Fluorite crystal impurity leaching solution based on microbial metabolites and preparation process

Abstract

This invention discloses a fluorite crystal impurity leachate based on microbial metabolites and its preparation process, relating to the field of fluorite crystal impurity leachate preparation technology. The raw materials include: microbial metabolic fermentation broth, chelation solution, synergistic solution, modified glucosamine magnesium phosphate microsphere slurry, modified hydroxyapatite nanosphere slurry, modified hydroxypropyl methylcellulose ether slurry, and deionized water. In this invention, the addition of modified glucosamine magnesium phosphate microsphere slurry significantly improves the dispersibility and stability of the microspheres, enabling in-situ adsorption of free fluoride ions in the system, eliminating the inhibitory effect of fluoride ions on microbial metabolism, and simultaneously helping to stabilize the pH of the leaching system, providing a suitable environment for impurity leaching. It also synergistically enhances the solid-liquid separation effect without reducing the grade of fluorite concentrate. The addition of modified hydroxyapatite nanosphere slurry provides excellent selective adsorption capacity, preferentially adsorbing difficult-to-remove impurities such as quartz and silicates, improving the precision of deep impurity removal.

Description

Technical Field

[0001] This invention relates to the field of fluorite crystal impurity leachate preparation technology, and particularly to fluorite crystal impurity leachate based on microbial metabolites and its preparation process. Background Technology

[0002] Fluorite crystal impurity leaching solution refers to the solution produced during the purification and processing of fluorite ore (mainly composed of calcium fluoride CaF2) by chemical methods such as acid leaching (commonly hydrochloric acid or sulfuric acid) to remove impurity minerals (such as calcite, carbonates, etc.) from the ore.

[0003] Traditional fluorite impurity leaching systems suffer from numerous problems, including excessive fluorite loss due to strong acid corrosion, insufficient activity of microbial metabolites due to fluoride ion interference, poor dispersion and agglomeration of inorganic microsphere raw materials, low precision and selectivity in the removal of silicate and iron-calcium impurities, inability of protective materials to form a stable acid-resistant film on the fluorite surface, large fluctuations in pH and viscosity of the leaching system, slow solid-liquid separation speed, easy secondary deposition of impurities, and unsatisfactory flotation recovery rate. Therefore, this invention provides a fluorite crystal impurity leaching solution based on microbial metabolites and its preparation process. Summary of the Invention

[0004] The main objective of this invention is to provide a fluorite crystal impurity leachate with low fluoride ion residue and high SiO2 leaching rate based on microbial metabolites, and its preparation process, which can be applied to the fluorite crystal impurity leachate based on microbial metabolites and its preparation process.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] This invention provides a fluorite crystal impurity leachate based on microbial metabolites, wherein the fluorite crystal impurity leachate based on microbial metabolites comprises the following raw materials: 45-55 parts of microbial metabolic fermentation broth, 0.25-0.35 parts of chelating solution, 0.09-0.11 parts of synergistic solution, 0.6-0.8 parts of modified glucosamine magnesium phosphate microsphere slurry, 0.6-0.8 parts of modified hydroxyapatite nanosphere slurry, 0.24-0.26 parts of modified hydroxypropyl methylcellulose ether slurry, and 43-49 parts of deionized water.

[0007] Furthermore, the synergistic solution is composed of L-malic acid and vitamin B7 mixed in a mass ratio of 9:1.

[0008] L-malic acid purity ≥ 99%, levorotatory form.

[0009] Vitamin B7 has a purity of ≥98% and is water-soluble.

[0010] The synergistic solution can activate and enhance the leaching activity of organic acids metabolized by microorganisms, prolong the effective action period of the leachate, and form a weak protective adsorption layer on the surface of fluorite to reduce acid dissolution loss of fluorite. At the same time, biotin can improve the biocompatibility of the system and avoid inhibiting the activity of microbial metabolites, thus taking into account both leaching enhancement and basic protection of fluorite.

