A method of inhibiting oxidation of pyrite

Abstract

The application discloses a method for inhibiting pyrite oxidation, and belongs to the technical field of metal mine tailing passivation. The method uses mesoporous silica (MSN) loaded with rhodamine B acylhydrazone (RBA) as a filler to fill a passivator formed by gamma-mercaptopropyl trimethoxysilane to inhibit the oxidation of pyrite. The improved pyrite oxidation inhibition effect greatly slows down the oxidation rate of the pyrite. The self-healing ability of the passivator prolongs the time effect of the passivator on the pyrite in terms of oxidation inhibition, and the oxidation sites of the pyrite are marked with fluorescence, which is beneficial to the rapid identification of the oxidation sites of the pyrite and the timely treatment of the oxidation sites of the pyrite, so that the oxidation sites are prevented from expanding and causing environmental pollution.

Description

Technical Field

[0001] This invention belongs to the field of metal mine tailings passivation technology, specifically relating to a method for inhibiting pyrite oxidation. Background Technology

[0002] Pyrite is one of the most common and abundant metal sulfide tailings. In the natural environment, long-term contact between pyrite and air, water, or microorganisms leads to complex water-rock reactions, slowly forming acidic wastewater containing high concentrations of sulfates and heavy metal ions, known as acid mine wastewater (AMD). AMD is one of the most serious environmental pollution problems globally, posing a direct threat to aquatic life and impacting a wider range of ecosystems through the food chain. For example, the migration and accumulation of heavy metals in surface water, groundwater, and soil can lead to significant changes in soil microbial communities and biodiversity loss over time. Therefore, developing passivating agents to inhibit pyrite oxidation is of significant practical and scientific importance for controlling AMD.

[0003] Currently, the main methods for inhibiting pyrite oxidation include neutralization, covering, sterilization, and surface passivation. Covering is limited by the geographical environment of the tailings and cannot achieve long-term effects; sterilization is easily affected by natural environmental climate, such as rain, which can cause it to fail. Among these, surface passivation involves a chemical reaction between a passivating agent and the functional groups on the pyrite surface, forming a dense, inert passivation film. Therefore, the applicability of the passivating agent depends on its ability to react with the functional groups on the pyrite surface, and the duration of the passivation film's effectiveness directly determines the duration of its ability to inhibit pyrite oxidation. The longer the passivation film remains in place, the better its inhibitory effect on pyrite oxidation.

[0004] In natural environments, with the continuous contact and corrosion of oxidizing media, even if the passivation film can play a passivation role for a long time, it will still be gradually consumed until it fails. At this time, it is necessary to treat the oxidation sites in a timely and rapid manner to prevent the tailings from being continuously oxidized and causing the oxidation situation to expand further.

[0005] Therefore, it is necessary to provide a method for inhibiting pyrite oxidation, extending the effective time of passivating agents suitable for inhibiting pyrite oxidation, and marking pyrite oxidation sites. By increasing the duration of passivating agent effectiveness and achieving rapid location of oxidation sites through the use of passivating agents, it is beneficial to treat oxidation sites in a timely and rapid manner, thereby preventing the tailings from continuously undergoing oxidation, which could lead to further expansion of oxidation and cause AMD (Advanced Melting Point) pollution. Summary of the Invention

[0006] To overcome the problems in the prior art, this invention proposes a method for inhibiting pyrite oxidation. This method involves using mesoporous silica (MSN) loaded with rhodamine B acylhydrazone (RBA) and filled with γ-mercaptopropyltrimethoxysilane (PropS-SH) passivating agent. This passivating agent reacts chemically with the functional groups on the pyrite surface to form a passivation film. This passivation film possesses self-repairing and oxidation corrosion site marking functions, thereby enhancing the sustained inhibition of pyrite oxidation corrosion. Simultaneously, it facilitates the rapid identification of oxidation corrosion sites, enabling timely treatment of these sites and preventing further expansion of oxidation corrosion.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] The method for inhibiting pyrite oxidation is as follows: mesoporous silica loaded with rhodamine B hydrazone is filled with γ-mercaptopropyltrimethoxysilane passivating agent, and a passivation film is formed by the chemical reaction between the passivating agent and the functional groups on the surface of pyrite, thereby inhibiting pyrite oxidation.

[0009] Preferably, the method for preparing the passivating agent includes the following steps:

[0010] (1) Add γ-mercaptopropyltrimethoxysilane to the mixed solution at a volume ratio of 1:19, wherein the mixed solution is obtained by mixing water and ethanol at a volume ratio of 1:5 to 1:8, adjust the pH to 4 to 5, stir to carry out hydrolysis reaction, and obtain silanol solution.

