Preparation method and application of water-resistant high-activity modified manganese ore for remediation of antibiotic-contaminated soil

Abstract

The application discloses a preparation method and application of a water-resistant high-activity modified manganese ore for repairing antibiotic contaminated soil, relates to the technical field of soil pollution repair, and comprises a preparation step of base manganese ore C and a humic acid-ferrous iron composite modification step; (1) the base manganese ore C is prepared by using an acid-alkali step-by-step coprecipitation method; and (2) the humic acid-ferrous iron composite modification step is carried out under anaerobic conditions. The preparation method and application of the water-resistant high-activity modified manganese ore for repairing antibiotic contaminated soil have the advantages that the base manganese ore is prepared by using an acid-alkali step-by-step coprecipitation method, the content of Mn(III) is directionally increased, after being combined with the humic acid-ferrous iron composite modification, the content of Mn(III) is doubled, a large amount of hydroxyl radicals are generated, and the double degradation paths greatly improve the antibiotic degradation capacity.

Description

Technical Field

[0001] This invention relates to the field of soil pollution remediation technology, specifically to a method for preparing and applying water-resistant, highly active modified manganese ore for the remediation of antibiotic-contaminated soil. Background Technology

[0002] With the rapid development of the medical, animal husbandry, and agricultural industries, various antibiotics are used extensively, and residual antibiotics and their transformation products continuously enter the soil environment, becoming a global soil pollution problem. Residual antibiotics in soil disrupt the food web composed of soil microorganisms and invertebrates, disturb the soil's ecological structure and biogeochemical cycles, and reduce soil productivity. Furthermore, most antibiotics have stable molecular structures and strong environmental persistence, making them difficult to degrade under natural conditions, posing high ecological and health risks. Therefore, developing remediation technologies for antibiotic-contaminated soil is an urgent need for the current treatment of new pollutants.

[0003] Natural manganese minerals possess a large specific surface area and strong oxidizing capacity, enabling them to degrade organic pollutants without the need for additional oxidants, light, or heat. They are green and low-cost soil remediation materials, and have been proven to effectively degrade phenols, polycyclic aromatic hydrocarbons, antibiotics, and other organic pollutants. Existing research indicates that the oxidizing activity of manganese in different valence states varies. Trivalent manganese (Mn(III)) exhibits significantly better degradation effects on organic pollutants than tetravalent manganese (Mn(IV)). However, conventionally prepared manganese minerals are predominantly Mn(IV) with low Mn(III) content, thus limiting their oxidizing activity.

[0004] Furthermore, soil moisture is a key factor limiting the remediation efficacy of manganese ore: in low-moisture environments, manganese ore can rapidly degrade antibiotics, while in high-moisture soils and soil-water suspension systems, water molecules occupy the active sites of manganese ore, significantly inhibiting antibiotic degradation reactions. Ordinary manganese ore has poor water resistance and cannot be adapted to remediation scenarios of soils with different moisture contents, especially high-moisture-content contaminated soils. Therefore, we propose a method for preparing water-resistant, highly active modified manganese ore for the remediation of antibiotic-contaminated soils and its application. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing water-resistant, highly active modified manganese ore for the remediation of antibiotic-contaminated soil and its application, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing water-resistant and highly active modified manganese ore for remediation of antibiotic-contaminated soil, comprising a preparation step of basic manganese ore C and a fulvic acid-ferrous composite modification step; (1) The basic manganese ore C was prepared by a stepwise acid-base co-precipitation method, specifically as follows: A 0.143 mol / L potassium permanganate solution and a 0.143 mol / L manganese sulfate monohydrate solution were mixed in ultrapure water and stirred for 10 min to obtain a mixed solution. Add 10% nitric acid by mass to the mixture and react at a constant temperature of 70℃ for 120 min; Add sodium hydroxide to the reaction system and stir for 10 min to form a solid precipitate; Collect the solid phase by cooling, centrifugation, or filtration, and wash with deionized water until the conductivity of the eluent is ≤20 μS. cm -1 Dry, grind, and pass through a 100-mesh sieve to obtain basic manganese ore C; (2) The fulvic acid-ferrous composite modification step is carried out under anaerobic conditions, specifically as follows: Take 5g of the aforementioned basic manganese ore C, add it to 1L of deoxygenated ultrapure water, and place it in an anaerobic environment; Add 12.33g of fulvic acid and stir to mix well; Add ferrous chloride, seal and protect from light, and shake at 180 r / min for 1 h; The solid phase was collected by centrifugation and then anaerobically dried to obtain modified manganese ore.

