Fluorosilazite microcrystalline glass prepared from fluorine-containing sludge and preparation method of fluorosilazite microcrystalline glass

Abstract

The invention discloses a fluosilicalite microcrystalline glass prepared from fluorine-containing sludge, and the fluosilicalite microcrystalline glass is prepared from the following raw materials in percentage by mass: 40 to 45 percent of SiO2, 0.05 to 0.55 percent of Al2O3, 4 to 10 percent of K2CO3, 12 to 14 percent of Na2CO3, 1 to 5 percent of CaCO3 and 25 to 35 percent of fluorine-containing sludge. The fluosilicalite microcrystalline glass disclosed by the invention not only has higher mechanical properties, but also can be used for effectively recycling the stacked fluorine-containing sludge and solidifying F <->, so that higher economic benefits can be obtained.

Description

Technical Field

[0001] This invention relates to the field of glass technology, specifically to a fluorosilicone alkali calcium silicate microcrystalline glass prepared using fluorinated sludge and its preparation method. Background Technology

[0002] Fluoride-containing sludge is a high-fluoride industrial solid waste generated during semiconductor manufacturing, photovoltaic industry, and fluorochemical production. The calcium fluoride content in this sludge can reach 40%-70%, and it also contains small amounts of heavy metals and organic pollutants. Calcium fluoride has low toxicity; however, if the sludge is not properly treated, it can lead to serious health problems. - It easily pollutes surface water, soil, and groundwater through rainwater leaching and surface runoff, and can be toxic to crop growth and some soil microorganisms. Furthermore, if F - Excessive levels of fluoride in the human body can cause health problems such as dental fluorosis and skeletal fluorosis. Therefore, the proper disposal and utilization of fluoride-containing sludge is of utmost importance. Due to the biotoxicity and mobility of fluorides, fluoride-containing sludge has been classified as hazardous waste (HW32 category). Traditional disposal methods often involve solidification and landfill, acid-base neutralization, or stockpiling, which result in high disposal costs, significant resource waste, and substantial potential environmental risks.

[0003] Fluorosilica-calcium silicate (FMS) glass, as a special type of glass-ceramic, possesses excellent mechanical properties, processability, and bioactivity, making it applicable in fields such as building decoration materials, disk substrates, and biomaterials. Due to the anisotropy of FMS crystals, the lath-like crystals interweave within the glass matrix. When cracks occur, this structure causes branching and deflection during crack propagation, significantly increasing the resistance to crack growth and thus greatly enhancing the strength of the glass-ceramic. Therefore, FMS glass-ceramic exhibits excellent mechanical properties, with a flexural strength reaching up to 300 MPa and a fracture toughness of 5.0 MPa·m½. Furthermore, the unique microstructure of FMS crystals endows the glass-ceramic with high strength, fracture toughness, and excellent biocompatibility and chemical stability, demonstrating great potential in applications such as dental and orthopedic biorepair materials.

[0004] Currently, there is limited research on the preparation of fluorosilicon-alkali calcium silicate microcrystalline glass using fluorinated sludge. The comprehensive utilization rate of fluorinated sludge is low, and the fluoride fixation effect of some reused products is poor, with fluoride migrating out under certain water or acid / alkali conditions. Therefore, it is necessary to explore an efficient and stable method for the reuse of fluorinated sludge. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a fluorosilicone alkali calcium silicate microcrystalline glass prepared using fluorine-containing sludge and a preparation method thereof.

[0006] This invention discloses a fluorosilicone alkali calcium silicate microcrystalline glass prepared using fluorine-containing sludge. The raw material composition of the microcrystalline glass, by mass percentage, includes: SiO2 40-45%, Al2O3 0.05-0.55%, K2CO3 4-10%, Na2CO3 12-14%, CaCO3 1-5%, fluoride-containing sludge 25-35%.

[0007] As a further improvement of the present invention, the fluorine in the fluorine-containing sludge is in the form of calcium fluoride, and also includes calcium sulfate, calcium carbonate, silicon dioxide, aluminum oxide, sodium carbonate and potassium carbonate.