[0011] (2) Under ultrasonic conditions, the nanofiller is added to the silanol solution prepared in step (1) at a ratio of 0.8 to 3.2 g / L and mixed evenly to obtain a passivating agent.

[0012] Preferably, the volume fraction of γ-mercaptopropyltrimethoxysilane in the silanol solution in step (1) is 5%.

[0013] Preferably, in step (1), hydrochloric acid is used to adjust the pH to 4-5, the hydrolysis reaction time is 1-1.5 h, and the reaction temperature is 38-42 °C.

[0014] Preferably, the ultrasonic treatment time in step (2) is 30 min.

[0015] Preferably, in step (b), the nanofiller is MSN@RBA, and the specific preparation method is as follows:

[0016] (2.1) Dissolve hexadecyltrimethylammonium bromide in a mixed solution of ethanol and water at a ratio of 2 g / L, add ethyl silicate (TEOS) at a ratio of 12.5 ml / L and stir, then add ammonia at a ratio of 12.3 ml / L and stir again. After the reaction is complete, wash and dry the product.

[0017] (2.2) The product obtained in step (2.1) is added to a mixed solution of concentrated hydrochloric acid and ethanol at a ratio of 20-30 g / L and refluxed. After washing and drying, the product is calcined in a muffle furnace. The calcined product is then sealed and stored for later use.

[0018] (2.3) The product obtained in step (2.2) and rhodamine B acylhydrazone were added to a mixed solution of water and acetonitrile at a mass ratio of 3:1 to 4:1. After ultrasonic dissolution, the mixed solution was placed in a water bath and stirred. After centrifugation and washing, it was placed in an oven and dried to obtain mesoporous silica nanofiller loaded with rhodamine B acylhydrazone.

[0019] Preferably, the washing in steps (2.1) to (2.3) is as follows: the product is washed with deionized water and ethanol alternately, and each product is washed with deionized water and ethanol three times.

[0020] Preferably, in step (2.1), the volume ratio of ethanol to water in the mixed solution is 5:11.

[0021] In step (2.2), the volume ratio of concentrated hydrochloric acid to ethanol in the mixed solution is 1:30.

[0022] In step (2.3), the volume ratio of water to acetonitrile in the mixed solution is 1:1 to 2:1.

[0023] Preferably, the reflux temperature in step (2.2) is 80-85°C and the reflux time is 10-12h.

[0024] Preferably, the calcination temperature in step (2.2) is 540–550°C and the calcination time is 4–5 h.

[0025] The beneficial effects of this invention are:

[0026] 1. This invention uses PropS-SH / MSN@RBA passivating agent to chemically react with the functional groups on the surface of pyrite to form a passivation film, thereby inhibiting the oxidation of pyrite and reducing the pollution caused by pyrite oxidation to the environment.

[0027] 2. The passivating agent prepared by this invention, when loaded with RBA in MSN, can be actively released from the damaged passivation film site after the passivation film is formed, repairing the micropores or cracks in the passivation film and improving the duration of the passivation film's inhibitory effect on pyrite oxidation.

[0028] 3. The passivating agent prepared by this invention can release RBA to repair the damaged passivation film, and at the same time, it can fluorescently label the oxidation sites, which facilitates rapid location of the oxidation sites and timely treatment. Attached Figure Description

[0029] Figure 1 This is the N2 adsorption-desorption isotherm for MSN.

[0030] Figure 2 Thermogravimetric curves for MSN, RBA, and MSN@RBA.

[0031] Figure 3 The infrared spectrum of the passivating agent prepared in Example 1 is shown.

[0032] Figure 4 The image shows the EIS diagrams of the passivating agents prepared in Examples 1-4.

[0033] Figure 5 Comparative Example 1, Comparative Example 2, Comparative Example 3, Total iron concentration of leachate from 60-day leaching experiment of pyrite sample in Example 1.

[0034] Figure 6 SO4 content of the leachate from pyrite samples in Comparative Examples 1, 2, and 3 (60-day leaching experiment) of Example 1. 2- concentration.

[0035] Figure 7 The static water contact angles of pyrite samples from Comparative Examples 1, 2, and 3, and Example 1;

[0036] Figure 8 The fluorescence state of pyrite samples from Example 1 and Comparative Example 4 after being scratched and immersed in a solution at pH=2 for 24 hours;

[0037] Figure 9 The results show the changes in impedance values ​​of pyrite samples from Comparative Example 2, Comparative Example 3, and Example 1 over time after scratching. Detailed Implementation

[0038] The present invention will be further described in detail below with reference to specific embodiments.

