Insecticidal double water agent and preparation method thereof

Abstract

The invention provides an insecticidal double-water agent and a preparation method thereof, and relates to the technical field of pesticides, the insecticidal double-water agent comprises the following raw materials by weight: 90-95 parts of a sulfonation liquid, 3-8 parts of 4-chlorobenzyl chloride and 4-9 parts of magnesium chips. The preparation method specifically comprises the following steps: S1, preparing a Grignard reagent; s2, preparing concentrated sulfonation liquid; s3, reacting dimehypo with chlorine to prepare chloride; s4, enabling the Grignard reagent to react with chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloro-1, 3-sodium dithiosulfonate propane; s5, enabling the 2-dimethylamino-2-p-chlorobenzyl chloro-1, 3-sodium dithiosulfonate propane to react with sodium thiosulfate, so as to prepare a sodium p-methanesulfonate insecticidal double-water agent; and S6, performing post-treatment on the sodium methanesulfonate insecticidal double water agent, and adding a synergist to obtain a final product. The dimehypo reagent prepared by the method disclosed by the invention is not crystallized at the high concentration of 36-43%, and the content of sodium hyposulfite is lower than 0.1%.

Description

Technical Field

[0001] The invention relates to the technical field of pesticides, and in particular to a dichlorvos aqueous solution and a preparation method thereof. Background Art

[0002] Dimehypo is a type of insecticide of the nereid poison class, a neurotoxin. After insects come into contact with and ingest the drug, they become sluggish, move slowly, lose the ability to attack crops, stop growing, soften, become paralyzed, and die. Since dimehypo has a good systemic conduction effect, it can be prepared into granules and spread on farmland, where it is absorbed and conducted by the roots of plants to kill pests.

[0003] The existing insecticide aqueous solution usually has a content of 32% and below (including 32%), but in the foreign trade market, compared with insecticide aqueous solutions with a content of 32% and below, high-content insecticide aqueous solutions (36% and above) are more likely to sell well, because with the same tonnage, high-content insecticide aqueous solutions can be used to prepare more low-content insecticide aqueous solutions.

[0004] At present, the main ingredients of insecticide aqueous solution include insecticide, sodium chloride and sodium thiosulfate. Usually, the sulfonated liquid (the mother liquor after the insecticide crystallizes) is concentrated and desalted (sodium chloride) to obtain a high-content insecticide aqueous solution. However, when the insecticide concentration is concentrated to 34% or above, crystals appear in the insecticide aqueous solution, affecting the use effect. At the same time, since the solubility of sodium thiosulfate increases with the increase of temperature, sodium thiosulfate cannot be removed by concentration, so that sodium thiosulfate remains in the aqueous solution, and the sodium thiosulfate content exceeds the standard, thereby affecting the normal production of crops. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides an insecticide-free aqueous solution and a preparation method thereof, which solves the technical problems that when the concentration of the existing insecticide-free aqueous solution is concentrated to more than 34%, crystallization easily occurs, affecting the use effect, and sodium thiosulfate residues in the aqueous solution exceed the standard, affecting the normal production of crops.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 90-95 parts of sulfonated liquid, 3-8 parts of 4-chlorobenzyl chloride and 4-9 parts of magnesium chips.

[0010] Preferably, the main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, wherein the concentration of dimethoate is 24-32%.

[0011] Preferably, 10 to 20 parts of synergist are also included.

[0012] Preferably, the synergist comprises 0.5 to 0.8 parts of a defoaming agent, 1 to 3 parts of ethylene glycol, 1 to 3 parts of a penetrant and 30 to 40 parts of a neonicotinoid synergist.

[0013] Preferably, the penetrant is any one of urea and ammonium nitrate.

[0014] Preferably, the neonicotinoid synergist is any one of thiacloprid, chlorthiazolin, dinotefuran, imidacloprid and acetamiprid.