[0008] As a further improvement of the present invention, the content ranges of each component in the fluoride-containing sludge by mass percentage are as follows: CaSO4 3.5-8.5%, Al2O3 4.16-4.26%, SiO2 10-13.2%, Fe2O3 0.1-0.14%, CaF2 45.59-49.8%, MgO 1.4-1.8%, K2O 0.02-0.04%, Na2O 0.2-0.3%, TiO2 0.02-0.04%, SrO 0.20-0.21%, BaO 0.48-0.61%, B2O3 0.20-0.25%, CeO2 0.44-0.54%, P2O5 0.18-0.26%, CaCO3 28.60-28.87%, La2O3 0.20-0.22%.

[0009] This invention also provides a method for preparing fluorosilicone alkali calcium silicate microcrystalline glass, comprising: Step 1: Pre-treat the fluoride-containing sludge, the pre-treatment including drying, grinding and sieving; Step 2: Weigh the pretreated fluoride-containing sludge and the required additives according to the preset ratio, mix them evenly, and obtain the batching material; Step 3: Place the batch materials for melting to obtain a homogeneous glass melt; Step 4: Pour the molten glass into a mold to form it, and transfer it to a muffle furnace for annealing to obtain a uniform and stable opalescent glass; Step 5: Heat the opaque glass to the preset temperature and hold it at that temperature for a preset time, then let it cool naturally to room temperature to obtain fluorosilicone alkali calcium stone microcrystalline glass.

[0010] As a further improvement of the present invention, in step 1, the drying temperature range is 100-110℃ for 24 hours, the grinding conditions are to put the dried sample into a ball mill jar and grind it for 6 hours at a material-to-ball ratio of 1:2, and the sieve aperture range is 40-100 mesh.

[0011] As a further improvement of the present invention, in step 2, the mixing condition is to put the weighed ingredients into a mixing tank and mix for 12 hours.

[0012] As a further improvement of the present invention, in step 3, the melting temperature is 1200~1400℃ and the melting time is 50~70min; preferably, the melting temperature is 1250℃ and the melting time is 60min.

[0013] As a further improvement of the present invention, in step 4, the specific annealing process in the muffle furnace is as follows: annealing in a muffle furnace at 480-520°C for 1-3 hours, and then cooling to room temperature with the furnace.

[0014] As a further improvement of the present invention, in step 5, the temperature is increased to 700-950°C at a heating rate of 5-10 K / min and held for 50-70 min.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The fluorosilicone alkali calcium stone microcrystalline glass of the present invention has high mechanical properties, especially fracture toughness; it has a relatively stable curing effect on fluoride ions, can efficiently and stably treat fluoride-containing sludge, and has a significant volume reduction effect; at the same time, its appearance presents a milky white jade texture, which can replace high-grade decorative marble or artificial stone building materials, and has great application prospects in building decoration materials. Attached Figure Description

[0016] Figure 1 Physical images of microcrystalline glass with different doping amounts prepared according to the present invention and comparative physical images of the same invention; Figure 2 XRD patterns of the microcrystalline glass prepared in this invention and comparative examples; Figure 3 Indentation diagram of the fracture toughness of the microcrystalline glass prepared in this invention; Figure 4 The image shows the microcrystalline glass prepared according to the present invention and a comparative fracture toughness diagram. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The present invention will now be described in further detail with reference to the accompanying drawings: This invention provides a fluorosilicon-alkali calcium silicate microcrystalline glass prepared using fluorinated sludge. The raw material composition of the microcrystalline glass, by mass percentage, includes: SiO2 40-45%, Al2O3 0.05-0.55%, K2CO3 4-10%, Na2CO3 12-14%, CaCO3 1-5%, and fluorinated sludge 25-35%. The fluorine in the fluorine-containing sludge is in the form of calcium fluoride, and also includes calcium sulfate, calcium carbonate, silicon dioxide, aluminum oxide, sodium carbonate and potassium carbonate. The content ranges of each component in the fluoride-containing sludge, by mass percentage, are as follows: CaSO4 3.5-8.5%, Al2O3 4.16-4.26%, SiO2 10-13.2%, Fe2O3 0.1-0.14%, CaF2 45.59-49.8%, MgO 1.4-1.8%, K2O 0.02-0.04%, Na2O 0.2-0.3%, TiO2 0.02-0.04%, SrO 0.20-0.21%, BaO 0.48-0.61%, B2O3 0.20-0.25%, CeO2 0.44-0.54%, P2O5 0.18-0.26%, CaCO3 28.60-28.87%, La2O3 0.20-0.22%.

