1. A preparation method of glyphosate technical is characterized by comprising the following preparation steps:

carrying out addition reaction on methanol, triethylamine, paraformaldehyde and glycine, then adding dimethyl phosphite for condensation reaction to obtain an intermediate product, dropwise adding a hydrochloric acid solution into the intermediate product, adding a phosphate ester amphoteric surfactant, and reacting to obtain a glyphosate technical product;

wherein the phosphate ester amphoteric surfactant is prepared by the following steps:

step S11, reacting sodium dihydrogen phosphate water solution with epichlorohydrin at the temperature of 105-110 ℃ for 4h, removing solvent water by rotary evaporation, dissolving the product with ethanol, and then recrystallizing and drying to obtain an intermediate 1;

step S12, adding fatty acid into a three-neck flask, introducing nitrogen, heating to 120-130 ℃, adding N, N-dimethyl-1, 3-propanediamine, reacting for 8h at 150 ℃, performing reduced pressure distillation, recrystallizing for 3-4 times by using petroleum ether, and drying to obtain an intermediate 2;

and step S13, adding the intermediate 1, the intermediate 2 and an ethanol solution into a three-neck flask, and reacting for 8 hours at 85 ℃ to obtain the phosphate ester amphoteric surfactant.

2. The method for preparing glyphosate technical material according to claim 1, which is characterized in that: the mass ratio of methanol, triethylamine, paraformaldehyde, glycine and dimethyl phosphite is 1: 4.3: 4.1: 4.9: 2.2.

3. the method for preparing glyphosate technical material according to claim 1, which is characterized in that: the mass ratio of the intermediate product to the hydrochloric acid solution to the phosphate ester amphoteric surfactant is 1.2-1.5: 100: 9-11.

4. The method for preparing glyphosate technical material according to claim 1, which is characterized in that: in the step S11, the mass fraction of the sodium dihydrogen phosphate aqueous solution is 40 to 50%, and the molar ratio of the sodium dihydrogen phosphate to the epichlorohydrin is 1: 1.2.

5. the method for preparing glyphosate technical material according to claim 1, which is characterized in that: in step S12, the molar ratio of N, N-dimethyl-1, 3-propanediamine to fatty acid is 1: 1.15.

6. the method for preparing glyphosate technical material according to claim 1, which is characterized in that: in the step S13, the mass ratio of the intermediate 2 to the intermediate 1 to the ethanol solution is 1: 1: 15.4-20.2.

Background

Glyphosate is a non-selective and residue-free biocidal herbicide, is very effective on perennial rooting weeds, and is widely used in rubber, mulberry, tea, orchards and sugarcane fields. Mainly inhibits enol pyruvyl shikimic acid phosphate synthetase in plants, thereby inhibiting the conversion of shikimic acid to phenylalanine, tyrosine and tryptophan, interfering protein synthesis and leading to plant death. Glyphosate is absorbed by stems and leaves and then transferred to various parts of plants, and can prevent and kill monocotyledons, dicotyledons, annual and perennial plants, herbaceous plants, shrubs and other plants of more than 40 families. After entering the soil, the glyphosate is combined with metal ions such as iron, aluminum and the like quickly to lose activity. The hydrolysis process of the glyphosate comprises the following steps: adding measured methanol, triethylamine and paraformaldehyde into a synthesis kettle, and adding into aminoacetic acid to perform addition reaction; then slowly adding dimethyl phosphite, carrying out condensation reaction at 50 ℃, and keeping for 1-1.5 h; after the reaction is finished, transferring the mixture into a hydrolysis kettle, introducing cooling water into a jacket, dropwise adding hydrochloric acid, keeping the temperature at 50 ℃ for 1h, condensing chloromethane generated in the hydrolysis process, removing a chloromethane production device, and recovering condensed liquid methylal; the process has low production efficiency and low product yield, and generates a large amount of wastewater in the production process, thereby having high labor intensity.

According to the thermochemical theory, the hydrolysis reaction of the glyphosate is an endothermic reaction, the concentration of hydrochloric acid participating in the hydrolysis reaction is not too high, and black materials are easily generated due to too high acid concentration, wherein the delta H is-296 KJ/mol; the acid concentration is increased, the reaction speed is doubled, a large amount of heat is instantaneously released, and the temperature and the pressure in the kettle are increased too fast to control.

Disclosure of Invention

The invention aims to provide a preparation method of glyphosate technical, which solves the problem of over-quick local reaction in the background technology.