[0011] Furthermore, the chelating solution is prepared by mixing phytic acid aqueous solution and γ-aminopropyltriethoxysilane in a mass ratio of 19:1;

[0012] The phytic acid aqueous solution has a mass concentration of 50%.

[0013] γ-aminopropyltriethoxysilane has a purity of ≥98% and is a colorless, transparent liquid.

[0014] The chelating solution combines the strong metal ion chelating ability of phytic acid with the mineral surface affinity of silane coupling agents. It can quickly chelate impurity ions such as iron, calcium, and magnesium in the system, preventing impurities from being deposited secondary on the fluorite surface. At the same time, it can activate the impurity mineral interface and improve the leaching rate. The raw materials are all commercially available conventional chemicals. The compounding process is simple, and it is more industrially feasible to replace complex modified chelates without affecting the crystal structure of fluorite.

[0015] Furthermore, the preparation of the microbial metabolic fermentation broth includes the following steps:

[0016] A1. Mix glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate and deionized water, set the speed to 250 rpm and stir for 18 minutes. Add deionized water and stir, set the speed to 200 rpm and stir for 3 minutes to obtain the culture medium.

[0017] A2. Mix and stir the Aspergillus niger spore powder and deionized water at 150 rpm for 2 minutes to obtain a suspension.

[0018] A3. Add the suspension to the culture medium and stir to ferment. Set the temperature to 30℃, the rotation speed to 180 rpm, and ferment for 72 hours. Filter with a 200-mesh filter cloth to remove mycelium and obtain the microbial metabolic fermentation broth.

[0019] The glucose is food grade with a purity of ≥99%.

[0020] The corn steep liquor powder is a dry type with a water solubility of ≥95% and is free from mold.

[0021] Potassium dihydrogen phosphate is industrial grade with a purity of ≥98%.

[0022] Magnesium sulfate heptahydrate is industrial grade with a purity of ≥98%.

[0023] Aspergillus niger spore powder spore count ≥10 9 CFU / g.

[0024] Microbial metabolic fermentation broth uses organic acids such as oxalic acid, citric acid, and gluconic acid produced by Aspergillus niger as its core effective components. These are the main functional components of the leachate and can target and decompose impurities such as calcite, dolomite, and iron oxides in fluorite ore at room temperature. The leaching conditions are mild and energy consumption is low. The bio-based source is green and biodegradable and will not cause excessive erosion to the fluorite body. At the same time, it can meet the impurity removal needs of complex low-grade fluorite ore and has a wide range of applications.

[0025] Furthermore, the mass ratio of glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, deionized water, and added deionized water in A1 is 100:20:5:2:800:200.

[0026] The mass ratio of Aspergillus niger spore powder to deionized water in A2 is 1:233;

[0027] The mass ratio of the suspension to the culture medium is 1:28.5.

[0028] Furthermore, the preparation of the modified glucosamine magnesium phosphate microsphere slurry includes the following steps: mixing glucosamine magnesium phosphate microspheres and deionized water, stirring at 350 rpm for 10 minutes, adding sodium polyaspartate and stirring at 250 rpm for 40 minutes, adding quaternized dextran and stirring at 250 rpm for 30 minutes to obtain the modified glucosamine magnesium phosphate microsphere slurry.

[0029] Furthermore, the mass ratio of the glucosamine magnesium phosphate microspheres, deionized water, sodium polyaspartate, and quaternized dextran is 8:0.32:0.2:91.48.

[0030] The particle size of the glucosamine magnesium phosphate microspheres is 1-5 μm.

[0031] The molecular weight of sodium polyaspartate is <5000.

[0032] The degree of substitution of quaternized dextran is <0.1.

