Method for circularly producing refined glufosinate ammonium salt in organic solvent
By optimizing the reaction conditions and cyclic production methods, the problems of insufficient solubility and long production cycle of purified glufosinate hydrochloride in organic solvents are solved, efficient production and complete recycling of organic solvents are achieved, and yield and Resource utilization rate reduces environmental pollution.
Patent Information
- Application Number
- CN202411461394.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-18
- Publication Date
- 2025-01-14
AI Technical Summary
In the prior art, the solubility of the purified glufosinate hydrochloride in organic solvents is limited, resulting in incomplete reactions, low yields, long production cycles, and incomplete recovery of organic solvents leads to waste of resources and environmental pollution.
By optimizing the reaction conditions and solvent system, using a cyclic production method, using alcohol solvents and ammonia gas for ammonia reaction, and combining with under-pressure distillation to recover the organic solvent, the efficient production of refined glufosinate ammonium salt and the complete recycling of organic solvents are achieved.
The yield of refined glufosinate ammonium salt is improved, the production cycle is shortened, the complete recycling of organic solvents is achieved, the production cost and environmental pollution are reduced, and the resource utilization and environmental compatibility are improved.
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Figure CN119306758A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a method for cyclically producing refined glufosinate ammonium salt in an organic solvent, and mainly relates to the field of organic chemical synthesis and the technical field of pesticide production. Background Art
[0002] Glufosinate is a broad-spectrum, highly effective systemic herbicide widely used in farmland, orchards, gardens and other fields. Its ammonium salt form has become one of the main formulations of glufosinate due to its better water solubility and environmental compatibility. In the field of pesticide production, organic solvent recycling technology has gradually gained attention, which can not only reduce production costs, but also reduce environmental pollution.
[0003] Solution of the prior art: In the prior art, an organic solvent such as methanol is usually used as a reaction medium to react refined glufosinate hydrochloride with ammonia at a certain temperature to generate refined glufosinate ammonium salt. The mother liquor after the reaction usually contains unreacted glufosinate hydrochloride, methanol and ammonia, and the methanol and ammonia can be recovered by vacuum distillation and recycled.
[0004] Problems with the prior art: However, the prior art still has some problems in practical applications. First, due to the limited solubility of refined glufosinate-ammonium hydrochloride in organic solvents, the reaction is incomplete and the yield is not high. Secondly, the prior art usually requires repeated reactions and vacuum distillation processes, which not only increases production costs but also prolongs the production cycle. In addition, the prior art often cannot fully recycle methanol and ammonia when recovering them, resulting in waste of resources and environmental pollution. Therefore, how to improve the yield of refined glufosinate-ammonium ammonium salt, shorten the production cycle, and achieve complete recycling of organic solvents is an important problem facing the current technology. Summary of the invention
[0005] A method for cyclically producing refined glufosinate ammonium salt in an organic solvent: Compared with the prior art, this technical solution mainly solves: Improve the yield of refined glufosinate ammonium salt: Due to the limited solubility of refined glufosinate ammonium hydrochloride in organic solvents, the reaction is incomplete and the yield is not high. This technical solution improves the yield of refined glufosinate ammonium salt by optimizing the reaction conditions and solvent system.
[0006] Shorten the production cycle: The existing technology usually requires repeated reactions and vacuum distillation processes, which not only increases production costs but also prolongs the production cycle. This technical solution reduces the number of reactions and shortens the production cycle through a cyclic production method.
[0007] Achieve complete recycling of organic solvents: Existing technologies often fail to completely recycle methanol and ammonia, resulting in waste of resources and environmental pollution. This technical solution achieves complete recycling of organic solvents through the method of reduced pressure distillation, reducing waste of resources and environmental pollution.