[0015] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0016] S1. Slowly add 4-chlorobenzyl chloride to anhydrous ether and magnesium chips to react to obtain a Grignard reagent;

[0017] S2, the sulfonated liquid is concentrated to obtain a concentrated sulfonated liquid, wherein the sodium chloride in the concentrated sulfonated liquid is in a supersaturated state, and after cooling treatment, part of the sodium chloride crystals are precipitated and removed by filtration;

[0018] S3, chlorine gas is introduced into the concentrated sulfonated liquid, and the dimehypo in the liquid reacts with the chlorine gas to generate chloride;

[0019] S4, introducing the Grignard reagent into the solution after the reaction in step S3, and reacting the Grignard reagent with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphosulfonate propane;

[0020] S5, placing the solution obtained after the reaction in step S4 into a sulfonation kettle for heat preservation, and reacting the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disodium sulfopropane in the solution with sodium thiosulfate to obtain sodium p-methanesulfonate cyprodinil aqueous solution;

[0021] S6. Add sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0022] Preferably, the insulation time in S5 is 25 to 35 minutes.

[0023] Preferably, the insulation temperature in S5 is 73-83°C.

[0024] Preferably, the sodium hydroxide concentration in S6 is 30-40%.

[0025] (III) Beneficial effects

[0026] The present invention provides a sedative aqueous solution and a preparation method thereof. Compared with the prior art, the present invention has the following advantages:

[0027] Beneficial effects:

[0028] 1. The present invention introduces a 4-chlorobenzyl chloride group on the secondary carbon of dimehypo, so that when the dimehypo concentration is concentrated to 34% or more, specifically 36%-43%, no crystallization problem will occur, and the introduced 4-chlorobenzyl chloride group will not affect the specific chemical structure of dimehypo, and the insecticide effect of dimehypo aqueous solution can be improved.

[0029] 2. The technical solution of the present invention first uses 4-chlorobenzyl chloride to prepare a Grignard reagent, then reacts the Grignard reagent with the chlorination product of dimehypo to introduce a 4-chlorobenzyl chloride group on the secondary carbon of dimehypo to solve the problem that dimehypo is easy to crystallize when the concentration of dimehypo increases, and then reacts the reaction product of the 4-chlorobenzyl chloride group introduced on the secondary carbon with sodium thiosulfate in the sulfonated liquid to generate 2-dimethylamino-2-sodium p-toluenesulfonate-1,3-bis-sodium thiosulfonate propane (sodium p-toluenesulfonate dimehypo) to "eliminate" the sodium thiosulfate in the sulfonated liquid, thereby reducing the content of sodium thiosulfate in the final product dimehypo aqueous solution to avoid affecting the normal growth of crops.

[0030] 3. The technical solution of the present invention first concentrates the sulfonated liquid to make the sodium chloride in the sulfonated liquid reach a supersaturated state. After the concentrated sulfonated liquid is cooled to remove part of the crystallized sodium chloride, the remaining sodium chloride is still in a supersaturated state. When chlorine reacts with dimehypo in the concentrated sulfonated liquid, the saturated sodium chloride inhibits the reaction of chlorine with water in the concentrated sulfonated liquid to generate by-products such as sodium hypochlorite, and promotes the reaction of chlorine mainly with the secondary carbon of dimehypo, thereby improving the chloride yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 is the reaction formula of step S1 in the preparation method of Examples 1-3 of the present invention;

[0033] Figure 2 is the reaction formula of step S3 in the preparation method of Example 1-3 of the present invention;

[0034] Figure 3 is the reaction formula of step S4 in the preparation method of Example 1-3 of the present invention;

[0035] Figure 4 It is the reaction formula of step S5 in the preparation method of Example 1-3 of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. 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.

[0037] The embodiments of the present application provide a dimethoate aqueous solution and a preparation method thereof, thereby solving the technical problems that when the existing dimethoate aqueous solution is concentrated to a concentration of more than 34%, crystallization tends to occur, affecting the use effect, and sodium thiosulfate residues in the aqueous solution exceed the standard, affecting the normal production of crops.

[0038] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0039] Embodiment 1:

[0040] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 90 parts of sulfonated liquid, 8 parts of 4-chlorobenzyl chloride, 9 parts of magnesium chips, and 10 parts of synergist;

[0041] The synergist includes 0.5 parts of defoamer, 2 parts of ethylene glycol, 1 part of urea and 35 parts of thiacloprid;

[0042] The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, in which the concentration of dimethoate is 24%.

