introduced, and the volume ratio of SO2 to O2 in the SO2-O2 mixed gas was 0.2:1). The sulfation roasting was carried out for 3 hours at a rotation speed of 13 rpm and a temperature of 500℃ to deeply sulfate the impurities in the activated quartz powder and obtain sulfated roasted quartz. (5) Sulfated roasted quartz was added to acid solution (hydrochloric acid with a concentration of 4 mol / L) and acid leaching was carried out at a temperature of 90℃ and a stirring speed of 10 rpm for 4 hours. Solid-liquid separation was performed, and the solid was washed with deionized water and dried to obtain purified quartz. The liquid-solid ratio of the acid solution (hydrochloric acid) to the sulfated roasted quartz was 9:1 mL:g. According to the test results, the contents of Al, K, Fe and Ti impurities in the purified quartz in this embodiment were 294.42 ppmw, 116.77 ppmw, 29.95 ppmw and 25.68 ppmw, respectively, and the removal rates of Al, K, Fe and Ti impurities were 81.4%, 78.68%, 92.9% and 71.5%, respectively.

[0028] The specific embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for purifying quartz by mechanochemical activation-assisted sulfation roasting, characterized in that, The specific steps are as follows: (1) Quartz ore is crushed to a particle size ≤10mm to obtain coarse quartz particles; (2) Mix coarse quartz particles with solid reducing agent evenly, place them in a high-temperature and high-energy ball mill, and dry ball mill them for 2 to 10 hours under an inert atmosphere and at a temperature of 400 to 900°C to cause cracks in the coarse quartz particles and expose internal impurities. At the same time, the solid reducing agent reduces and activates the impurities in the coarse quartz particles to obtain ball-milled activated coarse quartz particles. (3) Ball milling activated quartz coarse particles and sieving to obtain activated quartz powder of 45~180 mesh; (4) Place activated quartz powder in a rotary furnace and introduce sulfur oxide gas, or mix activated quartz powder with solid sulfation reagent evenly and place it in a rotary furnace for sulfation roasting for 1-5 hours to allow the impurities in the activated quartz powder to undergo deep sulfation conversion to obtain sulfated roasted quartz. (5) Sulfated roasted quartz is added to acid solution for acid leaching treatment, solid-liquid separation, and the solid is washed with deionized water and dried to obtain purified quartz.

2. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (2) The solid reducing agent is one or more of activated carbon, charcoal, and graphite, and the fixed carbon content in the solid reducing agent is not less than 85%.

3. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (2) The particle size of the solid reducing agent is ≤1mm, and the amount of solid reducing agent added is 0.5~10% of the mass of the coarse quartz particles.

4. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (2) The grinding media for dry ball milling are agate, zirconium oxide or corundum ceramic, the ball-to-material mass ratio is 10~20:1, and the ball milling speed is 300~800 rpm.

5. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (4) The sulfur oxide gas is SO3 gas or SO2-O2 mixture, the volume ratio of SO2 to O2 in SO2-O2 mixture is 0.2~4:1, the gas flow rate is 200~800 mL / min, and the sulfation roasting temperature is 300~700℃.

6. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (4) The solid sulfation reagent is ammonium sulfate or ammonium bisulfate. The amount of solid sulfation reagent added is 10-30% of the mass of activated quartz powder, and the sulfation roasting temperature is 300-400℃.

7. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (4) The rotation speed of the rotary furnace is 5~20 rpm.

8. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 1, characterized in that: Step (5) The acid solution is one or more of hydrochloric acid, sulfuric acid, and nitric acid, and the total concentration of the acid solution is 1~5 mol / L.

9. The method for purifying quartz by mechanochemical activation-assisted sulfation roasting according to claim 8, characterized in that: Step (5) The liquid-solid ratio of acid solution to sulfated roasted quartz is 4~10:1 mL:g, the acid leaching temperature is 50~100℃, the stirring rate is 5~15 rpm, and the time is 1~5 h.

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