Preparation method of dispersible oil suspending agent containing mesosulfuron-methyl herbicide
By using methyl oleate as a solvent in the dispersible oil suspension agent of methyl disulfuron herbicide, and adding additives such as pyrazole detoxification and emulsifier, combined with specific stabilizer formulas and process treatment, the problem of methyl disulfuron being easy to settle and decompose during the shelf life of the product is solved, and the stability and storage of the product are improved.
Patent Information
- Application Number
- CN202411824473.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-03-07
AI Technical Summary
The active component methyl disulfuron in dispersible oil suspension agent is prone to sedimentation, decomposition and unstable during the shelf life of the product.
Methyl oleate is used as solvent, additives such as pyrazole oleate and emulsifier are added, and the methyldisulfuron-containing herbicide dispersible oil suspension agent is prepared through specific stabilizer formulas and processes.
It significantly improves the stability, heat storage and long-term storage of methyldisulfuron herbicides at room temperature, and reduces the decomposition rate of active ingredients.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of herbicides, in particular to a method for preparing a dispersible oil suspension containing a mesosulfuron herbicide. Background Art
[0002] Mesosulfuron-methyl is a highly effective sulfonylurea herbicide, mainly suitable for soft or semi-hard wheat varieties. It can be absorbed by the stems and leaves of weeds, inhibit the activity of acetolactate synthase in the weeds, hinder cell division, and cause the weeds to die. Mesosulfuron-methyl herbicide can effectively control a variety of annual grass weeds, such as wild oats, brome, and aesculus, and also control some broad-leaved weeds, such as chickweed and shepherd's purse. Generally, weeds will stop growing 2 days after using mesosulfuron-methyl, and die within 2 to 4 weeks. Therefore, it needs to be used with safeners such as pyraclostrobin to promote its rapid decomposition in crops without affecting its control of sensitive weeds. In addition, mesosulfuron-methyl also has the advantages of low acute / chronic toxicity, low residue in crops, and little impact on animals such as birds, fish, and soil microorganisms. It can be seen that mesosulfuron-methyl herbicide has a wide range of application prospects. However, the active ingredient methyl disulfone in the current methyl disulfone dispersible oil suspension concentrate is prone to sedimentation, decomposition and instability during the shelf life of the product. Therefore, through the research on methyl disulfone dispersible oil suspension concentrate, the physical and chemical properties of methyl disulfone are ensured to be stable during the shelf life of the product, providing reliable technical support for the further promotion of this product. Summary of the invention
[0003] The purpose of the present invention is to provide a method for preparing a dispersible oil suspension containing a mesosulfuron herbicide, so as to solve the problem that the active component mesosulfuron in the mesosulfuron dispersible oil suspension is easy to settle, decompose and be unstable during the shelf life of the product.
[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: A dispersible oil suspension containing a methyl disulfuron-methyl herbicide. The dosage of each component in the dispersible oil suspension containing the methyl disulfuron-methyl herbicide is, by mass fraction, 1% to 10% of methyl disulfuron-methyl, 3% to 30% of mefenpyr-butyl, 8% to 20% of soybean oil, 5% to 15% of an emulsifier, 1% to 5% of a stabilizer, and the rest is methyl oleate.
[0005] As a limitation of the present invention, the amounts of the components in the dispersible oil suspension concentrate containing the methyl disulfuron-methyl herbicide are, by mass fraction, 3% of methyl disulfuron-methyl, 9% of mefenacet-butyl, 10% of soybean oil, 15% of emulsifier, 2.5% of stabilizer, and the rest is methyl oleate.
[0006] As a limitation of the present invention, the emulsifier is a combination of one or more of calcium dodecylbenzene sulfonate, castor oil polyoxyethylene ether phosphate, fatty alcohol polyoxyethyl ether, and tristyrylphenol polyoxyethylene ether sulfonate.
[0007] As a limitation of the present invention, in the emulsifier, the mass ratio of calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate is 7:5:3.
[0008] As a limitation of the present invention, the amounts of the components in the stabilizer are, by weight, 10 to 12 parts of white carbon black, 22 to 65 parts of kaolin, 28 to 32 parts of urea, and 28 to 34 parts of 1,4-butanesultone.