[0007] Preferably, the volume of nitric acid added in step (1) is 15 mL; the amount of sodium hydroxide added in step (1) is 0.0125 mol.

[0008] Preferably, the amount of ferrous chloride added in step (2) is 126.75g, and modified manganese ore CFe(II)O3 is prepared.

[0009] Preferably, the amount of ferrous chloride added in step (2) is 26.33g or 63.38g, respectively, to prepare modified manganese ore CFe(II)01 and CFe(II)02.

[0010] The application of a water-resistant, highly active modified manganese ore for the remediation of antibiotic-contaminated soil, wherein the modified manganese ore is prepared by the manganese ore preparation method according to any one of claims 1 to 4.

[0011] Preferably, the antibiotic is any one or more of sulfamethoxazole, sulfadiazine, penicillin, cefotaxime, and thiamphenicol.

[0012] Preferred application methods include: 1) Air dry and grind the soil to be repaired, pass it through a 60-mesh sieve, and adjust the soil moisture content to 5%~200%; 2) Add the modified manganese ore at a ratio of 1.25% of the soil mass and mix thoroughly; 3) Soil remediation was completed after 7 days of constant temperature incubation in the dark.

[0013] Preferably, the modified manganese ore is the modified manganese ore CFe(II)O3 prepared according to claim 3.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention relates to a method for preparing and applying a water-resistant, highly active modified manganese ore for the remediation of antibiotic-contaminated soil. The method employs a stepwise acid-base co-precipitation process to prepare the basic manganese ore, which directionally increases the Mn(III) content. Combined with fulvic acid-ferrous composite modification, the Mn(III) content doubles, while simultaneously generating a large number of hydroxyl radicals. This dual degradation pathway significantly enhances the antibiotic degradation capacity. The prepared manganese ore exhibits strong hydrophobicity, making it suitable for soils with varying moisture content, and demonstrates high water resistance in its degradation activity. It shows highly efficient degradation of five common antibiotics: sulfamethoxazole, sulfadiazine, penicillin, cefotaxime, and thiamphenicol, making it applicable to antibiotic-contaminated soils from livestock, agriculture, and medical sources. In soils with varying moisture content, the final residual rate of various antibiotics is stably controlled at 20%-28%, demonstrating excellent remediation effects. Attached Figure Description

[0015] Figure 1 X-ray diffraction spectra of the three manganese ores prepared in this invention; Figure 2 The water vapor adsorption isotherms of the three manganese ores prepared in this invention at 298.15 K; Figure 3 The water contact angles of the three types of manganese ores prepared in this invention; Figure 4 X-ray photoelectron spectra of the three manganese ores prepared in this invention; Figure 5 The superoxide radical signals of the three types of manganese ores prepared in this invention; Figure 6 The degradation effect of sulfamethoxazole on three types of manganese ore at different moisture contents is shown in the figure. Figure 7 The degradation effects of three types of manganese ore on different antibiotics at moisture contents of 30% and 100% are shown in the figure. Figure 8 The degradation effect of manganese ore C modified with different concentrations of ferrous Fe(II) on sulfamethoxazole is shown in the figure. Figure 9 The degradation effect of different manganese ores modified with ferrous Fe(II) on sulfamethoxazole is shown in the figure. Figure 10 The content of Mn(III) and ·OH free radicals at the interface of manganese ore C modified with ferrous Fe(II); Figure 11 The degradation effect of different amounts of manganese ore CFe(II)O3 on sulfamethoxazole in soil is shown in the figure. Figure 12 The graph shows the degradation effect of 1.25% CFe(II)O3 on sulfamethoxazole in soils with different moisture contents. Figure 13 The degradation effect of 1.25% CFe(II)O3 on different antibiotics in soil is shown in the figure. Figure 14 This is a process flow diagram for the present invention. Detailed Implementation

[0016] 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, and 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.