[0008] In order to achieve the above object, the technical solution of the present invention is: A method for cyclically producing refined glufosinate ammonium salt in an organic solvent, the reaction formula is: , this technical solution mainly adopts the following technical means: (1) After the refined glufosinate hydrochloride is mixed with an alcohol solvent, ammonia gas is introduced to carry out an amination reaction to obtain refined glufosinate ammonium salt and a mother liquor 1; (2) Mother liquor 1 is subjected to reduced pressure distillation to recover alcohol solvent and ammonium chloride, and mother liquor 2 is obtained by collecting after distillation; (3) the mother liquor 2, the refined glufosinate hydrochloride and the alcohol solvent recovered in step (2) are mixed, and ammonia gas is introduced to carry out an amination reaction to obtain the refined glufosinate ammonium salt and the mother liquor 3; (4) Mother liquor 3 is subjected to reduced pressure distillation to recover alcohol solvent and ammonium chloride, and mother liquor 4 is obtained by collecting after distillation; (5) Repeat steps (3) and (4) to continuously produce refined glufosinate ammonium salt.
[0009] The reaction formula is as follows:
[0010] The alcohol solvent described in step (1) is selected from one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and tert-butanol.
[0011] During the amination reaction in step (1), a certain amount of ammonium salt is added, and the ammonium salt is selected from one or more of ammonium chloride, ammonium carbonate, ammonium bicarbonate, ammonium oxalate, ammonium sulfate, and ammonium nitrate.
[0012] The amount of the ammonium salt added is 0.5-5wt%, and the ammonium salt is added in a manner of mixing with an alcohol solvent. Adding the ammonium salt facilitates the crystallization of the refined glufosinate ammonium salt and shortens the crystallization time.
[0013] In steps (1) and (3), ammonia gas is introduced at -10-5°C and kept warm for 0.5-1h, then the temperature is raised to 50-60°C for amination reaction. The amination reaction time is 4-6h.
[0014] In steps (2) and (4), the reduced pressure distillation temperature is 60-80° C. and the distillation pressure is 10-80 KPa.
[0015] Technical Effects Due to the advanced nature of the technical solution, it can be widely used in the fields of pesticide production technology, organic chemical synthesis, solvent recycling and other application fields.
[0016] 1. This technical solution provides a novel method for producing refined glufosinate ammonium salt. By optimizing reaction conditions and recycling organic solvents, it can not only improve the yield of L-glufosinate ammonium salt and shorten the production cycle to 4-6h (L-glufosinate ammonium salt has a high yield and has almost completely precipitated, achieving a shortened cycle), but also achieve complete recycling of organic solvents, thereby reducing production costs and improving economic benefits. In addition, since glufosinate ammonium salt has better water solubility and environmental compatibility, the promotion and application of this technical solution helps to improve the overall quality and safety of pesticides.
[0017] 2. This technical solution provides an efficient synthesis method. By optimizing reaction conditions and recycling organic solvents, the synthesis efficiency can be improved, the reaction cycle can be shortened, and the organic solvent can be completely recycled, thereby reducing the synthesis cost and improving the economic benefits. In addition, since the organic solvent used in this technical solution is methanol, which is a common and environmentally friendly organic solvent, the promotion and application of this technical solution will help promote the green development of organic chemical synthesis.
[0018] 3. This technical solution provides an effective solvent recycling method. By recovering methanol and ammonia through vacuum distillation and recycling them, it can not only achieve complete recycling of organic solvents and reduce resource waste, but also reduce environmental pollution. Therefore, the promotion and application of this technical solution will help promote the development of solvent recycling technology and promote sustainable development. In general, the promotion and application of this technical solution is expected to play an important role in the fields of pesticide production technology, organic chemical synthesis, and solvent recycling, meet market demand, and promote technological progress and sustainable development in related fields. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION
[0020] Example 1 Step 1: Add 0.5wt% ammonium chloride to 500g methanol, then add 100g of glufosinate hydrochloride, add 35g of ammonia gas, and keep warm at 60°C for 10min to precipitate a white solid. After keeping warm at 60°C for 4h, centrifuge the reactant to obtain 90g of glufosinate ammonium salt (purity 99%, yield 98.5%) and 510g of mother liquor 1.