[0009] A method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, specifically comprising: Step 1: Add urea and 1,4-butanesulfonate to deionized water in sequence, mix well, heat to 70-90°C, stir for 0.5-1.5h, add white carbon black and kaolin, stir well, cool to room temperature, spray dry, and obtain a stabilizer; Step 2: Mix methyl disulfone, mefenpyr, emulsifier, stabilizer, methyl oleate and soybean oil, stir evenly, wet sand grind for 2 to 3 hours, filter after sand grinding, and obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0010] As a limitation of the present invention, in step 1, the kaolin used may be modified with hexadecyltrimethylammonium chloride, specifically: The kaolin and the cetyltrimethylammonium chloride solution were mixed evenly, stirred for 10 to 20 minutes at room temperature to allow them to react fully, centrifuged after the reaction was completed, washed with water, dried and activated at 95 to 105°C for 9 to 11 hours, ground after drying, and sieved to obtain the cetyltrimethylammonium chloride modified kaolin.
[0011] As a limitation of the present invention, in step 2, oligomeric ricinoleic acid pentaerythritol ester may also be added, and the preparation method of oligomeric ricinoleic acid pentaerythritol ester is as follows: The ricinoleic acid, xylene and stannous chloride dihydrate were mixed and stirred evenly, and reacted for 12 to 16 hours at 170 to 190° C. and 100 to 300 rpm under nitrogen as protective gas. After the reaction was completed, the mixture was cooled, and pentaerythritol was added. The mixture was heated to 160 to 180° C. and the reaction was continued for 6 to 10 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled to obtain oligomeric ricinoleic acid pentaerythritol ester.
[0012] Compared with the prior art, the present invention has the following beneficial effects: The invention uses methyl oleate as a solvent and adds additives such as mefenpyr and an emulsifier to prepare a dispersible oil suspension containing a methyl disulfone herbicide. The suspension has good stability, heat storage properties and long-term storage properties at room temperature, and the decomposition rate of the active ingredient methyl disulfone is low after heat storage or long-term storage at room temperature.
[0013] The use of hexadecyltrimethylammonium chloride to modify kaolin not only increases the viscosity of the suspension system, but also increases the surface charge number and specific surface area of kaolin, expands the structural channels in kaolin, loads organic groups with good hydrophobicity to improve the hydrophobicity of kaolin, and improves the adsorption capacity of methyl disulfone particles to prevent them from settling to the bottom.
[0014] Oligomeric castor oil pentaerythritol ester is added as a dispersant for the suspending agent, wherein the hydroxyl anchoring group on the dispersant can be well combined with the surface of the active ingredient methyl disulfone particles to prevent desorption, and the solvated chain is a polyricinoleic acid chain, which contains unsaturated double bonds and has good oil solubility, and can make the active ingredient methyl disulfone particles evenly dispersed in methyl oleate, and is not easy to agglomerate and precipitate. DETAILED DESCRIPTION
[0015] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0016] Methyl disulfone (purity: 98%) and pyraclostrobin (purity: 99%) were provided by Shandong Binnong, calcium dodecylbenzenesulfonate (2023021701), tristyrylphenol polyoxyethylene ether sulfonate (2022120702), castor oil polyoxyethylene ether phosphate (2023011901), and fatty alcohol polyoxyethyl ether (2023011702) were provided by Nanjing Taihua Chemical Industry, and the remaining materials are industrial products and can be purchased on the market.
[0017] Example 1: A method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, specifically: Step 1: Prepare the stabilizer By mass, 30 parts of urea and 30 parts of 1,4-butanesulfonate were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 10 parts of white carbon black and 30 parts of kaolin were added, stirred evenly, cooled to room temperature, spray-dried, and a stabilizer was obtained.
[0018] Step 2: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 3 parts of methyl disulfone, 9 parts of pyraclostrobin, 15 parts of emulsifier, 2.5 parts of stabilizer, 60.5 parts of methyl oleate and 10 parts of soybean oil were mixed, stirred evenly, wet sand milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0019] In this embodiment, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0020] Example 2: A method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, specifically: Step 1: Prepare the stabilizer By mass, 30 parts of urea and 30 parts of 1,4-butanesulfonate were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 10 parts of white carbon black and 30 parts of kaolin were added, stirred evenly, cooled to room temperature, spray-dried, and a stabilizer was obtained.