[0039] Unless otherwise specified, all reagents used in the embodiments and comparative examples of this invention are of commercially available analytical grade.

[0040] Example 1

[0041] In this embodiment, the PropS-SH / MSN@RBA passivating agent was prepared using the following method:

[0042] (1) Dissolve hexadecyltrimethylammonium bromide in a mixed solution of ethanol and water at a ratio of 2 g / L (V ethanol: V water = 5:11), add TEOS at a ratio of 12.5 ml / L and stir for 10 min, then add ammonia at a ratio of 12.3 ml / L and stir for 3 h. Wash the product three times with deionized water and ethanol respectively, and then dry.

[0043] (2) The product obtained in (1) was added to a mixed solution of concentrated hydrochloric acid and ethanol at a ratio of 20 g / L (V concentrated hydrochloric acid: V ethanol = 1:30), refluxed in a water bath at 80°C for 10 h, and the product was washed three times with deionized water and ethanol respectively, dried, and then calcined in a muffle furnace at 540°C for 4 h, and then sealed and stored for later use.

[0044] (3) The product obtained in (2) and rhodamine B acylhydrazone were added to a mixed solution of water and acetonitrile (V water:V acetonitrile = 2:1) at a mass ratio of 4:1. The solution was sonicated for 10 min to mix evenly and then placed in a water bath and stirred for 48 h. After centrifugation and washing, the solution was placed in an oven and dried for 12 h to obtain MSN@RBA nanofiller.

[0045] (4) Add γ-mercaptopropyltrimethoxysilane to the mixed solution at a volume ratio of 1:19. The mixed solution is obtained by mixing water and ethanol at a volume ratio of 1:8. Adjust the pH to 4 with 0.5 mol / L hydrochloric acid and stir at 40°C for 1 h to obtain a silanol solution.

[0046] (5) Add MSN@RBA nanofiller to the silanol solution obtained in (4) at a ratio of 2.4 g / L, and sonicate for 30 min to obtain passivating agent.

[0047] In this embodiment, the pH of the passivating agent was adjusted to 9 using 0.5 mol / L ammonia water, and then pyrite powder was added to the passivating agent. The mixture was stirred at 50°C for 2 hours and then dried at 90°C for 24 hours to obtain a pyrite sample with a passivation film, which was designated as 2.4 g / L-PSMR passivated ore.

[0048] Example 2

[0049] In this embodiment, the PropS-SH / MSN@RBA passivating agent was prepared using the following method:

[0050] (1) Dissolve hexadecyltrimethylammonium bromide in a mixed solution of ethanol and water at a ratio of 2 g / L (V ethanol: V water = 5:11), add TEOS at a ratio of 12.5 ml / L and stir for 10 min, then add ammonia at a ratio of 12.3 ml / L and stir for 3 h. Wash the product three times with deionized water and ethanol respectively, and then dry.

[0051] (2) The product obtained in (1) was added to a solution of concentrated hydrochloric acid and ethanol (V concentrated hydrochloric acid: V ethanol = 1:30) at a ratio of 25 g / L. The solution was refluxed in a water bath at 82°C for 11 h. The product was washed three times with deionized water and ethanol respectively, dried, and then calcined in a muffle furnace at 545°C for 4.5 h. The product was then sealed and stored for later use.

[0052] (3) The product obtained in (2) and rhodamine B acylhydrazone were added to a mixed solution of water and acetonitrile (V water:V acetonitrile = 1.5:1) at a mass ratio of 3.5:1. The solution was sonicated for 10 min to mix it evenly, and then stirred in a water bath for 48 h. After centrifugation and washing, the solution was placed in an oven and dried for 12 h to obtain MSN@RBA nanofiller.

[0053] (4) Add γ-mercaptopropyltrimethoxysilane to the mixed solution at a volume ratio of 1:19. The mixed solution is obtained by mixing water and ethanol at a volume ratio of 1:6. Adjust the pH to 5 with 0.5 mol / L hydrochloric acid and stir at 38°C for 1.2 h to obtain a silanol solution.

[0054] (5) Add MSN@RBA nanofiller to the silanol solution obtained in (4) at a ratio of 0.8 g / L, and sonicate for 30 min to obtain passivating agent.