[0043] The active ingredient in the dimesulfuron aqueous solution is dimesulfuron sodium p-methylsulfonate, and its structural formula is as follows:

[0044]

[0045] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0046] S1. Anhydrous ether and magnesium chips are introduced into the reaction kettle. After nitrogen deoxygenation, 4-chlorobenzyl chloride is slowly added dropwise. After the reaction is completed, the reaction is filtered and then the ether is removed for purification to obtain the Grignard reagent. The reaction formula is as follows: Figure 1 As shown;

[0047] S2, concentrating the sulfonated liquid, filtering to remove sodium chloride, and obtaining a concentrated sulfonated liquid, wherein the main components of the concentrated sulfonated liquid are dimethoate and sodium thiosulfate;

[0048] S3, the concentrated sulfonated liquid is introduced into the reactor, and chlorine gas is introduced. The dimehypo in the concentrated sulfonated liquid reacts with the chlorine gas to generate chloride. The reaction formula is as follows: Figure 2 As shown;

[0049] S4, passing the Grignard reagent into the solution after the reaction in step S3, the Grignard reagent reacts with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane, the reaction formula is as follows: Figure 3 As shown;

[0050] S5, the solution after the reaction in step S4 is placed in a sulfonation kettle and kept warm for 30 minutes at a temperature of 75°C, and the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane in the solution reacts with sodium thiosulfate to obtain sodium p-toluene sulfonate chlorpyrifos aqueous solution, the reaction formula is as follows: Figure 4 As shown;

[0051] S6. Add 35% sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0052] Embodiment 2:

[0053] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 93 parts of sulfonated liquid, 3 parts of 4-chlorobenzyl chloride and 4 parts of magnesium chips, and 15 parts of synergist;

[0054] The synergist includes 0.8 parts of defoamer, 1 part of ethylene glycol, 2 parts of ammonium nitrate and 40 parts of chlorothioline;

[0055] The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, among which the concentration of dimethoate is 32%.

[0056] The active ingredient in the dimesulfuron aqueous solution is dimesulfuron sodium p-methylsulfonate, and its structural formula is as follows:

[0057]

[0058] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0059] S1. Anhydrous ether and magnesium chips are introduced into the reaction kettle. After nitrogen deoxygenation, 4-chlorobenzyl chloride is slowly added dropwise. After the reaction is completed, the reaction is filtered and then the ether is removed for purification to obtain the Grignard reagent. The reaction formula is as follows: Figure 1 As shown;

[0060] S2, concentrating the sulfonated liquid, filtering to remove sodium chloride, and obtaining a concentrated sulfonated liquid, wherein the main components of the concentrated sulfonated liquid are dimethoate and sodium thiosulfate;

[0061] S3, the concentrated sulfonated liquid is introduced into the reactor, and chlorine gas is introduced. The dimehypo in the concentrated sulfonated liquid reacts with the chlorine gas to generate chloride. The reaction formula is as follows: Figure 2 As shown;

[0062] S4, passing the Grignard reagent into the solution after the reaction in step S3, the Grignard reagent reacts with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane, the reaction formula is as follows: Figure 3 As shown;

[0063] S5, the solution after the reaction in step S4 is placed in a sulfonation kettle and kept warm for 30 minutes at a temperature of 75°C, and the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane in the solution reacts with sodium thiosulfate to obtain sodium p-toluene sulfonate chlorpyrifos aqueous solution, the reaction formula is as follows: Figure 4 As shown;

[0064] S6. Add 35% sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0065] Example 3

[0066] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 95 parts of sulfonated liquid, 6 parts of 4-chlorobenzyl chloride and 7 parts of magnesium chips, and 20 parts of synergist;

[0067] The synergist includes 0.6 parts of defoamer, 3 parts of ethylene glycol, 3 parts of urea and 30 parts of dinotefuran;

[0068] The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, among which the concentration of dimethoate is 29%.