[0021] Step 2: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 2 parts of methyl disulfone, 8 parts of pyraclostrobin, 14 parts of emulsifier, 2 parts of stabilizer, 65 parts of methyl oleate and 9 parts of soybean oil were mixed, stirred evenly, wet sand milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0022] In this embodiment, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0023] Example 3: A method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, specifically: Step 1: Prepare the stabilizer By mass, 30 parts of urea and 30 parts of 1,4-butanesulfonate were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 10 parts of white carbon black and 30 parts of kaolin were added, stirred evenly, cooled to room temperature, spray-dried, and a stabilizer was obtained.
[0024] Step 2: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 4 parts of methyl disulfone, 10 parts of pyraclostrobin, 16 parts of emulsifier, 3 parts of stabilizer, 56 parts of methyl oleate and 11 parts of soybean oil were mixed, stirred evenly, wet sand milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0025] In this embodiment, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0026] Example 4: A method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, specifically: Step 1: Preparation of hexadecyltrimethylammonium chloride modified kaolin By mass, 5 parts of kaolin and 15 parts of 0.01 mol / L hexadecyltrimethylammonium chloride solution were mixed evenly, stirred at room temperature for 15 minutes to allow them to react fully, and after the reaction was completed, centrifuged, washed, dried and activated at 100°C for 10 hours, dried, ground, and sieved to obtain hexadecyltrimethylammonium chloride modified kaolin.
[0027] Step 2: Prepare the stabilizer By mass, 30 parts of urea and 30 parts of 1,4-butanesulfonate were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 10 parts of white carbon black and 30 parts of hexadecyltrimethylammonium chloride-modified kaolin were added, stirred evenly, cooled to room temperature, spray-dried, and a stabilizer was obtained.
[0028] Step 3: Preparation of pentaerythritol oligomeric ricinoleate By mass, 94 parts of ricinoleic acid, 13 parts of xylene and 0.5 parts of stannous chloride dihydrate were mixed and stirred evenly, and reacted for 14 hours at 180°C and 200rpm under nitrogen as protective gas. After the reaction was completed, the mixture was cooled, 27.45 parts of pentaerythritol were added, the temperature was raised to 170°C and the reaction was continued for 8 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled to obtain oligomeric ricinoleic acid pentaerythritol ester.
[0029] Step 4: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 3 parts of methyl disulfone, 9 parts of pyraclostrobin, 15 parts of emulsifier, 2.5 parts of stabilizer, 56 parts of methyl oleate, 10 parts of soybean oil, and 4.5 parts of pentaerythritol oligomeric ricinoleate were mixed, stirred evenly, wet-milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0030] In this embodiment, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0031] The following are comparative experiments based on Example 1, specifically Comparative Example 1, Comparative Example 2, and Comparative Example 3, as described below: Comparative Example 1: This comparative example relates to a method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, and the difference from Example 1 is only that the content of each component in the stabilizer is changed. Specifically: Step 1: Prepare the stabilizer By mass, 10 parts of urea and 10 parts of 1,4-butanesulfonic acid lactone were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 20 parts of white carbon black and 60 parts of kaolin were added, stirred evenly, cooled to room temperature, spray dried, and a stabilizer was obtained.
[0032] Step 2: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 3 parts of methyl disulfone, 9 parts of pyraclostrobin, 15 parts of emulsifier, 2.5 parts of stabilizer, 60.5 parts of methyl oleate and 10 parts of soybean oil were mixed, stirred evenly, wet sand milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0033] In this comparative example, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0034] Comparative Example 2: This comparative example relates to a method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, which differs from Example 1 only in that no stabilizer is used. Specifically: Step 1: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 3 parts of methyl disulfone, 9 parts of pyraclostrobin, 15 parts of emulsifier, 63 parts of methyl oleate and 10 parts of soybean oil were mixed, stirred evenly, wet sand milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0035] In this comparative example, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0036] Comparative Example 3: This comparative example relates to a method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide, which differs from Example 1 only in that oligomeric ricinoleic acid pentaerythritol ester is added. Specifically: Step 1: Prepare the stabilizer By mass, 30 parts of urea and 30 parts of 1,4-butanesulfonate were added to 100 parts of deionized water in sequence, mixed evenly, heated to 80°C, stirred for 1 hour, 10 parts of white carbon black and 30 parts of kaolin were added, stirred evenly, cooled to room temperature, spray-dried, and a stabilizer was obtained.