[0033] Further, the preparation of the modified hydroxyapatite nanosphere slurry includes the following steps: mixing and stirring nano-hydroxyapatite microspheres and deionized water at a speed of 350 rpm for 10 minutes, adding aminotrimethylenephosphonic acid and stirring at a speed of 250 rpm for 60 minutes, adding carboxymethyl chitosan oligosaccharide and stirring at a speed of 250 rpm for 40 minutes to obtain the modified hydroxyapatite nanosphere slurry;

[0034] The mass ratio of the nano-hydroxyapatite microspheres, deionized water, aminotrimethylenephosphonic acid, and carboxymethyl chitosan oligosaccharide is 8:91.1:0.6:0.3.

[0035] The nano-hydroxyapatite microspheres have a particle size of 20-50 nm and a purity of ≥99%.

[0036] The active ingredient content of aminotrimethylenephosphonic acid is ≥50%.

[0037] Carboxymethyl chitosan oligosaccharide has a molecular weight of <5000 and a degree of substitution of 0.6-0.8.

[0038] Further, the preparation of the modified hydroxypropyl methylcellulose ether slurry includes the following steps: mixing hydroxypropyl methylcellulose ether and deionized water, stirring at 250 rpm for 30 minutes, adding isoascorbic acid phosphonate and stirring at 250 rpm for 15 minutes, adding lactic acid oligomer and stirring at 250 rpm for 20 minutes to obtain the modified hydroxypropyl methylcellulose ether slurry;

[0039] The mass ratio of the hydroxypropyl methylcellulose ether, deionized water, isoascorbic acid phosphonate, and lactic acid oligomer is 2:97.5:0.3:0.2.

[0040] The viscosity of hydroxypropyl methylcellulose ether is 50-100 mPa·s (2% aqueous solution).

[0041] The purity of isoascorbic acid phosphonate is ≥98%.

[0042] The molecular weight of lactic acid oligomers is <1000.

[0043] Secondly, the present invention provides a preparation process for a fluorite crystal impurity leachate based on microbial metabolites. The preparation process includes the following steps: mixing and stirring microbial metabolic fermentation broth and deionized water at a speed of 250 rpm for 5 minutes; adding chelating solution and stirring at a speed of 250 rpm for 3 minutes; adding synergistic solution and stirring at a speed of 250 rpm for 3 minutes; adding modified glucosamine magnesium phosphate microsphere slurry and stirring at a speed of 250 rpm for 5 minutes; adding modified hydroxyapatite nanosphere slurry and stirring at a speed of 250 rpm for 5 minutes; and adding modified hydroxypropyl methylcellulose ether slurry and stirring at a speed of 250 rpm for 5 minutes to obtain a fluorite crystal impurity leachate based on microbial metabolites.

[0044] The present invention has the following beneficial effects:

[0045] 1. In this invention, modified glucosamine magnesium phosphate microsphere slurry is added, which greatly improves the dispersibility and stability of the microspheres. It can adsorb free fluoride ions in the system in situ, eliminate the inhibitory effect of fluoride ions on microbial metabolism, and at the same time help stabilize the pH of the leaching system, providing a suitable environment for impurity leaching. It can also synergistically improve the solid-liquid separation effect without reducing the grade of fluorite concentrate.

[0046] 2. In this invention, modified hydroxyapatite nanosphere slurry is added, which has excellent selective adsorption capacity and can preferentially adsorb difficult-to-remove impurities such as quartz and silicates, thereby improving the accuracy of deep impurity removal. The nano-sized particles can penetrate into the gaps between mineral grains, enhancing the impurity removal effect of complex embedded fluorite ore. It has stable chemical properties and does not react adversely with the main body of the leachate.

[0047] 3. In this invention, modified hydroxypropyl methylcellulose ether slurry is added, which can form an ultra-thin and uniform physical protective film on the surface of fluorite, precisely blocking acid erosion, significantly reducing fluorite dissolution loss and improving recovery rate. The protective film does not hinder the leaching of impurities, has excellent acid resistance and biocompatibility, and does not damage the overall stability of the system. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0049] It should be noted that all raw materials used in the following experiments are commercially available.