[0055] In this embodiment, the pyrite sample with a passivation film was obtained by the same treatment method as in Example 1, and was designated as 0.8 g / L-PSMR passivated ore.

[0056] Example 3

[0057] In this embodiment, the PropS-SH / MSN@RBA passivating agent was prepared using the following method:

[0058] (1) Dissolve hexadecyltrimethylammonium bromide in a mixed solution of ethanol and water at a ratio of 2 g / L (V ethanol: V water = 5:11), add TEOS at a ratio of 12.5 ml / L and stir for 10 min, then add ammonia at a ratio of 12.3 ml / L and stir for 3 h. Wash the product three times with deionized water and ethanol respectively, and then dry.

[0059] (2) Add the product obtained in (1) to a concentrated hydrochloric acid / ethanol solution (V concentrated hydrochloric acid: V ethanol = 1:30) at a concentration of 30 g / L, reflux in an 85°C water bath for 12 h, wash the product three times with deionized water and ethanol respectively, dry it, and then calcine it in a muffle furnace at 550°C for 5 h, and then seal it for later use.

[0060] (3) The product obtained in (2) and rhodamine B acylhydrazone were added to a mixed solution of water and acetonitrile (V water:V acetonitrile = 1:1) at a mass ratio of 3:1. The solution was sonicated for 10 min to mix it evenly, and then stirred in a water bath for 48 h. After centrifugation and washing, the solution was placed in an oven and dried for 12 h to obtain MSN@RBA nanofiller.

[0061] (4) Add γ-mercaptopropyltrimethoxysilane to the mixed solution at a volume ratio of 1:19. The mixed solution is obtained by mixing water and ethanol at a volume ratio of 1:5. Adjust the pH to 4.5 with 0.5 mol / L hydrochloric acid and stir at 42°C for 1.5 h to obtain a silanol solution.

[0062] (5) Add MSN@RBA nanofiller to the silanol solution obtained in (4) at a ratio of 1.6 g / L, and sonicate for 30 min to obtain passivating agent.

[0063] In this embodiment, the same processing method as in Example 1 was used to obtain a pyrite sample with a passivation film, which was designated as 1.6 g / L-PSMR passivated ore.

[0064] Example 4

[0065] In this embodiment, the PropS-SH / MSN@RBA passivating agent was prepared using the same method as in Example 1. The difference is that the MSN@RBA nanofiller was added at a ratio of 3.2 g / L in this embodiment.

[0066] In this embodiment, the same processing method as in Example 1 was used to obtain a pyrite sample with a passivation film, which was designated as 3.2 g / L-PSMR passivated ore.

[0067] Comparative Example 1

[0068] This comparative example uses raw pyrite ore samples without a passivation film for the experiment.

[0069] Comparative Example 2

[0070] This comparative example uses the same method as Example 1 to prepare the PropS-SH passivating agent.

[0071] This comparative example uses the same processing method as Example 1 to obtain a pyrite sample with a passivation film, denoted as PropS-SH passivated ore.

[0072] Comparative Example 3

[0073] This comparative example uses the same method as Example 1 to prepare the PropS-SH / MSN passivating agent.

[0074] This comparative example uses the same processing method as Example 1 to obtain a pyrite sample with a passivation film, denoted as PropS-SH / MSN passivated ore.

[0075] Comparative Example 4

[0076] This comparative example uses the same method as Example 1 to prepare the PropS-SH / RBA passivating agent.

[0077] This comparative example uses the same processing method as Example 1 to obtain a pyrite sample with a passivation film, denoted as PropS-SH / RBA passivated ore.

[0078] The MSN prepared in Example 1 was analyzed using BET testing, and its specific surface area was found to be 1330.49 m². 2 / g, pore volume is 0.83cm 3 / g, proving that MSN can be used as an RBA carrier.

[0079] Thermogravimetric analysis was performed on the MSN@RBA nanofiller prepared in Example 1, and the results are as follows: Figure 2 As shown, by Figure 2 It can be seen that MSN has no significant mass loss; the weight loss of MSN@RBA is divided into two stages. The mass loss before 300℃ is caused by water evaporation, and the mass loss between 300℃ and 500℃ is caused by the loaded RBA, proving that the RBA was successfully loaded in MSN and the loading amount was 11.20%.

[0080] The chemical composition of the passivating agents in Examples 2-4 was analyzed using infrared spectroscopy, and the results were similar to those in Example 1. Figure 3 It can be seen that at 2929cm -1 2553cm -1 1245cm -1 Stretching vibration peaks of CH, SH, and Si-C appear at 919 cm⁻¹. -1 688cm -1 The presence of a stretching vibration peak belonging to the Fe-O bond in the Fe-O-Si bond indicates that the organosilane, after hydrolysis, is coated on the mineral surface with Fe-O-Si bonds.

