Production process of 2-chlorophenylglycine
By extracting and back-extracting o-chlorophenylglycine wastewater, the problem of product loss in wastewater was solved, the process yield was improved, and the production cost was reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIUJIANG ZHONGXING MEDICINE & CHEM CO LTD
- Filing Date
- 2025-07-09
- Publication Date
- 2026-05-12
AI Technical Summary
In the existing o-chlorophenylglycine production process, the product yield is low, with about 10-15% of the product lost in wastewater, resulting in a low yield.
A novel extractant was used to extract the product from the wastewater, and the extractant phase was used for back-extraction to obtain a sulfuric acid solution containing the product, which was then used for process neutralization to improve the process yield.
Using this method, the yield of the process route is increased to over 85%, the extract phase can be repeatedly recycled without increasing production costs, and the loss of the extract phase is minimal.
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Figure CN122010755A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of organic wastewater treatment technology, specifically to a process for producing o-chlorophenylglycine and a method for treating its wastewater. Background Technology
[0002] o-Chlorophenylglycine is an important intermediate for clopidogrel, a drug used to prevent and treat cardiovascular, cerebrovascular, and other circulatory disorders caused by platelet hyperaggregation. Although there are various synthetic routes for its preparation, most industrial applications currently use the Bucherer-Bergs method. Referring to patents such as CN 101058547A, CN105237421A, and CN11468530A, o-chlorophenylbenzaldehyde, ammonium bicarbonate, and sodium cyanide are used as raw materials to first cyclize o-chlorophenylhydantoin, then perform alkaline hydrolysis, and finally acidify to obtain o-chlorophenylglycine. The process route is shown in Formula 1.
[0003]
[0004] Formula 1 Bucherer-Bergs method for the preparation of o-chlorophenylglycine This process route boasts stable product quality and good economic benefits; however, its yield is only 70-75%, which is considered low. Through full-process HPLC control and material balance calculations, the analysis revealed that the main reason for the low yield is that approximately 10-15% of the product, o-chlorophenylglycine, dissolves in the centrifugal wastewater. The production process generates approximately 10 tons of wastewater per ton of product, with the product loss in the wastewater accounting for 10-15% of the theoretical yield, consistent with the HPLC control results and material balance calculations. Therefore, effectively recovering the product from the o-chlorophenylglycine wastewater is the most direct way to improve the process yield. Summary of the Invention
[0005] To address the problems existing in the prior art, the first aspect of this invention proposes a process for producing o-chlorophenylglycine, comprising, Step 1: After mixing the alkali, alcohol, and sodium cyanide, o-chlorobenzaldehyde is added and the temperature is controlled to obtain the first mixture; Step 2: Mix the first mixture, water, and alkali, and control the temperature to obtain the second mixture; Step 3: The second mixture is added to activated carbon for adsorption and separation to obtain an aqueous phase system; Step 4: Adjust the pH of the aqueous system; Step 5: Temperature-controlled crystallization to obtain the finished product o-chlorophenylglycine, and o-chlorophenylglycine wastewater B; Step 6: Use the extractant phase to extract o-chlorophenylglycine wastewater B to obtain the upper loaded extractant phase and the lower raffinate. Step 7: Add acid to the upper loaded extract phase to obtain neutralized acid water layer A and regenerated extract phase.
[0006] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the neutralized acidic water layer A obtained in step 7 is used to adjust the pH of the aqueous phase system in step 4.
[0007] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the regenerated extract phase obtained in step 7 is used as the extract phase in step 6 to extract the o-chlorophenylglycine wastewater B in step 6, so as to obtain an upper loaded extract phase and a lower raffinate.
[0008] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the alcohol in step 1 is selected from any one or a mixture of methanol, ethanol, and isopropanol.
[0009] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the alkali in step 1 is selected from any or a combination of sodium hydroxide, sodium tert-butoxide, potassium tert-butoxide, and ammonium bicarbonate.
[0010] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of alkali added to each 1 kg of alcohol in step 1 is 500~800g. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of alkali added to each 1 kg of alcohol in step 1 is optionally 600g, 650g, 700g, 750g, or 800g.
[0011] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of sodium cyanide added to each 1 kg of alcohol in step 1 is 400~750g. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of sodium cyanide added to each 1 kg of alcohol in step 1 is optionally 450g, 500g, 550g, 600g, 650g, or 700g.
[0012] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of o-chlorobenzaldehyde added to each 1 kg of alcohol in step 1 is 400~600g. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of o-chlorobenzaldehyde added to each 1 kg of alcohol in step 1 is optionally 450g, 500g, 550g, or 600g.
[0013] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature control method in step 1 is to control the temperature to 50~70℃. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature control method in step 1 can be optionally controlled to 50℃, 55℃, 60℃, 65℃, or 70℃.
[0014] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of liquid alkali added to each 1L of water in step 2 is 1.0~2.0kg. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass of liquid alkali added to each 1L of water in step 2 is optionally 1.2kg, 1.4kg, 1.6kg, or 1.8kg.