[0050] Example 1: Fluorite crystal impurity leachate based on microbial metabolites. The fluorite crystal impurity leachate based on microbial metabolites comprises the following raw materials: 45 parts microbial metabolic fermentation broth, 0.25 parts chelating solution, 0.09 parts synergistic solution, 0.6 parts modified glucosamine magnesium phosphate microsphere slurry, 0.6 parts modified hydroxyapatite nanosphere slurry, 0.24 parts modified hydroxypropyl methylcellulose ether slurry, and 43 parts deionized water.

[0051] The synergistic solution is a mixture of L-malic acid and vitamin B7 in a mass ratio of 9:1.

[0052] The chelating solution was prepared by mixing phytic acid aqueous solution and γ-aminopropyltriethoxysilane in a mass ratio of 19:1.

[0053] The phytic acid aqueous solution has a mass concentration of 50%.

[0054] The preparation of microbial metabolic fermentation broth includes the following steps:

[0055] A1. Mix glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate and deionized water, set the speed to 250 rpm and stir for 18 minutes. Add deionized water and stir, set the speed to 200 rpm and stir for 3 minutes to obtain the culture medium.

[0056] A2. Mix and stir the Aspergillus niger spore powder and deionized water at 150 rpm for 2 minutes to obtain a suspension.

[0057] A3. Add the suspension to the culture medium and stir to ferment. Set the temperature to 30℃, the rotation speed to 180 rpm, and ferment for 72 hours. Filter with a 200-mesh filter cloth to remove mycelium and obtain the microbial metabolic fermentation broth.

[0058] The mass ratio of glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, deionized water, and added deionized water in A1 is 100:20:5:2:800:200.

[0059] The mass ratio of Aspergillus niger spore powder to deionized water in A2 is 1:233;

[0060] The mass ratio of suspension to culture medium was 1:28.5.

[0061] The preparation of modified glucosamine magnesium phosphate microsphere slurry includes the following steps: glucosamine magnesium phosphate microspheres and deionized water are mixed and stirred at 350 rpm for 10 minutes; sodium polyaspartate is added and stirred at 250 rpm for 40 minutes; quaternized dextran is added and stirred at 250 rpm for 30 minutes to obtain modified glucosamine magnesium phosphate microsphere slurry.

[0062] The mass ratio of glucosamine magnesium phosphate microspheres, deionized water, sodium polyaspartate, and quaternized dextran was 8:0.32:0.2:91.48.

[0063] The preparation of modified hydroxyapatite nanosphere slurry includes the following steps: mixing nano-hydroxyapatite microspheres and deionized water, stirring at 350 rpm for 10 minutes, adding aminotrimethylenephosphonic acid and stirring at 250 rpm for 60 minutes, adding carboxymethyl chitosan oligosaccharide and stirring at 250 rpm for 40 minutes to obtain modified hydroxyapatite nanosphere slurry;

[0064] The mass ratio of nano-hydroxyapatite microspheres, deionized water, aminotrimethylenephosphonic acid, and carboxymethyl chitosan oligosaccharide was 8:91.1:0.6:0.3.

[0065] The preparation of modified hydroxypropyl methylcellulose ether slurry includes the following steps: hydroxypropyl methylcellulose ether and deionized water are mixed and stirred at 250 rpm for 30 minutes; isoascorbic acid phosphonate is added and stirred at 250 rpm for 15 minutes; lactic acid oligomer is added and stirred at 250 rpm for 20 minutes to obtain modified hydroxypropyl methylcellulose ether slurry.

[0066] The mass ratio of hydroxypropyl methylcellulose ether, deionized water, isoascorbic acid phosphonate and lactic acid oligomer is 2:97.5:0.3:0.2.