[0017] In the embodiments of the present invention, manganese ore A is manganese ore prepared by organic reduction precipitation method of (NH4)2C2O4·H2O and KMnO4; manganese ore B is manganese ore prepared by alkaline coprecipitation method of MnCl2, NaOH, and KMnO4; and manganese ore C is manganese ore synthesized by stepwise acid-base coprecipitation method of KMnO4, MnSO4·H2O, HNO3, and NaOH. Manganese ore CFe(II)O1, manganese ore CFe(II)O2, and manganese ore CFe(II)O3 are prepared by mixing 5 g of manganese ore C with 12.33 g of fulvic acid with 26.33 g, 63.38 g, and 126.75 g of FeCl2, respectively.

[0018] Example 1 Preparation and characterization of potassium manganese ore: like Figure 14 As shown, the present invention first involves a manganese ore preparation process, the specific preparation process of which is as follows: Preparation of manganese ore: Manganese ore A was synthesized using an organic reduction precipitation method: A mixed solution (130 mL) of (NH4)2C2O4·H2O and KMnO4 was prepared at reduction / oxidation equivalences of 0.0217 M and 0.0487 M. The solution was hydrothermally stirred at 90 °C for 10 h, utilizing the reduction of Mn(VII) by oxalate to drive homogeneous nucleation of Mn(IV) oxides. After cooling the reaction solution to room temperature, the solid product was recovered by centrifugation or filtration, and the eluent was washed repeatedly with deionized water until the conductivity of the eluent decreased to 20 μS·cm. -1 The product was then dried, ground, and passed through a 100-mesh standard sieve before being stored in a desiccator.

[0019] Manganese ore B was synthesized using an alkaline coprecipitation method: 0.3 M MnCl2 (125 mL) and 0.5 M NaOH (250 mL) were premixed at room temperature, and 0.2 M KMnO4 (125 mL) was added dropwise. The Mn(IV) coprecipitate was generated in situ through the disproportionation reaction of Mn(II) and Mn(VII) in the alkaline medium. After stirring the suspension for 30 min, it was aged at 60 ℃ for 12 h to promote the ordering of the layered structure. After cooling the reaction solution to room temperature, the solid product was recovered by centrifugation or filtration, and the eluent was washed repeatedly with deionized water until the conductivity of the eluent decreased to 20 μS·cm. - ¹ The product is dried and ground, then passed through a 100-mesh standard sieve and stored in a desiccator.

[0020] Mineral C was synthesized using a stepwise acid-base coprecipitation method: 0.143 M KMnO4 and 0.143 M MnSO4·H2O were co-dissolved in 70 mL of ultrapure water, premixed for 10 min, and then 15 mL of 10% HNO3 was added dropwise. The reaction was carried out at 70 °C for 120 min to achieve the directional oxidation of Mn(II) to Mn(III) in an acidic medium. Subsequently, 0.0125 mol NaOH was added for alkalization, and the mixture was stirred for 10 min to induce the hydrolysis-condensation precipitation of Mn(III). After cooling the solution to room temperature, the solid product was recovered by centrifugation or filtration and washed repeatedly with deionized water until the conductivity of the eluent decreased to 20 μS·cm. -1 The product was then dried, ground, and passed through a 100-mesh standard sieve before being stored in a desiccator.

[0021] Modification of manganese ore: Active manganese minerals were selected as the modification targets. 5 g of manganese ore was weighed into 1 L of air-free ultrapure water. 12.33 g of fulvic acid was added to the solution in an anaerobic incubator, followed by the addition of 6.33 g, 63.38 g, and 126.75 g of FeCl2, respectively, designated as manganese ore Fe(II)O1, Fe(II)O2, and Fe(II)O3. The bottle opening was sealed with sealing film to prevent O2 entry. The sample was shaken at 180 rpm for 1 h in the dark. After centrifugation, it was air-dried in an anaerobic incubator and stored for later use.