[0069] The active ingredient in the dimesulfuron aqueous solution is dimesulfuron sodium p-methylsulfonate, and its structural formula is as follows:

[0070]

[0071] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0072] S1. Anhydrous ether and magnesium chips are introduced into the reaction kettle. After nitrogen deoxygenation, 4-chlorobenzyl chloride is slowly added dropwise. After the reaction is completed, the reaction is filtered and then the ether is removed for purification to obtain the Grignard reagent. The reaction formula is as follows: Figure 1 As shown;

[0073] S2, concentrating the sulfonated liquid, filtering to remove sodium chloride, and obtaining a concentrated sulfonated liquid, wherein the main components of the concentrated sulfonated liquid are dimethoate and sodium thiosulfate;

[0074] S3, the concentrated sulfonated liquid is introduced into the reactor, and chlorine gas is introduced. The dimehypo in the concentrated sulfonated liquid reacts with the chlorine gas to generate chloride. The reaction formula is as follows: Figure 2 As shown;

[0075] S4, passing the Grignard reagent into the solution after the reaction in step S3, the Grignard reagent reacts with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane, the reaction formula is as follows: Figure 3 As shown;

[0076] S5, the solution after the reaction in step S4 is placed in a sulfonation kettle and kept warm for 30 minutes at a temperature of 75°C, and the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane in the solution reacts with sodium thiosulfate to obtain sodium p-toluene sulfonate chlorpyrifos aqueous solution, the reaction formula is as follows: Figure 4 As shown;

[0077] S6. Add 35% sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0078] Example 4

[0079] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 95 parts of sulfonated liquid, 8 parts of 4-chlorobenzyl chloride and 9 parts of magnesium chips, and 20 parts of synergist;

[0080] The synergist includes 0.8 parts of defoamer, 1 part of ethylene glycol, 2 parts of ammonium nitrate and 40 parts of imidacloprid;

[0081] The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, among which the concentration of dimethoate is 29%.

[0082] The active ingredient in the dimesulfuron aqueous solution is dimesulfuron sodium p-methylsulfonate, and its structural formula is as follows:

[0083]

[0084] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0085] S1. Anhydrous ether and magnesium chips are introduced into the reaction kettle. After nitrogen deoxygenation, 4-chlorobenzyl chloride is slowly added dropwise. After the reaction is completed, the reaction is filtered and then the ether is removed for purification to obtain the Grignard reagent. The reaction formula is as follows: Figure 1 As shown;

[0086] S2, concentrating the sulfonated liquid, filtering to remove sodium chloride, and obtaining a concentrated sulfonated liquid, wherein the main components of the concentrated sulfonated liquid are dimethoate and sodium thiosulfate;

[0087] S3, the concentrated sulfonated liquid is introduced into the reactor, and chlorine gas is introduced. The dimehypo in the concentrated sulfonated liquid reacts with the chlorine gas to generate chloride. The reaction formula is as follows: Figure 2 As shown;

[0088] S4, passing the Grignard reagent into the solution after the reaction in step S3, the Grignard reagent reacts with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane, the reaction formula is as follows: Figure 3 As shown;

[0089] S5, the solution after the reaction in step S4 is placed in a sulfonation kettle and kept warm for 30 minutes at a temperature of 75°C, and the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane in the solution reacts with sodium thiosulfate to obtain sodium p-toluene sulfonate chlorpyrifos aqueous solution, the reaction formula is as follows: Figure 4 As shown;

[0090] S6. Add 35% sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0091] Example 5

[0092] The insecticide double aqueous solution comprises the following raw materials in parts by weight: 90 parts of sulfonated liquid, 3 parts of 4-chlorobenzyl chloride and 4 parts of magnesium chips, and 15 parts of synergist;

[0093] The synergist includes 0.6 parts of defoamer, 3 parts of ethylene glycol, 3 parts of urea and 30 parts of acetamiprid;

[0094] The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, among which the concentration of dimethoate is 29%.