[0081] Electrochemical impedance spectroscopy (EIS) was performed on the pyrite electrodes used in Comparative Examples 1, 2, and Examples 1-4. A three-electrode system was used: a pyrite electrode, a platinum foil electrode (10 mm × 10 mm), and a saturated calomel electrode (SCE) as the working electrode, counter electrode, and reference electrode, respectively. Na₂SO₄ at pH 2 and a concentration of 0.2 mol / L was used as the electrolyte. EIS measurements were performed with the open-circuit potential (OCP) as the starting voltage. The results are as follows: Figure 4 As shown. Generally, the larger the curve radius in the Nyquist fitting plot, the higher the R² of the fitted graph. ct and R f The larger the value, the better the passivation effect.

[0082] pass Figure 4 It can be seen that the curve radii of Examples 1-4 are all larger than those of Comparative Examples 1 and 2, proving that the passivating agent in Examples 1-4 has a better effect on inhibiting the oxidation of pyrite. MSN@RBA has hydroxyl groups on its surface, which can act as a "filler" to crosslink with PropS-SH to fill microcracks in the passivation film and enhance the diffusion shielding ability of the coating. Meanwhile, compared with Example 1, the oxidation inhibition effect on pyrite in Example 4 begins to decrease. This is because when too much MSN@RBA nanofiller is added, the viscosity of silane decreases during the formation of the passivation film, resulting in poor coating integrity of pyrite and a decrease in its oxidation inhibition effect. Therefore, controlling the amount of MSN@RBA nanofiller added is also beneficial to improving the oxidation inhibition effect on pyrite.

[0083] Pyrite samples from Examples 1 and Comparative Examples 1-3 were added to 100 mL of hydrochloric acid solution with pH = 1 and reacted for 60 days. The total iron concentration in the leachate was obtained as follows: Figure 5 As shown, SO4 2- Concentration such as Figure 6 As shown, Figure 5 , 6 The PropS-SH / MSN@RBA passivated ore corresponds to the sample in Example 1, the PropS-SH passivated ore corresponds to the sample in Example 2, and the PS / MSN passivated ore corresponds to the sample in Example 3.

[0084] pass Figure 5 , Figure 6 It can be seen that, compared with Comparative Examples 1-3, the passivating agent in Example 1 has a better effect on inhibiting the oxidation of pyrite. This is because the RBA loaded in the nanocontainer can be released under extremely acidic conditions to repair the micropores or cracks in the coating, thereby achieving long-term protection of pyrite.

[0085] The static water capsular angles of pyrite samples from Examples 1 and 1-3 were measured, and the results are as follows: Figure 7As shown in the figure, A corresponds to sample 1, B corresponds to sample 2, C corresponds to sample 3, and D corresponds to sample 1 of Example 1.

[0086] pass Figure 7 It can be seen that the pyrite sample treated with the passivating agent in Example 1 has the largest static water antenna angle, reaching 90.52°, indicating that the pyrite sample treated with the passivating agent in Example 1 has high hydrophobicity, which is beneficial to inhibiting the oxidation effect of water on pyrite.

[0087] X-shaped scratches were made on the surface of the pyrite samples of Example 1 and Comparative Example 4 with a blade. The pyrite samples were then immersed in a Na2SO4 solution with pH=2 for 24 hours. The samples were then observed and photographed using a fluorescence microscope. The results are shown in Figure 8.

[0088] pass Figure 8 It can be seen that the pyrite sample in Example 1 has more obvious fluorescence luminescence properties. This is because after MSN loads RBA, MSN to a certain extent protects RBA, reduces environmental interference to RBA, and increases the fluorescence signal intensity in the corroded area.

[0089] X-shaped scratches were made on the surface of the pyrite samples from Examples 1, 2, and 3 using a blade. The pyrite samples were then immersed in a Na₂SO₄ solution at pH 2. The impedance changes on the passivation film surface were periodically monitored using a CHI 660e electrochemical workstation. The results are as follows: Figure 9 As shown.