The purpose of the invention can be realized by the following technical scheme:

a preparation method of glyphosate technical comprises the following steps:

step A1, adding methanol, triethylamine, paraformaldehyde and glycine into a synthesis kettle for addition reaction, then adding dimethyl phosphite, and carrying out condensation reaction for 1-1.5h at 50 ℃ to obtain an intermediate product;

and step A2, after the reaction is finished, transferring the mixture into a hydrolysis kettle, introducing cooling water into a jacket, dropwise adding a hydrochloric acid solution with the mass fraction of 20% into the intermediate product, adding a phosphate ester amphoteric surfactant, keeping the temperature at 50 ℃ for 1h to obtain glyphosate raw drug, condensing the chloromethane generated in the hydrolysis process, then allowing the condensed methane to flow into a chloromethane production device, and allowing the condensed liquid to enter a methylal recovery process.

Further, in the step A1, the mass ratio of methanol, triethylamine, paraformaldehyde, glycine and dimethyl phosphite is 1: 4.3: 4.1: 4.9: 2.2.

further, the mass ratio of the intermediate product, the hydrochloric acid solution and the phosphate ester amphoteric surfactant in the step A2 is 1.2-1.5: 100: 9-11.

Wherein the phosphate ester amphoteric surfactant is prepared by the following steps:

step S11, weighing sodium dihydrogen phosphate aqueous solution which is prepared in advance and has the mass fraction of 40-50%, adding the sodium dihydrogen phosphate aqueous solution into a three-neck flask, placing epoxy chloropropane into a constant-pressure dropping funnel, adopting mechanical stirring, heating the epoxy chloropropane to 110 ℃ in an oil bath, dropping epichlorohydrin, controlling the dropping within 1h to be finished, reacting for 4h, removing solvent water by rotary evaporation after the reaction is finished, dissolving a product by ethanol, removing excessive sodium dihydrogen phosphate, recrystallizing a crude product by ethyl acetate and ethanol for 3-4 times, and drying the crude product in vacuum at 40 ℃ for 12h to obtain an intermediate 1;

the reaction process is as follows:

step S12, adding fatty acid into a three-neck flask, introducing nitrogen, heating to 120-130 ℃, slowly dripping N, N-dimethyl-1, 3-propanediamine by using a constant-pressure dropping funnel, controlling the dripping within half an hour to be finished, separating water generated by the reaction by using a water separator, continuing the reaction for 8 hours at 150 ℃, after the reaction is finished, carrying out reduced pressure distillation to obtain a light yellow crude product, recrystallizing for 3-4 times by using petroleum ether, and carrying out vacuum drying for 4 hours at 40-50 ℃ to obtain an intermediate 2;

the reaction process is as follows:

and step S13, adding the intermediate 1, the intermediate 2 and an ethanol solution with the mass fraction of 25% into a three-neck flask, and reacting at 85 ℃ for 8h to obtain the phosphate ester amphoteric surfactant.

The reaction process is as follows:

further, in the step S11, the molar ratio of sodium dihydrogen phosphate to epichlorohydrin is 1: 1.2.

further, in step S12, the molar ratio of N, N-dimethyl-1, 3-propanediamine to fatty acid is 1: 1.15.

further, in the step S13, the mass ratio of the intermediate 2 to the intermediate 1 to the ethanol solution is 1: 1: 15.4-20.2.

The invention has the beneficial effects that:

1) according to the invention, the phosphate ester amphoteric surfactant is added in the synthesis hydrolysis of glyphosate, and a relatively uniform environment can be formed after the phosphate ester amphoteric surfactant is added, so that the reaction is milder, and the occurrence of side reactions caused by over-quick local reaction can be prevented to a certain extent; in addition, bubbles generated in the reaction process form a small reaction environment, so that the reaction efficiency is improved, and the yield and the purity are further improved.

2) The phosphate ester amphoteric surfactant prepared by the invention contains a phosphoric acid structure in the structure, has good thermal stability and good temperature resistance in the later use process, contains a phosphoric acid group in the structure and has excellent alkali resistance, has good solubilization performance under the high-temperature and alkaline conditions of the synthesis process, has good biodegradability, and can be used for easily treating generated wastewater.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Preparation of phosphate ester amphoteric surfactant:

step S11, weighing sodium dihydrogen phosphate aqueous solution prepared in advance with mass fraction of 40%, adding the sodium dihydrogen phosphate aqueous solution into a three-neck flask, placing epoxy chloropropane into a constant-pressure dropping funnel, mechanically stirring, heating in an oil bath to 105 ℃, dropping epichlorohydrin, controlling the completion of dropping within 1h, reacting for 4h, removing solvent water after the reaction is finished, performing rotary evaporation, dissolving the product with ethanol, removing excessive sodium dihydrogen phosphate, recrystallizing the crude product with ethyl acetate and ethanol for 3 times, and performing vacuum drying at 40 ℃ for 12h to obtain an intermediate 1, wherein the molar ratio of the sodium dihydrogen phosphate to the epichlorohydrin is 1: 1.2;