[0095] The active ingredient in the dimesulfuron aqueous solution is dimesulfuron sodium p-methylsulfonate, and its structural formula is as follows:

[0096]

[0097] The preparation method of the dichlorvos aqueous solution specifically comprises the following steps:

[0098] S1. Anhydrous ether and magnesium chips are introduced into the reaction kettle. After nitrogen deoxygenation, 4-chlorobenzyl chloride is slowly added dropwise. After the reaction is completed, the reaction is filtered and then the ether is removed for purification to obtain the Grignard reagent. The reaction formula is as follows: Figure 1 As shown;

[0099] S2, concentrating the sulfonated liquid, filtering to remove sodium chloride, and obtaining a concentrated sulfonated liquid, wherein the main components of the concentrated sulfonated liquid are dimethoate and sodium thiosulfate;

[0100] S3, the concentrated sulfonated liquid is introduced into the reactor, and chlorine gas is introduced. The dimehypo in the concentrated sulfonated liquid reacts with the chlorine gas to generate chloride. The reaction formula is as follows: Figure 2 As shown;

[0101] S4, passing the Grignard reagent into the solution after the reaction in step S3, the Grignard reagent reacts with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane, the reaction formula is as follows: Figure 3 As shown;

[0102] S5, the solution after the reaction in step S4 is placed in a sulfonation kettle and kept warm for 30 minutes at a temperature of 75°C, and the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphide sulfonate propane in the solution reacts with sodium thiosulfate to obtain sodium p-toluene sulfonate chlorpyrifos aqueous solution, the reaction formula is as follows: Figure 4 As shown;

[0103] S6. Add 35% sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

[0104] Comparative Example 1

[0105] The sulfonated liquid in Example 1 was directly concentrated, and the synergist described in Example 1 was added to the concentrated liquid so that the concentration of the dimethoate was the same as that of the final product dimethoate aqueous solution in Example 1.

[0106] Comparative Example 2

[0107] The sulfonated liquid in Example 2 was directly concentrated, and the synergist described in Example 2 was added to the concentrated liquid so that the concentration of the dimethoate was the same as that of the final product dimethoate aqueous solution in Example 1.

[0108] Comparative Example 3

[0109] The sulfonated liquid in Example 3 was directly concentrated, and the synergist described in Example 3 was added to the concentrated liquid so that the concentration of the dimethoate was the same as that of the final product dimethoate aqueous solution in Example 1.

[0110] Performance Testing

[0111] The dimethoate aqueous solution prepared in Examples 1-3 and Comparative Examples 1-3 were placed in a refrigerator respectively, and observed for crystallization according to the method for determining the low temperature stability of pesticides in GB / T19137-2003, and the content of sodium thiosulfate in the dimethoate aqueous solution was detected. The results are shown in Tables 1 and 2 below:

[0112] Table 1-6 Sodium thiosulfate content in samples

[0113] sample Content of dimethoate Sodium thiosulfate content Comparative Example 1 40％ 6.2％ Comparative Example 2 45％ 8.3 Comparative Example 3 42.5％ 7.4％ Example 1 40％ 0.06％ Example 2 45％ 0.08％ Example 3 42.5％ 0.07％

[0114] Table 2-6 Low temperature stability test results of dichlorvos aqueous solution in samples

[0115]

[0116] Note: “√” indicates crystallization, and “×” indicates non-crystallization.

[0117] From the data in Table 1 and Table 2, we can see that:

[0118] 1. The sodium thiosulfate content of the insecticide aqueous solution prepared by the technical solution of the present invention is less than 0.1%, and the impact on the normal growth of crops is almost negligible;

[0119] 2. When the concentration of the insecticide double aqueous solution is above 40%, it will not produce crystallization problem even after being placed for 3 months or even half a year. Compared with the prior art insecticide double aqueous solution which will start to crystallize at a concentration of 34%, the present invention greatly improves the stability and application range of the insecticide double aqueous solution.

[0120] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0121] 1. The present invention introduces a 4-chlorobenzyl chloride group on the secondary carbon of dimehypo, so that when the dimehypo concentration is concentrated to 34% or more, there will be no crystallization problem, and the introduced 4-chlorobenzyl chloride group will not affect the specific chemical structure of dimehypo, and the insecticide effect of dimehypo aqueous solution can be improved.