[0022] Characterization of modified manganese ore: The X-ray diffractometer of this patent was used to identify the phase composition of three types of manganese ore. Figure 1 The diffraction peaks of the (001), (002), and (111) crystal planes of naphthoore were observed. All three manganese minerals prepared belong to naphthoore, which is a common manganese mineral in soil. Meanwhile, the 001 peak gradually weakened from manganese ore A, manganese ore B to manganese ore C, while the proportion of the 111 peak gradually increased. Manganese ore C showed that the 111 peak was dominant.

[0023] The water vapor adsorption isotherms of three manganese ores were determined using a fully automated specific surface area and porosity analyzer. Figure 2 The vertical axis represents the number of water molecules per unit specific surface area. Under different pressures, manganese ore C has a lower number of surface water molecules than manganese ore A and manganese ore B, exhibiting greater hydrophobicity.

[0024] The water contact angle of three types of manganese ore was measured using a contact angle measuring instrument. Figure 3 The water contact angles of manganese ore A, manganese ore B, and manganese ore C are 18°, 33°, and 38°, respectively, further confirming that manganese ore C has high hydrophobicity.

[0025] The contents of Mn(Ⅳ), Mn(Ⅲ) and Mn(Ⅱ) in three types of manganese ores were analyzed by X-ray photoelectron spectroscopy.

[0026] Figure 4 The Mn(III) content in manganese ore C is 38%, higher than that in manganese ore A and manganese ore B (31% and 36%, respectively). High Mn(III) content in manganese ore can enhance the oxidative activity of the mineral through lattice defects and oxygen vacancies, thereby improving its ability to oxidize organic pollutants. Furthermore, Mn(III) is more likely than Mn(IV) to form coordinate or covalent bonds with functional groups in pollutant molecules, achieving effective binding. The electron transfer barrier between Mn(III) and pollutants is lower than that of Mn(IV), resulting in a relatively higher reaction rate. Therefore, manganese ore with high Mn(III) content generally exhibits higher oxidative activity.

[0027] Active oxygen free radicals in three types of manganese ores were measured using electron paramagnetic resonance imaging. Figure 5 •O2 was detected in - The signal of free radicals was significantly higher in manganese ore C than in manganese ore A and manganese ore B, indicating that manganese ore C exhibited higher free radical catalytic activity.

[0028] Example 2 Effects of manganese ores with different moisture contents on the degradation of sulfamethoxazole: Manganese ore A, B, and C were dried at 80℃ for 8 hours to obtain manganese ore with a moisture content of nearly 0%. 100 mg of each of the three manganese ores were weighed into 5 mL centrifuge tubes, and the moisture content was controlled by adding water to achieve concentrations of 0%, 15%, 30%, 50%, 100%, and 200% (wt / wt). After shaking for 20 seconds to ensure thorough mixing with the manganese ore, 100 μL of a sulfamethoxazole methanol solution was added to the minerals using a 100 μL microsyringe. The mixture was stored in the dark, where the methanol would evaporate rapidly. After 1 hour of reaction, 2 mL of extraction reagent (0.1% formic acid aqueous solution: acetonitrile = 1:1, V / V) was added, and the mixture was sonicated for 10 min before being filtered through a 0.22 μm organic filter. The filtrate was collected in a liquid chromatography vial. Three parallel experiments were conducted for each group. The concentration of sulfamethoxazole in the filtrate was determined using an Agilent 1260 Infinity II liquid chromatograph. The mobile phase was 0.1% formic acid aqueous solution: methanol = 87:13 (V / V), and the detection wavelength was 265 nm.