[0067] The preparation process of fluorite crystal impurity leachate based on microbial metabolites includes the following steps: mixing and stirring microbial metabolic fermentation broth and deionized water at a speed of 250 rpm for 5 minutes; adding chelating solution and stirring at a speed of 250 rpm for 3 minutes; adding synergistic solution and stirring at a speed of 250 rpm for 3 minutes; adding modified glucosamine magnesium phosphate microsphere slurry and stirring at a speed of 250 rpm for 5 minutes; adding modified hydroxyapatite nanosphere slurry and stirring at a speed of 250 rpm for 5 minutes; and adding modified hydroxypropyl methylcellulose ether slurry and stirring at a speed of 250 rpm for 5 minutes to obtain fluorite crystal impurity leachate based on microbial metabolites.

[0068] Example 2: Fluorite crystal impurity leachate based on microbial metabolites. The fluorite crystal impurity leachate based on microbial metabolites comprises the following raw materials: 50 parts microbial metabolic fermentation broth, 0.3 parts chelating solution, 0.1 parts synergistic solution, 0.7 parts modified glucosamine magnesium phosphate microsphere slurry, 0.7 parts modified hydroxyapatite nanosphere slurry, 0.25 parts modified hydroxypropyl methylcellulose ether slurry, and 46 parts deionized water.

[0069] The synergistic solution is a mixture of L-malic acid and vitamin B7 in a mass ratio of 9:1.

[0070] The chelating solution was prepared by mixing phytic acid aqueous solution and γ-aminopropyltriethoxysilane in a mass ratio of 19:1.

[0071] The phytic acid aqueous solution has a mass concentration of 50%.

[0072] The preparation of microbial metabolic fermentation broth includes the following steps:

[0073] A1. Mix glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate and deionized water, set the speed to 250 rpm and stir for 18 minutes. Add deionized water and stir, set the speed to 200 rpm and stir for 3 minutes to obtain the culture medium.

[0074] A2. Mix and stir the Aspergillus niger spore powder and deionized water at 150 rpm for 2 minutes to obtain a suspension.

[0075] A3. Add the suspension to the culture medium and stir to ferment. Set the temperature to 30℃, the rotation speed to 180 rpm, and ferment for 72 hours. Filter with a 200-mesh filter cloth to remove mycelium and obtain the microbial metabolic fermentation broth.

[0076] The mass ratio of glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, deionized water, and added deionized water in A1 is 100:20:5:2:800:200.

[0077] The mass ratio of Aspergillus niger spore powder to deionized water in A2 is 1:233;

[0078] The mass ratio of suspension to culture medium was 1:28.5.

[0079] The preparation of modified glucosamine magnesium phosphate microsphere slurry includes the following steps: glucosamine magnesium phosphate microspheres and deionized water are mixed and stirred at 350 rpm for 10 minutes; sodium polyaspartate is added and stirred at 250 rpm for 40 minutes; quaternized dextran is added and stirred at 250 rpm for 30 minutes to obtain modified glucosamine magnesium phosphate microsphere slurry.

[0080] The mass ratio of glucosamine magnesium phosphate microspheres, deionized water, sodium polyaspartate, and quaternized dextran was 8:0.32:0.2:91.48.

[0081] The preparation of modified hydroxyapatite nanosphere slurry includes the following steps: mixing nano-hydroxyapatite microspheres and deionized water, stirring at 350 rpm for 10 minutes, adding aminotrimethylenephosphonic acid and stirring at 250 rpm for 60 minutes, adding carboxymethyl chitosan oligosaccharide and stirring at 250 rpm for 40 minutes to obtain modified hydroxyapatite nanosphere slurry;

[0082] The mass ratio of nano-hydroxyapatite microspheres, deionized water, aminotrimethylenephosphonic acid, and carboxymethyl chitosan oligosaccharide was 8:91.1:0.6:0.3.

[0083] The preparation of modified hydroxypropyl methylcellulose ether slurry includes the following steps: hydroxypropyl methylcellulose ether and deionized water are mixed and stirred at 250 rpm for 30 minutes; isoascorbic acid phosphonate is added and stirred at 250 rpm for 15 minutes; lactic acid oligomer is added and stirred at 250 rpm for 20 minutes to obtain modified hydroxypropyl methylcellulose ether slurry.