[0021] Step 2: Mother liquor 1 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 155 g of methanol and 23.5 g of ammonium chloride (purity 99%, yield 97.4%) were collected. After the distillation was completed, 331 g of mother liquor 2 remained.
[0022] Step 3: Add 100 g of refined glufosinate hydrochloride, 0.5 wt% ammonium chloride and 155 g of methanol distilled under reduced pressure in the previous step to the mother liquor 2, add 35 g of ammonia gas, and keep warm at 60° C. for 4 hours. After the insulation, the reactant is centrifuged to obtain 90.2 g of refined glufosinate ammonium salt (purity 99%, yield 98.5%) and 506 g of mother liquor 3.
[0023] Step 4: Mother liquor 3 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 151 g of methanol and 23.3 g of ammonium chloride (purity 99%, yield 96.5%) were collected. After the distillation was completed, 323 g of mother liquor 4 remained.
[0024] Step 5: Repeat steps 3 and 4 to continuously cycle and produce refined glufosinate ammonium salt. Each cycle can produce about 90 g of refined glufosinate ammonium salt (purity 99%, yield 98%) and 503 g of mother liquor 4. The product can be recycled for more than 15 batches and still maintain high purity and high yield.
[0025] Embodiment 2: Step 1: 100 g of refined glufosinate hydrochloride was mixed with 500 g of methanol, 35 g of ammonia gas was added, and the mixture was incubated at 60°C for 3 h to precipitate a white solid. After incubation for 4 h, the reaction solution was centrifuged to obtain 75 g of refined glufosinate ammonium salt (purity 99%, yield 82%) and 520 g of mother liquor 1.
[0026] Step 2: Mother liquor 1 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 152 g of methanol and 21 g of ammonium chloride (purity 99%, yield 87%) were collected. After the distillation was completed, 339 g of mother liquor 2 remained.
[0027] Step 3: Add 100 g of refined glufosinate hydrochloride and 152 g of methanol distilled under reduced pressure in the previous step to the mother liquor 2, add 35 g of ammonia gas, and keep warm at 60° C. for 4 hours. After the insulation, the reactant is centrifuged to obtain 74 g of refined glufosinate ammonium salt (purity 96%, yield 81%) and 519 g of mother liquor 3.
[0028] Step 4: Mother liquor 3 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 149 g of methanol and 20.8 g of ammonium chloride (purity 99%, yield 86%) were collected. After the distillation was completed, 334 g of mother liquor 4 remained.
[0029] Step 5: Repeat steps 3 and 4 to continuously cycle and produce refined glufosinate ammonium salt. Each cycle can produce about 72 grams of refined glufosinate ammonium salt (yield 79%) and about 525 grams of mother liquor 4. The purity of refined glufosinate ammonium salt decreases with the increase of the cycle batches, and decreases by 1-3% per cycle batch, and the maximum cycle batch is 3-5 batches.
[0030] Embodiment 3: Step 1: 100 g of refined glufosinate hydrochloride was mixed with 500 g of methanol, 35 g of ammonia gas was added, and the mixture was incubated at 60°C for 3 h to precipitate a white solid. After incubation for 16 h, the reactant was centrifuged to obtain 89.5 g of refined glufosinate ammonium salt (purity 99%, yield 98%) and 508 g of mother liquor 1.
[0031] Step 2: Mother liquor 1 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 151 g of methanol and 22 g of ammonium chloride (purity 99%, yield 91%) were collected. After the distillation was completed, 327 g of mother liquor 2 remained.
[0032] Step 3: Add 100 g of refined glufosinate hydrochloride and 151 g of methanol distilled under reduced pressure in the previous step to the mother liquor 2, add 35 g of ammonia gas, and keep warm at 60° C. for 16 hours. After the insulation, the reactant is centrifuged to obtain 88 g of refined glufosinate ammonium salt (purity 98%, yield 96%) and 519 g of mother liquor 3.