[0029] Figure 6 The diagram shows the degradation effects of manganese ore A, manganese ore B, and manganese ore C with different moisture contents on sulfamethoxazole. At 0% moisture content, after 1 hour of reaction, manganese ore A, B, and C all showed good degradation effects on sulfamethoxazole, with residual rates of 55%, 25%, and 12%, respectively. However, with increasing moisture content, the degradation effects of manganese ore A and B on sulfamethoxazole decreased significantly, with residual rates increasing to 85% and 72%, respectively, at 15% moisture content. At 100% moisture content, the degradation of sulfamethoxazole by manganese ore A and B was almost inhibited, with residual rates of 95% and 97%, respectively. Manganese ore C showed significantly stronger water resistance in the degradation of sulfamethoxazole, with residual rates remaining at 22%–25% at moisture contents ranging from 15% to 200%. A slight increase was observed only at 300% moisture content, but it still showed good degradation effects on sulfamethoxazole, with a residual rate of 41%. Therefore, manganese ore C exhibits high degradation effects on sulfamethoxazole at various moisture contents, and its activity has high water resistance.

[0030] Example 3 Degradation effects of manganese ore with high moisture content on different antibiotics: Following the method in Example 2, sulfamethoxazole, sulfadiazine, penicillin, cefotaxime, and thiamphenicol were applied to manganese ore A, manganese ore B, and manganese ore C with moisture contents of 30% and 100%, respectively. After 1 h of reaction, the residual rates of different antibiotics in the filtrate were determined according to the method in Example 2. Figure 7The results showed that the residual rates of different antibiotics in manganese ore A remained at 85%–93% at 30% and 100% moisture content. The residual rates of different antibiotics in manganese ore B remained at 72%–92% at 30% and 100% moisture content. However, the residual rates of different antibiotics in manganese ore C were only 14%–40% at 30% and 100% moisture content. At higher moisture content, manganese ore C showed good degradation effects on all five antibiotics.

[0031] Example 4 Degradation effect of Fe(II) modified manganese ore C on sulfamethoxazole under high moisture content: Sulfamethoxazole was applied to manganese ore C modified with different ferrous concentrations and 30% moisture content according to the method in Example 2. After 30 min and 60 min of reaction, the residual rate of sulfamethoxazole in the filtrate was determined according to the method in Example 2. Figure 8 The results showed that after 30 min of reaction, the residual rates of sulfamethoxazole in manganese ore C, manganese ore CFe(II)01, manganese ore CFe(II)02, and manganese ore CFe(II)03 were 45%, 32%, 30%, and 16%, respectively. After 60 min of reaction, the residual rates of sulfamethoxazole in manganese ore C, manganese ore CFe(II)01, manganese ore CFe(II)02, and manganese ore CFe(II)03 were 25%, 20%, 17%, and 8%, respectively. With increasing Fe(II) loading, the degradation effect of sulfamethoxazole on manganese ore C significantly increased. Example 5 Degradation effect of Fe(II) modified manganese ores on sulfamethoxazole under high moisture content: Sulfamethoxazole was applied to different ferrous modified manganese ores with 30% and 100% moisture content according to the method in Example 2. After 60 min of reaction, the residual rate of sulfamethoxazole in the filtrate was determined according to the method in Example 2. Figure 9 The residual rates of sulfamethoxazole in manganese ore C, manganese ore CFe(II)01, manganese ore CFe(II)02, and manganese ore CFe(II)03 after 30 min of reaction were 45%, 32%, 30%, and 16%, respectively. After 60 min of reaction, the residual rates of sulfamethoxazole in manganese ore C, manganese ore CFe(II)01, manganese ore CFe(II)02, and manganese ore CFe(II)03 were 25%, 20%, 17%, and 8%, respectively. The degradation effect of sulfamethoxazole on manganese ore C significantly increased with increasing Fe(II) loading. The ratios of 5 g manganese ore to 26.33 g, 63.38 g, and 126.75 g FeCl2 for manganese ore CFe(II)01, CFe(II)02, and CFe(II)03 were respectively, with 126.75 g FeCl2 showing the best modification effect on manganese ore.