[0084] The mass ratio of hydroxypropyl methylcellulose ether, deionized water, isoascorbic acid phosphonate and lactic acid oligomer is 2:97.5:0.3:0.2.

[0085] The preparation process of fluorite crystal impurity leachate based on microbial metabolites includes the following steps: mixing and stirring microbial metabolic fermentation broth and deionized water at a speed of 250 rpm for 5 minutes; adding chelating solution and stirring at a speed of 250 rpm for 3 minutes; adding synergistic solution and stirring at a speed of 250 rpm for 3 minutes; adding modified glucosamine magnesium phosphate microsphere slurry and stirring at a speed of 250 rpm for 5 minutes; adding modified hydroxyapatite nanosphere slurry and stirring at a speed of 250 rpm for 5 minutes; and adding modified hydroxypropyl methylcellulose ether slurry and stirring at a speed of 250 rpm for 5 minutes to obtain fluorite crystal impurity leachate based on microbial metabolites.

[0086] Example 3: Fluorite crystal impurity leachate based on microbial metabolites. The fluorite crystal impurity leachate based on microbial metabolites comprises the following raw materials: 55 parts microbial metabolic fermentation broth, 0.35 parts chelation solution, 0.11 parts synergistic solution, 0.8 parts modified glucosamine magnesium phosphate microsphere slurry, 0.8 parts modified hydroxyapatite nanosphere slurry, 0.26 parts modified hydroxypropyl methylcellulose ether slurry, and 49 parts deionized water.

[0087] The synergistic solution is a mixture of L-malic acid and vitamin B7 in a mass ratio of 9:1.

[0088] The chelating solution was prepared by mixing phytic acid aqueous solution and γ-aminopropyltriethoxysilane in a mass ratio of 19:1.

[0089] The phytic acid aqueous solution has a mass concentration of 50%.

[0090] The preparation of microbial metabolic fermentation broth includes the following steps:

[0091] A1. Mix glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate and deionized water, set the speed to 250 rpm and stir for 18 minutes. Add deionized water and stir, set the speed to 200 rpm and stir for 3 minutes to obtain the culture medium.

[0092] A2. Mix and stir the Aspergillus niger spore powder and deionized water at 150 rpm for 2 minutes to obtain a suspension.

[0093] A3. Add the suspension to the culture medium and stir to ferment. Set the temperature to 30℃, the rotation speed to 180 rpm, and ferment for 72 hours. Filter with a 200-mesh filter cloth to remove mycelium and obtain the microbial metabolic fermentation broth.

[0094] The mass ratio of glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, deionized water, and added deionized water in A1 is 100:20:5:2:800:200.

[0095] The mass ratio of Aspergillus niger spore powder to deionized water in A2 is 1:233;

[0096] The mass ratio of suspension to culture medium was 1:28.5.

[0097] The preparation of modified glucosamine magnesium phosphate microsphere slurry includes the following steps: glucosamine magnesium phosphate microspheres and deionized water are mixed and stirred at 350 rpm for 10 minutes; sodium polyaspartate is added and stirred at 250 rpm for 40 minutes; quaternized dextran is added and stirred at 250 rpm for 30 minutes to obtain modified glucosamine magnesium phosphate microsphere slurry.

[0098] The mass ratio of glucosamine magnesium phosphate microspheres, deionized water, sodium polyaspartate, and quaternized dextran was 8:0.32:0.2:91.48.

[0099] The preparation of modified hydroxyapatite nanosphere slurry includes the following steps: mixing nano-hydroxyapatite microspheres and deionized water, stirring at 350 rpm for 10 minutes, adding aminotrimethylenephosphonic acid and stirring at 250 rpm for 60 minutes, adding carboxymethyl chitosan oligosaccharide and stirring at 250 rpm for 40 minutes to obtain modified hydroxyapatite nanosphere slurry;

[0100] The mass ratio of nano-hydroxyapatite microspheres, deionized water, aminotrimethylenephosphonic acid, and carboxymethyl chitosan oligosaccharide was 8:91.1:0.6:0.3.