[0019] This invention also provides a method for preparing fluorosilicone alkali calcium silicate microcrystalline glass, comprising: Step 1: Pre-treat the fluoride-containing sludge. The pre-treatment includes drying, grinding and sieving. The drying temperature range is 100-110℃, and the drying time is 24 hours. The grinding conditions are: put the dried sludge into a ball mill jar and grind it for 6 hours at a material-to-ball ratio of 1:2. The sieve aperture range is 40-100 mesh.

[0020] Step 2: Weigh the pretreated fluoride-containing sludge and the required additives according to the preset ratio, mix them evenly to obtain the batch material; wherein, the mixing condition is to put the weighed batch materials into the mixing tank and mix for 12 hours.

[0021] Step 3: Place the batch material in an alumina crucible and melt it under sealed conditions to obtain a homogeneous glass melt; wherein the melting temperature is 1200~1400℃ and the melting time is 50~70min; preferably, the melting temperature is 1250℃ and the melting time is 60min.

[0022] Step 4: Pour the molten glass into a mold to form it, and then transfer it to a muffle furnace for annealing to obtain a uniform and stable milky white raw glass. The specific annealing process in the muffle furnace is as follows: anneal in a muffle furnace at 480-520℃ for 1-3 hours, and then cool to room temperature with the furnace.

[0023] Step 5: Heat the opaque glass to 700-950℃ at a heating rate of 5-10K / min, hold it at that temperature for 50-70min (preferably 60min), and then let it cool naturally to room temperature to obtain fluorosilicone alkali calcium silicate microcrystalline glass.

[0024] Table 1 shows the composition of the fluorosilicone alkali calcium silicate microcrystalline glass in a specific embodiment.

[0025]

[0026] The specific composition of the fluoride-containing sludge in Examples 1-4 is as follows: CaSO4 3.52%, Al2O3 4.25%, SiO2 10.21%, Fe2O3 0.11%, CaF2 49.3%, MgO 1.64%, K2O 0.02%, Na2O 0.28%, TiO2 0.03%, SrO 0.21%, BaO 0.60%, B2O3 0.25%, CeO2 0.44%, P2O5 0.19%, CaCO3 28.75%, and La2O3 0.20%.

[0027] The preparation methods of the fluorosilicone alkali calcium silicate microcrystalline glass in Examples 1-2 are as follows: S1. Drying: The fluoride-containing sludge is placed in a drying oven and dried at 105°C to obtain dried sludge blocks.

[0028] S2. Grinding: The dried sludge blocks are put into a ball mill and ground at a material-to-ball ratio of 1:2 for 9 hours to obtain sludge powder, which is then passed through a 100-mesh sieve.

[0029] S3. Ingredients: Weigh the corresponding raw materials according to the chemical composition ratios in the examples in Table 1.

[0030] S4. Mixing: Place the weighed batch material on a mixer and mix for 12 hours to obtain a uniformly mixed batch material.

[0031] S5. Melting: The mixed batch is placed in a high-temperature furnace at 1250℃ and heated to melt for 1 hour to obtain molten glass.

[0032] S6. Molding: The molten glass is quickly poured into a graphite mold to obtain a shaped sample.

[0033] S7. Annealing: Place the glass formed in the graphite mold into an annealing furnace at 500℃ and keep it at that temperature for at least 3 hours. Then, let it cool to room temperature with the furnace to obtain the original glass.