[0032] Example 6 Determination of Mn(III) and ·OH radicals in manganese ore C and Fe(II) modified manganese ore C: The Mn(III) content in manganese ore was determined by the sodium pyrophosphate colorimetric method. 2 mL of 100 mM sodium pyrophosphate was added to 25 mg of manganese ore, shaken for 10 min, and then filtered through a 0.22 μm aqueous filter. The absorbance was measured at 484 nm using a UV-Vis spectrophotometer (Shimadzu UV-2600, Japan), and the Mn(III) content was calculated. Additionally, 25 μL of 20 mM sodium benzoate and 1 mL of water:methanol (1:1, V / V) extract were added to 25 mg of manganese ore, shaken for 5 min, and then filtered through a 0.22 μm organic filter. The concentration of p-hydroxybenzoic acid, the product of the reaction between sodium benzoate and ·OH, was determined using the liquid chromatography method described in Example 2. The mobile phase was 0.1% trifluoroacetic acid aqueous solution:acetonitrile (75:25, V / V), and the detection wavelength was 255 nm.

[0033] Figure 10 The results showed that the Mn(III) content in manganese ore C and manganese ore CFe(II)O3 was 82 mg / g and 179 mg / g, respectively. No ·OH radicals were detected in manganese ore C, while the ·OH radical content in manganese ore CFe(II)O3 was as high as 210 μM. Mn(III) in manganese ore readily complexes with antibiotics and readily undergoes electron transfer, representing the main non-radical pathway driving antibiotic degradation. ·OH, on the other hand, has oxidative activity and represents the main free radical pathway driving antibiotic degradation.

[0034] Fe(II) plays two main roles in the modification process. First, it reacts with Mn(IV) in manganese ore to produce an active Mn(III) intermediate. Second, Fe(II) induces the formation of ·OH radicals in the system. Third, fulvic acid is added during the modification process. Fulvic acid has reducing properties and can synergistically promote the reduction of Mn(IV) to Mn(III) with Fe(II). Fulvic acid can also participate in the redox cycle of Fe(II) in manganese ore, synergistically promoting the generation of ·OH radicals.

[0035] Example 7 Degradation effects of manganese ore C and Fe(II) modified manganese ore C on sulfamethoxazole in soil: Soil samples were air-dried and ground through a 60-mesh sieve. After drying at 105℃ for 8 hours, the initial moisture content of the air-dried soil samples was determined to be approximately 5%. Moisture was added to the air-dried soil samples to prepare soil samples with a moisture content of 50%. Manganese ore C and manganese ore CFe(II)O3 were added to the soil samples at mass ratios of 0%, 0.25%, 0.75%, and 1.25%, respectively, and the samples were shaken for 30 minutes to complete the application of manganese ore to the soil samples. Sulfamethoxazole-contaminated soil was prepared according to the method in Example 2 and incubated in the dark for 7 days. The residual rate of sulfamethoxazole in the soil was extracted and determined according to the method in Example 2.

[0036] Figure 11 The results showed that the residual rate of sulfamethoxazole in the soil samples gradually decreased with the increase of manganese ore C application. When the manganese ore C application amount was 1.25%, the residual rate of sulfamethoxazole in the soil was 42%. However, the degradation effect of manganese ore CFe(II)O3 was better than that of manganese ore C, and the residual rate of sulfamethoxazole in the soil was 21% when the application amount was 1.25%.

[0037] Example 8 The degradation effect of Fe(II) modified manganese ore C on sulfamethoxazole in soils with different moisture contents: Following the method in Example 7, sulfamethoxazole-contaminated soils with moisture contents of 15%, 30%, 50%, 100%, and 200% were prepared and 1.25% manganese ore CFe(II)O3 was applied. The residual rate of sulfamethoxazole in soils with different moisture contents was extracted and determined according to the method in Example 2.

[0038] Figure 12 The application of 1.25% manganese ore CFe(II)O3 showed that the residual rate of sulfamethoxazole in soil samples with several moisture contents remained between 20% and 28%. Even in soil samples with 200% moisture content, the residual rate of sulfamethoxazole was only 28%. This indicates that the manganese ore used in this invention has a high degradation effect on sulfamethoxazole in soil samples with high moisture content, and the manganese ore used has high activity and water resistance.