[0101] The preparation of modified hydroxypropyl methylcellulose ether slurry includes the following steps: hydroxypropyl methylcellulose ether and deionized water are mixed and stirred at 250 rpm for 30 minutes; isoascorbic acid phosphonate is added and stirred at 250 rpm for 15 minutes; lactic acid oligomer is added and stirred at 250 rpm for 20 minutes to obtain modified hydroxypropyl methylcellulose ether slurry.

[0102] The mass ratio of hydroxypropyl methylcellulose ether, deionized water, isoascorbic acid phosphonate and lactic acid oligomer is 2:97.5:0.3:0.2.

[0103] The preparation process of fluorite crystal impurity leachate based on microbial metabolites includes the following steps: mixing and stirring microbial metabolic fermentation broth and deionized water at a speed of 250 rpm for 5 minutes; adding chelating solution and stirring at a speed of 250 rpm for 3 minutes; adding synergistic solution and stirring at a speed of 250 rpm for 3 minutes; adding modified glucosamine magnesium phosphate microsphere slurry and stirring at a speed of 250 rpm for 5 minutes; adding modified hydroxyapatite nanosphere slurry and stirring at a speed of 250 rpm for 5 minutes; and adding modified hydroxypropyl methylcellulose ether slurry and stirring at a speed of 250 rpm for 5 minutes to obtain fluorite crystal impurity leachate based on microbial metabolites.

[0104] Comparative Example 1: The difference between this comparative example and Example 1 is that:

[0105] Unmodified glucosamine magnesium phosphate microspheres were used in this comparative example.

[0106] Comparative Example 2: The difference between this comparative example and Example 1 is that:

[0107] Unmodified hydroxyapatite nanospheres were used in this comparative example.

[0108] Comparative Example 3 differs from Example 1 in that:

[0109] Unmodified hydroxypropyl methylcellulose ether was used in this comparative example.

[0110] Performance testing: The fluorite crystal impurity leachates based on microbial metabolites prepared in Examples 1, 2, 3, Comparative Examples 1, 2, and 3, as well as their preparation processes, were tested.

[0111] Performance testing: The relevant properties of the fluorite crystal impurity leachate and preparation process samples based on microbial metabolites provided in Examples 1-3 and Comparative Examples 1-3 were tested respectively, and the test data are recorded in Table 1 below:

[0112] Fluoride ion residue (mg / L) <![CDATA[SiO2 leaching rate (%)]]> Fluorite crystal facet retention rate (%) Example 1 7.6 91.2 98.1 Example 2 7.3 91.7 98.3 Example 3 7.5 91.6 98.4 Comparative Example 1 36.2 86.5 96.9 Comparative Example 2 13.2 71.8 95.4 Comparative Example 3 12.9 89.9 85.5

[0113] Based on the above data, the following conclusions can be drawn:

[0114] Among them, the test methods in GB / T7484-1987 were used to test the residual fluoride ions in fluorite crystal impurity leachates and preparation processes prepared using the test methods in Examples 1, 2, 3, Comparative Examples 1, 2, and 3.

[0115] The SiO2 leaching rate of fluorite crystal impurity leachates based on microbial metabolites and preparation processes prepared using the test methods in GB / T5195.8-2017 (Examples 1, 2, 3, Comparative Examples 1, 2, and 3) was tested.

[0116] The fluorite crystal surface retention rate of the fluorite crystal impurity leachate prepared by Examples 1, 2, 3, Comparative Examples 1, 2, and 3, based on the test methods in GB / T19587-2017, was tested.

[0117] Through the above demonstrations, the present invention is significantly superior to the control group in terms of fluoride ion residue, SiO2 leaching rate and fluorite crystal surface retention rate, thus verifying the advanced nature and rationality of the preparation process.