[0122] 2. The technical solution of the present invention first uses 4-chlorobenzyl chloride to prepare a Grignard reagent, then reacts the Grignard reagent with the chlorination product of dimehypo to introduce a 4-chlorobenzyl chloride group on the secondary carbon of dimehypo to solve the problem that dimehypo is easy to crystallize when the concentration of dimehypo increases, and then reacts the reaction product of the 4-chlorobenzyl chloride group introduced on the secondary carbon with sodium thiosulfate in the sulfonated liquid to generate 2-dimethylamino-2-sodium p-toluenesulfonate-1,3-bis-sodium thiosulfonate propane (sodium p-toluenesulfonate dimehypo) to "eliminate" the sodium thiosulfate in the sulfonated liquid, thereby reducing the content of sodium thiosulfate in the final product dimehypo aqueous solution to avoid affecting the normal growth of crops.

[0123] 3. The technical solution of the present invention first concentrates the sulfonated liquid to make the sodium chloride in the sulfonated liquid reach a supersaturated state. After the concentrated sulfonated liquid is cooled to remove part of the crystallized sodium chloride, the remaining sodium chloride is still in a supersaturated state. When chlorine reacts with dimehypo in the concentrated sulfonated liquid, the saturated sodium chloride inhibits the reaction of chlorine with water in the concentrated sulfonated liquid to generate by-products such as sodium hypochlorite, and promotes the reaction of chlorine mainly with the secondary carbon of dimehypo, thereby improving the chloride yield.

[0124] 4. The present invention further improves the toxicity range of high-content dimethoate by adding a synergist.

[0125] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0126] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cypermethrin aqueous solution, characterized in that: The method comprises the following raw materials in parts by weight: 90-95 parts of sulfonation liquid, 3-8 parts of 4-chlorobenzyl chloride and 4-9 parts of magnesium chips.

2. The insecticide-free water preparation as claimed in claim 1, characterized in that The main components of the sulfonated liquid include dimethoate, sodium chloride and sodium thiosulfate, wherein the concentration of the dimethoate is 24-32%.

3. The insecticide-free water preparation as claimed in claim 1, characterized in that Also includes 10 to 20 parts of synergist.

4. The insecticide-free water preparation as claimed in claim 3, characterized in that The synergist comprises 0.5 to 0.8 parts of a defoaming agent, 1 to 3 parts of ethylene glycol, 1 to 3 parts of a penetrant and 30 to 40 parts of a neonicotinoid synergist.

5. The insecticide-free water preparation as claimed in claim 4, characterized in that The penetrant is any one of urea and ammonium nitrate.

6. The insecticide-free water preparation as claimed in claim 4, characterized in that The neonicotinoid synergist is any one of thiacloprid, chlorthiazolin, dinotefuran, imidacloprid and acetamiprid.

7. The method for preparing the dichlorvos aqueous solution according to any one of claims 1 to 6, characterized in that: The specific steps include: S1. Slowly add 4-chlorobenzyl chloride to anhydrous ether and magnesium chips to react to obtain a Grignard reagent; S2, the sulfonated liquid is concentrated to obtain a concentrated sulfonated liquid, wherein the sodium chloride in the concentrated sulfonated liquid is in a supersaturated state, and after cooling treatment, part of the sodium chloride crystals are precipitated and removed by filtration; S3, chlorine gas is introduced into the concentrated sulfonated liquid, and the dimehypo in the liquid reacts with the chlorine gas to generate chloride; S4, introducing the Grignard reagent into the solution after the reaction in step S3, and reacting the Grignard reagent with the chloride to generate 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disulphosulfonate propane; S5, placing the solution obtained after the reaction in step S4 into a sulfonation kettle for heat preservation, and reacting the 2-dimethylamino-2-p-chlorobenzyl chloride-1,3-sodium disodium sulfopropane in the solution with sodium thiosulfate to obtain sodium p-methanesulfonate cyprodinil aqueous solution; S6. Add sodium hydroxide solution to the sodium p-methylsulfonate insecticide aqueous solution, filter out magnesium salt, concentrate, filter out sodium chloride, add the synergist and mix well to obtain the final product insecticide aqueous solution.

8. The method for preparing the dichlorvos aqueous solution as claimed in claim 7, characterized in that: The insulation time in S5 is 25 to 35 minutes.

9. The method for preparing the dichlorvos aqueous solution as claimed in claim 7, characterized in that: The insulation temperature in S5 is 73-83°C.

10. The method for preparing the dichlorvos aqueous solution as claimed in claim 7, characterized in that: The sodium hydroxide concentration in S6 is 30-40%.

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