[0033] Step 4: Mother liquor 3 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 146 g of methanol and 22.6 g of ammonium chloride (purity 99%, yield 93%) were collected. After the distillation was completed, 336 g of mother liquor 4 remained.
[0034] Step 5: Repeat steps 3 and 4 to continuously cycle and produce refined glufosinate ammonium salt. Each cycle can produce 86 g of refined glufosinate ammonium salt (yield 94%) and 515 g of mother liquor 4. The purity of refined glufosinate ammonium salt decreases with the increase of the cycle batches, and the purity decreases by 0.5-1% per cycle batch, and the maximum cycle batch is 5-8 batches.
[0035] Embodiment 4: Step 1: Add 0.5wt% ammonium nitrate to 500g methanol, then add 100g of refined glufosinate hydrochloride, add 35g of ammonia gas, and keep warm at 60°C for 15min to precipitate a white solid. After keeping warm at 60°C for 4h, centrifuge the reactant to obtain 89.8g of refined glufosinate ammonium salt (purity 99%, yield 98.3%) and 522g of mother liquor 1.
[0036] Step 2: Mother liquor 1 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 142 g of methanol and 22.9 g of ammonium chloride (purity 99%, yield 95%) were collected. After the distillation was completed, 341 g of mother liquor 2 remained.
[0037] Step 3: Add 100 g of refined glufosinate hydrochloride, 0.5 wt% ammonium nitrate and 142 g of methanol distilled under reduced pressure in the previous step to the mother liquor 2, add 35 g of ammonia gas, and keep warm at 60° C. for 4 hours. After the insulation is completed, the reactant is centrifuged to obtain 90 g of refined glufosinate ammonium salt (purity 98.5%, yield 98.5%) and 518 g of mother liquor 3.
[0038] Step 4: Mother liquor 3 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 144 g of methanol and 22.7 g of ammonium chloride (purity 98.2%, yield 94%) were collected. After the distillation was completed, 335 g of mother liquor 4 remained.
[0039] Step 5: Repeat steps 3 and 4 to continuously cycle and produce refined glufosinate ammonium salt. Each cycle can produce about 88.5 g of refined glufosinate ammonium salt (purity 98%, yield 97%) and 515 g of mother liquor 4. The product can be recycled for more than 12 batches and still maintain high purity and high yield.
[0040] Embodiment 5: Step 1: Add 1wt% ammonium chloride and 1wt% ammonium sulfate to 500g methanol, then add 100g of refined glufosinate hydrochloride, add 35g of ammonia gas, and keep warm at 60°C for 9min to precipitate a white solid. After keeping warm at 60°C for 4h, the reactant is centrifuged to obtain 90.2g of refined glufosinate ammonium salt (purity 98.8%, yield 98.6%) and 506g of mother liquor 1.
[0041] Step 2: Mother liquor 1 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 158 g of methanol and 23.7 g of ammonium chloride (purity 99%, yield 98%) were collected. After the distillation was completed, 319 g of mother liquor 2 remained.
[0042] Step 3: Add 100g of refined glufosinate hydrochloride, 1wt% ammonium chloride, 1wt% ammonium sulfate and 158g of methanol distilled under reduced pressure in the previous step to the mother liquor 2, add 35g of ammonia gas, and keep warm at 60°C for 4 hours. After the insulation, the reactant is centrifuged to obtain 89.9g of refined glufosinate ammonium salt (purity 98.4%, yield 98.2%) and 501g of mother liquor 3.
[0043] Step 4: Mother liquor 3 was distilled under reduced pressure, with a distillation pressure of 50 kPa and a distillation temperature of 60° C. During the distillation process, 160 g of methanol and 23.1 g of ammonium chloride (purity 98.5%, yield 95.5%) were collected. After the distillation was completed, 314 g of mother liquor 4 remained.
[0044] Step 5: Repeat steps 3 and 4 to continuously cycle and produce refined glufosinate ammonium salt. Each cycle can produce about 87.8 g of refined glufosinate ammonium salt (purity 98%, yield 96%) and 495 g of mother liquor 4. The product can be recycled for more than 10 batches and still maintain high purity and high yield.