step S12, adding fatty acid into a three-neck flask, introducing nitrogen, heating to 120 ℃, slowly dripping N, N-dimethyl-1, 3-propanediamine by using a constant-pressure dropping funnel, controlling the dripping within half an hour to be finished, separating water generated by the reaction by using a water separator, continuing the reaction for 8 hours at 150 ℃, after the reaction is finished, carrying out reduced pressure distillation to obtain a light yellow crude product, recrystallizing for 3 times by using petroleum ether, and carrying out vacuum drying for 4 hours at 40 ℃ to obtain an intermediate 2, wherein the molar ratio of the N, N-dimethyl-1, 3-propanediamine to the fatty acid is 1: 1.15;

step S13, adding the intermediate 1, the intermediate 2 and an ethanol solution with the mass fraction of 25% into a three-neck flask, and reacting at 85 ℃ for 8h to obtain the phosphate ester amphoteric surfactant, wherein the mass ratio of the intermediate 2 to the intermediate 1 to the ethanol solution is 1: 1: 15.4.

example 2

Preparation of phosphate ester amphoteric surfactant:

step S11, weighing a sodium dihydrogen phosphate aqueous solution prepared in advance with a mass fraction of 45%, adding the sodium dihydrogen phosphate aqueous solution into a three-neck flask, placing epoxy chloropropane into a constant-pressure dropping funnel, mechanically stirring, heating in an oil bath to 108 ℃, dropping epichlorohydrin, controlling the completion of dropping within 1h, reacting for 4h, after the reaction is finished, removing solvent water by rotary evaporation, dissolving the product with ethanol, removing excessive sodium dihydrogen phosphate, recrystallizing the crude product with ethyl acetate and ethanol for 3 times, and drying in vacuum at 40 ℃ for 12h to obtain an intermediate 1, wherein the molar ratio of the sodium dihydrogen phosphate to the epoxy chloropropane is 1: 1.2;

step S12, adding fatty acid into a three-neck flask, introducing nitrogen, heating to 125 ℃, slowly dripping N, N-dimethyl-1, 3-propanediamine by using a constant-pressure dropping funnel, controlling the dripping within half an hour to be finished, separating water generated by the reaction by using a water separator, continuing the reaction for 8 hours at 150 ℃, after the reaction is finished, carrying out reduced pressure distillation to obtain a light yellow crude product, recrystallizing for 3 times by using petroleum ether, and carrying out vacuum drying for 4 hours at 45 ℃ to obtain an intermediate 2, wherein the molar ratio of the N, N-dimethyl-1, 3-propanediamine to the fatty acid is 1: 1.15;

step S13, adding the intermediate 1, the intermediate 2 and an ethanol solution with the mass fraction of 25% into a three-neck flask, and reacting at 85 ℃ for 8h to obtain the phosphate ester amphoteric surfactant, wherein the mass ratio of the intermediate 2 to the intermediate 1 to the ethanol solution is 1: 1: 18.2.

example 3

Preparation of phosphate ester amphoteric surfactant:

step S11, weighing sodium dihydrogen phosphate aqueous solution which is prepared in advance and has the mass fraction of 50%, adding the sodium dihydrogen phosphate aqueous solution into a three-neck flask, placing epoxy chloropropane into a constant-pressure dropping funnel, mechanically stirring, heating the mixture to 110 ℃ in an oil bath, dropping epichlorohydrin, controlling the completion of dropping within 1h, reacting for 4h, removing solvent water after the reaction is finished, performing rotary evaporation, dissolving the product with ethanol, removing excessive sodium dihydrogen phosphate, recrystallizing the crude product with ethyl acetate and ethanol for 4 times, and performing vacuum drying at 40 ℃ for 12h to obtain an intermediate 1, wherein the molar ratio of the sodium dihydrogen phosphate to the epichlorohydrin is 1: 1.2;

step S12, adding fatty acid into a three-neck flask, introducing nitrogen, heating to 130 ℃, slowly dripping N, N-dimethyl-1, 3-propanediamine by using a constant-pressure dropping funnel, controlling the dripping within half an hour to be finished, separating water generated by the reaction by using a water separator, continuing the reaction for 8 hours at 150 ℃, after the reaction is finished, carrying out reduced pressure distillation to obtain a light yellow crude product, recrystallizing for 4 times by using petroleum ether, and carrying out vacuum drying for 4 hours at 50 ℃ to obtain an intermediate 2, wherein the molar ratio of the N, N-dimethyl-1, 3-propanediamine to the fatty acid is 1: 1.15;

step S13, adding the intermediate 1, the intermediate 2 and an ethanol solution with the mass fraction of 25% into a three-neck flask, and reacting at 85 ℃ for 8h to obtain the phosphate ester amphoteric surfactant, wherein the mass ratio of the intermediate 2 to the intermediate 1 to the ethanol solution is 1: 1: 20.2.