[0090] pass Figure 9 It can be seen that, compared with Comparative Examples 2 and 3, the radius of the Nyquist plot curve of Example 1 first decreases and then tends to stabilize, indicating that R f The impedance gradually stabilized after decreasing. Meanwhile, the impedance of the pyrite sample in Example 1 was significantly higher than that of Comparative Examples 2 and 3, indicating that the passivating film formed on the pyrite surface by the passivating agent in Example 1 possesses a certain self-healing function. This is mainly because the release of rhodamine B hydrazone from the nanofiller inhibited the oxidation at the pyrite scratches.

[0091] In summary, by using the passivating agent of this invention to inhibit pyrite oxidation, the oxidation inhibition effect of the passivating agent after forming a passivation film on pyrite can be effectively utilized. At the same time, the self-healing ability prolongs the time of the passivating agent's effect on inhibiting pyrite oxidation. It can also achieve fluorescent labeling of pyrite oxidation sites to facilitate rapid detection of pyrite oxidation sites. After the passivation film fails, the oxidation sites can be treated in a timely manner to prevent further expansion of pyrite oxidation sites.

[0092] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for inhibiting the oxidation of pyrite, characterized in that: The method for inhibiting pyrite oxidation is as follows: mesoporous silica loaded with rhodamine B hydrazone is filled with γ-mercaptopropyltrimethoxysilane passivating agent, and a passivation film is formed by the chemical reaction between the passivating agent and the functional groups on the surface of pyrite, thereby inhibiting pyrite oxidation.

2. The method for inhibiting pyrite oxidation according to claim 1, characterized in that: The method for preparing the passivating agent includes the following steps: (1) Add γ-mercaptopropyltrimethoxysilane to the mixed solution at a volume ratio of 1:19, wherein the mixed solution is obtained by mixing water and ethanol at a volume ratio of 1:5 to 1:8, adjust the pH to 4 to 5, stir to carry out hydrolysis reaction, and obtain silanol solution. (2) Under ultrasonic conditions, the nanofiller is added to the silanol solution prepared in step (1) at a ratio of 0.8~3.2 g / L and mixed evenly to obtain a passivating agent.

3. The method for inhibiting pyrite oxidation according to claim 2, characterized in that: In step (1), the volume fraction of γ-mercaptopropyltrimethoxysilane in the silanol solution is 5%.

4. The method for inhibiting pyrite oxidation according to claim 2, characterized in that: In step (1), hydrochloric acid is used to adjust the pH to 4-5, the hydrolysis reaction time is 1-1.5 h, and the reaction temperature is 38-42 °C.

5. The method for inhibiting pyrite oxidation according to claim 2, characterized in that: The ultrasonic treatment time in step (2) is 30 minutes.

6. The method for inhibiting pyrite oxidation according to claim 2, characterized in that, In step (2), the nanofiller is MSN@RBA, and the specific preparation method is as follows: (2.1) Dissolve hexadecyltrimethylammonium bromide in a mixed solution of ethanol and water at a ratio of 2 g / L, add ethyl silicate at a ratio of 12.5 ml / L and stir, then add ammonia at a ratio of 12.3 ml / L and stir again. After the reaction is complete, wash and dry the product. (2.2) The product obtained in step (2.1) is added to a mixed solution of concentrated hydrochloric acid and ethanol at a ratio of 20~30 g / L and refluxed. After washing and drying, the product is calcined in a muffle furnace. The calcined product is then sealed and stored for later use. (2.3) The product obtained in step (2.2) and rhodamine B acylhydrazone were added to a mixed solution of water and acetonitrile at a mass ratio of 3:1 to 4:

1. After ultrasonic dissolution, the mixed solution was placed in a water bath and stirred. After centrifugation and washing, it was placed in an oven and dried to obtain mesoporous silica nanofiller loaded with rhodamine B acylhydrazone.

7. The method for inhibiting pyrite oxidation according to claim 6, characterized in that: The washing process in steps (2.1) to (2.3) involves washing the product with deionized water and ethanol alternately, with each washing three times.

8. The method for inhibiting pyrite oxidation according to claim 6, characterized in that: In step (2.1), the volume ratio of ethanol to water in the mixed solution is 5:

11. In step (2.2), the volume ratio of concentrated hydrochloric acid to ethanol in the mixed solution is 1:

30. In step (2.3), the volume ratio of water to acetonitrile in the mixed solution is 1:1 to 2:

1.

9. The method for inhibiting pyrite oxidation according to claim 6, characterized in that: In step (2.2), the reflux temperature is 80~85℃ and the reflux time is 10~12h.

10. The method for inhibiting pyrite oxidation according to claim 6, characterized in that: In step (2.2), the calcination temperature is 540~550℃ and the calcination time is 4~5h.

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