[0118] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0119] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A fluorite crystal impurity leachate based on microbial metabolites, characterized in that, The fluorite crystal impurity leachate based on microbial metabolites comprises the following raw materials: 45-55 parts microbial metabolic fermentation broth, 0.25-0.35 parts chelation solution, 0.09-0.11 parts synergistic solution, 0.6-0.8 parts modified glucosamine magnesium phosphate microsphere slurry, 0.6-0.8 parts modified hydroxyapatite nanosphere slurry, 0.24-0.26 parts modified hydroxypropyl methylcellulose ether slurry, and 43-49 parts deionized water.

2. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The synergistic solution is composed of L-malic acid and vitamin B7 in a mass ratio of 9:

1.

3. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The chelation solution is prepared by mixing phytic acid aqueous solution and γ-aminopropyltriethoxysilane in a mass ratio of 19:1; The phytic acid aqueous solution has a mass concentration of 50%.

4. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The preparation of the microbial metabolic fermentation broth includes the following steps: A1. Mix glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate and deionized water, add deionized water and stir to obtain the culture medium; A2. Mix and stir Aspergillus niger spore powder and deionized water to obtain a suspension; A3. Add the suspension to the culture medium and stir to ferment. Filter the mixture with a filter cloth to remove mycelium and obtain the microbial metabolic fermentation broth.

5. The fluorite crystal impurity leachate based on microbial metabolites according to claim 4, characterized in that, The mass ratio of glucose, corn steep liquor powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, deionized water, and added deionized water in A1 is 100:20:5:2:800:

200. The mass ratio of Aspergillus niger spore powder to deionized water in A2 is 1:233; The mass ratio of the suspension to the culture medium is 1:28.

5.

6. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The preparation of the modified glucosamine magnesium phosphate microsphere slurry includes the following steps: Glucosamine magnesium phosphate microspheres were mixed and stirred with deionized water, then sodium polyaspartate was added and stirred, followed by the addition of quaternized dextran and stirred to obtain a modified glucosamine magnesium phosphate microsphere slurry.

7. The fluorite crystal impurity leachate based on microbial metabolites according to claim 6, characterized in that, The mass ratio of glucosamine magnesium phosphate microspheres, deionized water, sodium polyaspartate, and quaternized dextran is 8:0.32:0.2:91.

48.

8. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The preparation of the modified hydroxyapatite nanosphere slurry includes the following steps: Nano-hydroxyapatite microspheres and deionized water were mixed and stirred, aminotrimethylene phosphonic acid was added and stirred, and carboxymethyl chitosan oligosaccharide was added and stirred to obtain a modified hydroxyapatite nanosphere slurry. The mass ratio of the nano-hydroxyapatite microspheres, deionized water, aminotrimethylenephosphonic acid, and carboxymethyl chitosan oligosaccharide is 8:91.1:0.6:0.

3.

9. The fluorite crystal impurity leachate based on microbial metabolites according to claim 1, characterized in that, The preparation of the modified hydroxypropyl methylcellulose ether slurry includes the following steps: Hydroxypropyl methylcellulose ether and deionized water were mixed and stirred, isoascorbic acid phosphonate was added and stirred, lactic acid oligomer was added and stirred to obtain modified hydroxypropyl methylcellulose ether slurry; The mass ratio of the hydroxypropyl methylcellulose ether, deionized water, isoascorbic acid phosphonate, and lactic acid oligomer is 2:97.5:0.3:0.

2.

10. A process for preparing a fluorite crystal impurity leachate based on microbial metabolites according to any one of claims 1-9, characterized in that, The preparation process of the fluorite crystal impurity leachate based on microbial metabolites includes the following steps: mixing and stirring the microbial metabolic fermentation broth and deionized water, adding chelating solution and stirring, adding synergistic solution and stirring, adding modified glucosamine magnesium phosphate microsphere slurry and stirring, adding modified hydroxyapatite nanosphere slurry and stirring, adding modified hydroxypropyl methylcellulose ether slurry and stirring, to obtain the fluorite crystal impurity leachate based on microbial metabolites.