[0034] S8. Heat treatment: The obtained glass sample is placed in a muffle furnace and heated to 500℃ at a heating rate of 10K / min, and then heated to 800℃ at a rate of 5℃ / min and held for 1h to obtain fluorosilicone alkali calcium silicate microcrystalline glass.

[0035] The preparation methods of the fluorosilicone alkali calcium silicate microcrystalline glass in Examples 3-4 are as follows: S1. Drying: The fluoride-containing sludge is placed in a drying oven and dried at 105°C to obtain dried sludge blocks.

[0036] S2. Grinding: The dried sludge blocks are put into a ball mill and ground at a material-to-ball ratio of 1:2 for 9 hours to obtain sludge powder, which is then passed through a 100-mesh sieve.

[0037] S3. Ingredients: Weigh the corresponding raw materials according to the chemical composition ratios in the examples in Table 1.

[0038] S4. Mixing: Place the weighed batch material on a mixer and mix for 12 hours to obtain a uniformly mixed batch material.

[0039] S5. Melting: The mixed batch is placed in a high-temperature furnace at 150°C and heated to melt for 1 hour to obtain molten glass.

[0040] S6. Molding: The molten glass is quickly poured into a graphite mold to obtain a shaped sample.

[0041] S7. Annealing: Place the glass formed in the graphite mold into an annealing furnace at 500℃ and keep it at that temperature for at least 3 hours. Then, let it cool to room temperature with the furnace to obtain the original glass.

[0042] S8. Heat treatment: The obtained glass sample is placed in a muffle furnace and heated to 500℃ at a heating rate of 10K / min, and then heated to 750℃ at a heating rate of 5℃ / min and held for 1h to obtain fluorosilicone alkali calcium silicate microcrystalline glass.

[0043] Table 2 shows the composition of the comparative fluorosilicone alkali calcium silicate microcrystalline glass.

[0044]

[0045] The specific composition of the fluoride-containing sludge in Comparative Examples 1-4 is as follows: CaSO4 3.52%, Al2O3 4.25%, SiO2 10.21%, Fe2O3 0.11%, CaF2 49.3%, MgO 1.64%, K2O 0.02%, Na2O 0.28%, TiO2 0.03%, SrO 0.21%, BaO 0.60%, B2O3 0.25%, CeO2 0.44%, P2O5 0.19%, CaCO3 28.75%, and La2O3 0.20%.

[0046] The preparation methods of the fluorosilicone alkali calcium silicate microcrystalline glass in Comparative Examples 1-4 are as follows: S1. Drying: The fluoride-containing sludge is placed in a drying oven and dried at 105°C to obtain dried sludge blocks.

[0047] S2. Grinding: The dried sludge blocks are put into a ball mill and ground at a material-to-ball ratio of 1:2 for 9 hours to obtain sludge powder, which is then passed through a 100-mesh sieve.

[0048] S3. Ingredients: Weigh the corresponding raw materials according to the chemical composition ratios in the examples in Table 1.

[0049] S4. Mixing: Place the weighed batch material on a mixer and mix for 12 hours to obtain a uniformly mixed batch material.

[0050] S5. Melting: The mixed batch is placed in a high-temperature furnace at 1250℃ and heated to melt for 1 hour to obtain molten glass.

[0051] S6. Molding: The molten glass is quickly poured into a graphite mold to obtain a shaped sample.

[0052] S7. Annealing: Place the glass formed in the graphite mold into an annealing furnace at 500℃ and keep it at that temperature for at least 3 hours. Then, cool it to room temperature with the furnace to obtain the original glass sample for comparison.