[0039] Example 9 The degradation effect of Fe(II) modified manganese ore C on different antibiotics in soils with high moisture content: Following the method in Example 7, soils contaminated with sulfamethoxazole, sulfadiazine, penicillin, cefotaxime, and thiamphenicol with a moisture content of 50% were prepared and 1.25% manganese ore CFe(II)O3 was applied. The residual rates of different antibiotics sulfonium in the soil were extracted and determined according to the method in Example 2.

[0040] Figure 13 The results showed that under the application of 1.25% manganese ore CFe(II)O3, the residue rates of five antibiotics remained at 20%~30%. This indicates that the manganese ore prepared in this invention has high degradation activity for antibiotics in soil samples with high moisture content, and the prepared manganese ore has wide applicability.

[0041] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0042] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A method for preparing water-resistant, highly active modified manganese ore for remediation of antibiotic-contaminated soil, characterized in that, This includes the preparation steps of basic manganese ore C and the fulvic acid-ferrous composite modification steps; (1) The basic manganese ore C was prepared by a stepwise acid-base co-precipitation method, specifically as follows: A 0.143 mol / L potassium permanganate solution and a 0.143 mol / L manganese sulfate monohydrate solution were mixed in ultrapure water and stirred for 10 min to obtain a mixed solution. Add 10% nitric acid by mass to the mixture and react at a constant temperature of 70℃ for 120 min; Add sodium hydroxide to the reaction system and stir for 10 min to form a solid precipitate; Collect the solid phase by cooling, centrifugation, or filtration, and wash with deionized water until the conductivity of the eluent is ≤20 μS. cm -1 Dry, grind, and pass through a 100-mesh sieve to obtain basic manganese ore C; (2) The fulvic acid-ferrous composite modification step is carried out under anaerobic conditions, specifically as follows: Take 5g of the aforementioned basic manganese ore C, add it to 1L of deoxygenated ultrapure water, and place it in an anaerobic environment; Add 12.33g of fulvic acid and stir to mix well; Add ferrous chloride, seal and protect from light, and shake at 180 r / min for 1 h; The solid phase was collected by centrifugation and then anaerobically dried to obtain modified manganese ore.

2. The method for preparing water-resistant, highly active modified manganese ore for remediation of antibiotic-contaminated soil according to claim 1, characterized in that, The volume of nitric acid added in step (1) is 15 mL; the amount of sodium hydroxide added in step (1) is 0.0125 mol.

3. The method for preparing water-resistant, highly active modified manganese ore for remediation of antibiotic-contaminated soil according to claim 2, characterized in that, In step (2), 126.75 g of ferrous chloride was added to prepare modified manganese ore CFe(II)O3.

4. The method for preparing water-resistant, highly active modified manganese ore for remediation of antibiotic-contaminated soil according to claim 2, characterized in that, In step (2), the amount of ferrous chloride added is 26.33 g or 63.38 g, and modified manganese ore CFe(II)01 and CFe(II)02 are prepared respectively.

5. The application of a water-resistant, highly active modified manganese ore for antibiotic-contaminated soil remediation, characterized in that... The modified manganese ore is prepared by the manganese ore preparation method according to any one of claims 1 to 4.

6. The application of a water-resistant, highly active modified manganese ore for antibiotic-contaminated soil remediation according to claim 5, characterized in that, The antibiotic is any one or more of sulfamethoxazole, sulfadiazine, penicillin, cefotaxime, and thiamphenicol.

7. The application of a water-resistant, highly active modified manganese ore for antibiotic-contaminated soil remediation according to claim 6, characterized in that, Application methods include: 1) Air dry and grind the soil to be repaired, pass it through a 60-mesh sieve, and adjust the soil moisture content to 5%~200%; 2) Add the modified manganese ore at a ratio of 1.25% of the soil mass and mix thoroughly; 3) Soil remediation was completed after 7 days of constant temperature incubation in the dark.

8. The application of a water-resistant, highly active modified manganese ore for antibiotic-contaminated soil remediation according to claim 7, characterized in that, The modified manganese ore is the modified manganese ore CFe(II)O3 prepared according to claim 3.

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