[0037] Step 2: Preparation of pentaerythritol oligomeric ricinoleate By mass, 94 parts of ricinoleic acid, 13 parts of xylene and 0.5 parts of stannous chloride dihydrate were mixed and stirred evenly, and reacted for 14 hours at 180°C and 200rpm under nitrogen as protective gas. After the reaction was completed, the mixture was cooled, 27.45 parts of pentaerythritol were added, the temperature was raised to 170°C and the reaction was continued for 8 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled to obtain oligomeric ricinoleic acid pentaerythritol ester.
[0038] Step 3: Preparation of a dispersible oil suspension containing mesosulfuron-methyl herbicide By mass, 3 parts of methyl disulfone, 9 parts of pyraclostrobin, 15 parts of emulsifier, 2.5 parts of stabilizer, 56 parts of methyl oleate, 10 parts of soybean oil, and 4.5 parts of pentaerythritol oligomeric ricinoleate were mixed, stirred evenly, wet-milled for 2.5 hours, and filtered after sand milling to obtain a dispersible oil suspension containing methyl disulfone herbicide.
[0039] In this comparative example, the emulsifier is prepared by compounding calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate in a mass ratio of 7:5:3.
[0040] Detection experiment: According to the processes in Example 1, Example 2, Example 3, Example 4, Comparative Example 1, Comparative Example 2, and Comparative Example 3, the dispersible oil suspension sample containing methyl disulfone herbicide required for the detection experiment was prepared.
[0041] Suspension rate determination: Test according to the "Determination of Suspension Rate of Pesticides" (GB / T 14825-2006). Take 5mL of the sample to be tested and weigh it, then add it to a 250mL beaker containing 50mL of 30℃ standard hard water (pH=6.8, calcium carbonate content: 342mg / L). Shake the beaker by hand for 2min, 120 times per minute, to mix it evenly. After shaking, place the mixed solution and the beaker in a 30℃ water bath for 4min. After the insulation is completed, transfer the mixed solution in the beaker to the 250mL volume. The beaker is rinsed with the above-mentioned standard hard water, and the rinse liquid is also added to the measuring cylinder, and the measuring cylinder is titrated to the 250mL scale line with the above-mentioned standard hard water. After the measuring cylinder is sealed, the measuring cylinder is repeatedly turned upside down 30 times within 1 minute, and the seal is removed to avoid direct sunlight. The measuring cylinder is placed in a 30℃ constant temperature water bath and allowed to stand for 30 minutes. The upper 225mL mixed liquid in the measuring cylinder is sucked out with a pipette, and the bottom 25mL mixed liquid is dried to constant weight, the amount of residual substance is weighed, and the suspension rate of the sample is calculated.
[0042] Thermal storage stability test: The test is carried out in accordance with the "Method for Determination of Thermal Storage Stability of Pesticides" (GB / T 19136-2021). The sample to be tested is taken to determine the content of mesosulfuron in the sample, and the sample is placed in a sealed glass bottle and stored in a 54°C constant temperature box for 14 days. After 14 days, the glass bottle is taken out and placed in a dryer to cool to room temperature. The suspension rate of the sample and the content of mesosulfuron are measured, and the suspension rate of the sample after thermal storage and the decomposition rate of the active ingredient are calculated.
[0043] Room temperature storage stability test: Refer to the "Stability Test Method for Pesticide Emulsion" (GB / T 1603-2001) for testing, take the sample to be tested to determine the content of methyl disulfone in the sample, place the sample in a sealed glass bottle, store it indoors at room temperature for 12 months under natural conditions, take it out after 12 months, observe the appearance of the sample and measure the content of methyl disulfone in the sample, and calculate the decomposition rate of the active ingredient after the sample is stored at room temperature. Appearance judgment standard: Precipitation may occur after long-term storage, but after shaking, it should resume swimming and should not clump.
[0044]
[0045] Conclusion: According to the test data, it can be seen that the dispersible oil suspension concentrate containing the mesosulfuron herbicide of the present invention has excellent dispersibility, heat storage stability and long-term storage at room temperature.
[0046] From the comparison of the data of Comparative Examples 1 and 2 with Example 1, it can be seen that the stabilizer of methyl disulfone requires a specific amount of raw materials to be added and a ratio of the stabilizer. After the content of each component of the stabilizer in Comparative Example 1 is changed, the thermal storage decomposition rate of methyl disulfone and the decomposition rate of storage at room temperature are significantly higher than those in Example 1. No stabilizer is added in Comparative Example 2, resulting in a higher thermal storage decomposition rate of methyl disulfone and a higher decomposition rate of long-term storage at room temperature than in Example 1 and Comparative Example 1.