[0053] Depend on Figure 1 As can be seen, the embodiments of the present invention are all milky white microcrystalline glass, the surface of which has lost the original luster of glass, and the texture is more similar to that of ceramic; the comparative sample shows milky white and milky yellow glass luster, and retains the glass luster, and the unique luster reflection of glass can be seen under light. Figure 2 XRD patterns for examples and comparative examples, from Figure 2 As can be seen, calcium fluoride crystals precipitate in the comparative glass sample, while after heat treatment, the main crystalline phase in the example sample changes from calcium fluoride to fluorosilicic alkali calcium stone crystals. Figure 3 The fracture toughness indentation diagram of this invention shows that the effectiveness of the indentation and the cracks generated at the four vertices of the indentation complies with the requirements of standard GB / T16534. Figure 4 This is a schematic diagram of the fracture toughness results of the embodiments and comparative examples of the present invention. The results show that the fracture toughness of the embodiments is better than that of the comparative examples. This is because the crystal structure of the fluorosilicone alkali calcium silicate microcrystalline glass is a lath-like crisscross structure. When a crack is generated, this structure can cause the crack to bifurcate and deflect during the propagation process, thereby greatly increasing the resistance to crack propagation. As a result, the fracture toughness of the embodiment samples is stronger than that of the comparative sample.

[0054] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fluorosilicone alkali calcium silicate microcrystalline glass prepared using fluorine-containing sludge, characterized in that, The raw material composition of the microcrystalline glass, by weight percentage, includes: SiO2 40-45%, Al2O3 0.05-0.55%, K2CO3 4-10%, Na2CO3 12-14%, CaCO3 1-5%, fluoride-containing sludge 25-35%.

2. The fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 1, characterized in that, The fluorine in the fluorine-containing sludge exists in the form of calcium fluoride, and also includes calcium sulfate, calcium carbonate, silicon dioxide, aluminum oxide, sodium carbonate, and potassium carbonate.

3. The fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 1, characterized in that, The content ranges of each component in the fluoride-containing sludge, by mass percentage, are as follows: CaSO4 3.5-8.5%, Al2O3 4.16-4.26%, SiO2 10-13.2%, Fe2O3 0.1-0.14%, CaF2 45.59-49.8%, MgO 1.4-1.8%, K2O 0.02-0.04%, Na2O 0.2-0.3%, TiO2 0.02-0.04%, SrO 0.20-0.21%, BaO 0.48-0.61%, B2O3 0.20-0.25%, CeO2 0.44-0.54%, P2O5 0.18-0.26%, CaCO3 28.60-28.87%, La2O3 0.20-0.22%.

4. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass according to any one of claims 1 to 3, characterized in that, include: Step 1: Pre-treat the fluoride-containing sludge, the pre-treatment including drying, grinding and sieving; Step 2: Weigh the pretreated fluoride-containing sludge and the required additives according to the preset ratio, mix them evenly, and obtain the batching material; Step 3: Place the batch materials for melting to obtain a homogeneous glass melt; Step 4: Pour the molten glass into a mold to form it, and transfer it to a muffle furnace for annealing to obtain a uniform and stable opalescent glass; Step 5: Heat the opaque glass to the preset temperature and hold it at that temperature for the preset time, then let it cool naturally to room temperature to obtain fluorosilicone alkali calcium crystal glass.

5. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 4, characterized in that, In step 1, the drying temperature range is 100-110℃, the drying time is 24 hours, and the grinding conditions are as follows: put the dried sludge into a ball mill jar and grind it for 6 hours at a material-to-ball ratio of 1:

2. The sieve aperture range is 40-100 mesh.

6. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 4, characterized in that, In step 2, the mixing condition is to put the weighed ingredients into a mixing tank and mix for 12 hours.

7. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 4, characterized in that, In step 3, the melting temperature is 1200~1400℃ and the melting time is 50~70min.

8. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 4, characterized in that, In step 4, the specific annealing process in the muffle furnace is as follows: annealing in a muffle furnace at 480-520℃ for 1-3 hours, followed by cooling to room temperature with the furnace.

9. The method for preparing fluorosilicone alkali calcium silicate microcrystalline glass as described in claim 4, characterized in that, In step 5, the temperature is increased to 700-950℃ at a heating rate of 5-10K / min, and held for 50-70 minutes.

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