example 4

A preparation method of glyphosate technical comprises the following steps:

step A1, adding methanol, triethylamine, paraformaldehyde and glycine into a synthesis kettle for addition reaction, then adding dimethyl phosphite, and carrying out condensation reaction at 50 ℃ for 1h to obtain an intermediate product, wherein the mass ratio of methanol, triethylamine, paraformaldehyde, glycine and dimethyl phosphite is 1: 4.3: 4.1: 4.9: 2.2;

step A2, after the reaction is finished, transferring the mixture into a hydrolysis kettle, introducing cooling water into a jacket, dropwise adding a hydrochloric acid solution with the mass fraction of 20% into the intermediate product, adding the phosphate ester amphoteric surfactant prepared in example 1, keeping the temperature at 50 ℃ for 1h to obtain glyphosate raw drug, condensing chloromethane generated in the hydrolysis process, removing a chloromethane production device, and recovering condensed liquid noracetal, wherein the mass ratio of the intermediate product, the hydrochloric acid solution and the phosphate ester amphoteric surfactant is 1.2: 100: 9.

example 5

A preparation method of glyphosate technical comprises the following steps:

step A1, adding methanol, triethylamine, paraformaldehyde and glycine into a synthesis kettle for addition reaction, then adding dimethyl phosphite, and carrying out condensation reaction at 50 ℃ for 1h to obtain an intermediate product, wherein the mass ratio of methanol, triethylamine, paraformaldehyde, glycine and dimethyl phosphite is 1: 4.3: 4.1: 4.9: 2.2;

step A2, after the reaction is finished, transferring the mixture into a hydrolysis kettle, introducing cooling water into a jacket, dropwise adding a hydrochloric acid solution with the mass fraction of 20% into the intermediate product, adding the phosphate ester amphoteric surfactant prepared in example 2, keeping the temperature at 50 ℃ for 1h to obtain glyphosate raw drug, condensing chloromethane generated in the hydrolysis process, removing a chloromethane production device, and recovering condensed liquid noracetal, wherein the mass ratio of the intermediate product, the hydrochloric acid solution and the phosphate ester amphoteric surfactant is 1.3: 100: 10.

example 6

A preparation method of glyphosate technical comprises the following steps:

step A1, adding methanol, triethylamine, paraformaldehyde and glycine into a synthesis kettle for addition reaction, then adding dimethyl phosphite, and carrying out condensation reaction at 50 ℃ for 1.5h to obtain an intermediate product, wherein the mass ratio of the methanol to the triethylamine to the paraformaldehyde to the glycine to the dimethyl phosphite is 1: 4.3: 4.1: 4.9: 2.2;

step A2, after the reaction is finished, transferring the mixture into a hydrolysis kettle, introducing cooling water into a jacket, dropwise adding a hydrochloric acid solution with the mass fraction of 20% into the intermediate product, adding the phosphate ester amphoteric surfactant prepared in example 3, keeping the temperature at 50 ℃ for 1h to obtain glyphosate raw drug, condensing chloromethane generated in the hydrolysis process, removing a chloromethane production device, and recovering condensed liquid noracetal, wherein the mass ratio of the intermediate product, the hydrochloric acid solution and the phosphate ester amphoteric surfactant is 1.5: 100: 11.

comparative example 1

75g of glycine and 160g of phosphorous acid are dissolved in 400g of methanol and stirred for 60min at normal temperature for later use. Putting 246g of 36.5 mass percent formaldehyde, 98g of 50 mass percent sulfuric acid and 600g of methanol into a high-pressure reaction kettle, heating to 70-75 ℃ while stirring, slowly adding glycine phosphorous acid solution, sealing the reaction kettle after adding, slowly heating to 180 ℃, controlling the pressure to be 10MPa, reacting for 10 hours, cooling after finishing heat preservation, adding a small amount of liquid alkali, adjusting the pH value of the system to 1-1.5, and separating out a large amount of solids during the reaction to obtain 138.1g of glyphosate raw drug.

The glyphosate technical obtained in examples 4-6 and comparative example 1 is tested for yield and purity, and the test results are shown in table 1:

TABLE 1

Item	Example 4	Example 5	Example 6	Comparative example 1
					Yield%	93.21	93.91	92.86	78.8
Purity%	99.46	99.65	99.57	95.1

As can be seen from table 1, the glyphosate technical prepared in examples 4 to 6 has a yield of 92.86 to 93.91% and a purity of 99% compared with comparative example 1.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.