[0047] From the data of Comparative Example 3 compared with Example 1, it can be seen that the addition of pentaerythritol oligomeric ricinoleate has a positive effect on improving the suspension rate of the dispersible oil suspension concentrate containing the mesosulfuron herbicide, the decomposition rate of mesosulfuron during hot storage, and the decomposition rate of long-term storage at room temperature.
[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.
Claims
1. A dispersible oil suspension containing mesosulfuron-methyl herbicide, characterized in that: Calculated by mass fraction, the dosage of each component in the dispersible oil suspension containing methyl disulfuron-methyl herbicide is: 1% to 10% of methyl disulfuron-methyl, 3% to 30% of pyraclostrobin, 8% to 20% of soybean oil, 5% to 15% of emulsifier, 1% to 5% of stabilizer, and the rest is methyl oleate.
2. The dispersible oil suspension concentrate containing mesosulfuron-methyl herbicide according to claim 1, characterized in that: Calculated by mass fraction, the dosage of each component in the dispersible oil suspension containing the methyl disulfuron-methyl herbicide is: 3% of methyl disulfuron-methyl, 9% of mefenacet-butyl, 10% of soybean oil, 15% of emulsifier, 2.5% of stabilizer, and the rest is methyl oleate.
3. The dispersible oil suspension concentrate containing mesosulfuron-methyl herbicide according to claim 1, characterized in that: The emulsifier is a combination of one or more of calcium dodecylbenzene sulfonate, castor oil polyoxyethylene ether phosphate, fatty alcohol polyoxyethyl ether, and tristyrylphenol polyoxyethylene ether sulfonate.
4. The dispersible oil suspension concentrate containing mesosulfuron-methyl herbicide according to claim 3, characterized in that: In the emulsifier, the mass ratio of calcium dodecylbenzene sulfonate, tristyrylphenol polyoxyethylene ether sulfonate and castor oil polyoxyethylene ether phosphate is 7:5:
3.
5. The dispersible oil suspension concentrate containing mesosulfuron-methyl herbicide according to claim 1, characterized in that: Calculated by mass, the dosage of each component in the stabilizer is: 10 to 12 parts of white carbon black, 22 to 65 parts of kaolin, 28 to 32 parts of urea, and 28 to 34 parts of 1,4-butanesulfonate.
6. A method for preparing a dispersible oil suspension containing a mesosulfuron herbicide, characterized in that: Specifically: Step 1: Add urea and 1,4-butanesulfonate to deionized water in sequence, mix well, heat to 70-90°C, stir for 0.5-1.5h, add white carbon black and kaolin, stir well, cool to room temperature, spray dry, and obtain a stabilizer; Step 2: Mix methyl disulfone, mefenpyr, emulsifier, stabilizer, methyl oleate and soybean oil, stir evenly, wet sand grind for 2 to 3 hours, filter after sand grinding, and obtain a dispersible oil suspension containing methyl disulfone herbicide.
7. The method for preparing a dispersible oil suspension containing mesosulfuron-methyl herbicide according to claim 6, characterized in that: In step 1, the kaolin used can be modified with hexadecyltrimethylammonium chloride, specifically: The kaolin and the cetyltrimethylammonium chloride solution were mixed evenly, stirred for 10 to 20 minutes at room temperature to allow them to react fully, centrifuged after the reaction was completed, washed with water, dried and activated at 95 to 105°C for 9 to 11 hours, ground after drying, and sieved to obtain the cetyltrimethylammonium chloride modified kaolin.
8. The method for preparing a dispersible oil suspension concentrate containing mesosulfuron-methyl herbicide according to claim 6, characterized in that: In step 2, oligomeric ricinoleic acid pentaerythritol ester may also be added, and the preparation method of oligomeric ricinoleic acid pentaerythritol ester is as follows: The ricinoleic acid, xylene and stannous chloride dihydrate were mixed and stirred evenly, and reacted for 12 to 16 hours at 170 to 190° C. and 100 to 300 rpm under nitrogen as protective gas. After the reaction was completed, the mixture was cooled, and pentaerythritol was added. The mixture was heated to 160 to 180° C. and the reaction was continued for 6 to 10 hours. After the reaction was completed, the mixture was cooled, filtered, and the filtrate was distilled to obtain oligomeric ricinoleic acid pentaerythritol ester.