[0045] Compared with the existing technology, the beneficial effects of this technical solution are as follows: 1. Improve the yield: The present invention adopts a new reaction method, and improves the yield of glufosinate ammonium salt by cyclically producing the refined glufosinate ammonium salt in an organic solvent. Due to the new reaction method, the ammonium salt is added in advance, so that the solubility of the refined glufosinate ammonium hydrochloride in the organic solvent is improved, and it is easier to precipitate, so that the reaction is continuously carried out in a positive direction, thereby improving the completeness of the reaction and further improving the yield.
[0046] 2. Shorten the production cycle: The present invention adopts a cyclic production method, through repeated reaction and vacuum distillation process, adding ammonium salt makes the product refined glufosinate ammonium salt crystallize more quickly, greatly shortening the production cycle. Due to the use of the cyclic production method, the reaction and vacuum distillation time are reduced, thereby shortening the production cycle and improving production efficiency.
[0047] 3. Complete recycling of organic solvents: The present invention adopts a method for recycling organic solvents, recovering methanol by vacuum distillation and recycling it. Due to the adoption of the method for recycling organic solvents, complete recycling of organic solvents is achieved, which not only reduces production costs but also reduces environmental pollution.
[0048] 4. Improve resource utilization: The present invention adopts a method for recovering methanol and ammonia, wherein methanol is recovered by vacuum distillation and ammonia is retained in the mother liquor for recycling. Due to the method for recovering methanol and ammonia, resource utilization is improved and waste of resources is reduced.
[0049] 5. Improve environmental compatibility: The present invention adopts a refined glufosinate in the form of an ammonium salt. Due to its better water solubility and environmental compatibility, the environmental compatibility of the ammonium salt of refined glufosinate is improved, and the negative impact on the environment is reduced.
Claims
1. A method for cyclically producing refined glufosinate ammonium salt in an organic solvent, characterized in that: The steps include: (1) After the refined glufosinate hydrochloride is mixed with an alcohol solvent, ammonia gas is introduced to carry out an amination reaction to obtain refined glufosinate ammonium salt and a mother liquor 1; (2) Mother liquor 1 is subjected to reduced pressure distillation to recover the alcohol solvent and ammonium chloride, and mother liquor 2 is obtained by collecting after distillation; (3) the mother liquor 2, the refined glufosinate hydrochloride and the alcohol solvent recovered in step (2) are mixed, and ammonia gas is introduced to carry out an amination reaction to obtain the refined glufosinate ammonium salt and the mother liquor 3; (4) Mother liquor 3 is subjected to reduced pressure distillation to recover alcohol solvent and ammonium chloride, and mother liquor 4 is obtained by collecting after distillation; (5) Repeat steps (3) and (4) to continuously produce refined glufosinate ammonium salt.
2. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: The alcohol solvent described in step (1) is selected from one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and tert-butanol.
3. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: In steps (1) and (3), ammonia gas is introduced at -10-5°C and kept warm for 0.5-1h, then the temperature is raised to 50-60°C for amination reaction. The amination reaction time is 1-4h.
4. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: In steps (2) and (4), the reduced pressure distillation temperature is 60-80° C. and the distillation pressure is 10-80 KPa.
5. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: In step (3) and the circulation process, the mother liquor 2 is subjected to an amination reaction at a volume fraction of 50-100%.
6. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: During the amination reaction in step (1), a certain amount of ammonium salt is added, and the ammonium salt is selected from one or more of ammonium chloride, ammonium carbonate, ammonium bicarbonate, ammonium oxalate, ammonium sulfate, and ammonium nitrate.
7. The method for cyclically producing refined glufosinate ammonium salt in an organic solvent according to claim 1, characterized in that: The added amount of the ammonium salt is 0.5-5wt%, and the ammonium salt is added in a manner of being mixed with an alcohol solvent.