[0015] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature control method is to control the temperature to 120~160℃. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature control method can be optionally controlled to 130℃, 140℃, 150℃, or 160℃.
[0016] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the pH of the aqueous phase system is adjusted to 6.5~7.0 in step 4. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the pH of the aqueous phase system is optionally adjusted to 6.6, 6.7, 6.8, or 6.9 in step 4.
[0017] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature-controlled crystallization method in step 5 is to control the temperature to 20~30℃ for crystallization. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the temperature-controlled crystallization method in step 5 can be optionally controlled to 22℃, 24℃, 26℃, or 28℃.
[0018] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mixing volume ratio of the extract phase and o-chlorophenylglycine wastewater B in step 6 is 1:(8~12). In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mixing volume ratio of the extract phase and o-chlorophenylglycine wastewater B in step 6 is optionally 1:9, 1:10, or 1:11.
[0019] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the extraction temperature in step 6 is 20~35℃. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the extraction temperature in step 6 can be selected as 22℃, 24℃, 26℃, 28℃, 30℃, or 32℃.
[0020] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass fraction of o-chlorophenylglycine in the o-chlorophenylglycine wastewater B is 1~2wt%. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass fraction of o-chlorophenylglycine in the o-chlorophenylglycine wastewater B is optionally 1.2wt%, 1.4wt%, 1.6wt%, or 1.8wt%.
[0021] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the acid in step 7 is selected from one or more of sulfuric acid, hydrochloric acid, and nitric acid.
[0022] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass fraction of the acid is 15-25%, and in some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the mass fraction of the acid is optionally 17%, 19%, 21%, or 23%.
[0023] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, in step 4, the pH of the aqueous phase system in step 4 is adjusted to 6.5~7.0 using neutralizing acid water layer A. In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the pH of the aqueous phase system in step 4 is optionally adjusted to 6.6, 6.7, 6.8, or 6.9 using neutralizing acid water layer A.
[0024] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the diluent includes one or more of sulfonated kerosene, cyclohexane, and n-octanol.
[0025] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the extraction ternary mixture includes a first extractant, a second extractant, and a third extractant, wherein the first extractant, the second extractant, and the third extractant are each independently selected from one or more of bis(2-ethylhexyl) phosphate, (benzyl)phosphonate monophenyl ester, 4-methyl-3-penten-2-one oxime, dioctyl phthalate, 5-dodecyl-2-hydroxybenzaldehyde oxime, and tributyl phosphate.
[0026] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the volume ratio of sulfonated kerosene and cyclohexane in the diluent is (1~4):1.
[0027] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the molar ratio of the first extractant and the second extractant in the ternary extraction mixture is (8~12):(1~3).
[0028] In some specific embodiments of the o-chlorophenylglycine production process proposed in the first aspect, the molar ratio of the second extractant and the third extractant in the ternary extraction mixture is (1~3):(5~9).
[0029] The reagents used in this invention are all purchased from the open and legal market and have not undergone further purification.
[0030] In some embodiments of the present invention, the room temperature is 5~45°C, in some embodiments, the room temperature is 10~40°C, in some embodiments, the room temperature is 15~35°C, in some embodiments, the room temperature is 20~30°C, and in some embodiments, the room temperature is 25°C.
[0031] Advantages of this invention: This invention addresses the shortcomings of existing processes, such as low yield and significant product loss in wastewater. It employs a novel extractant to effectively extract the product from the wastewater. The extracted solution containing the product is then back-eluted with dilute sulfuric acid to obtain a sulfuric acid solution containing the product. This solution is used for process neutralization. This technology increases the yield of the process to over 85%, and the extracted phase can be experimentally recycled without increasing production costs. The loss of the extracted phase during multiple cycles is minimal, resulting in low recycling costs. Attached Figure Description
[0032] Figure 1 This invention presents a process flow diagram; Detailed Implementation
[0033] To enable those skilled in the art to better understand the technical solutions of the present invention, some non-limiting embodiments are further disclosed below to provide a more detailed description of the present invention.
[0034] This invention is achieved through the following technical solution: Using o-chlorobenzaldehyde, ammonium bicarbonate and sodium cyanide as raw materials, and water and methanol as solvents, o-chlorophenylglycine is obtained through cyanidation, hydrolysis, decolorization, neutralization and centrifugation, along with wastewater containing o-chlorophenylglycine.
[0035] The wastewater is repeatedly extracted using an extractant to extract all the product from the wastewater into the extract, and then sulfuric acid is used to back-extract the extract.
[0036] Example 1 The ternary extraction mixture consists of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate, CAS: 298-07-7), 15 parts by mass of the second extractant ((benzyl)phosphonate monophenyl ester, CAS: 59447-21-1), and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime, CAS: 28052-09-7).
[0037] The ternary extraction mixture was dissolved at a concentration of 120 g / L in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) to prepare the extraction phase OP-1.
[0038] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the first extractant (bis(2-ethylhexyl) phosphate) is not added, and only the second extractant ((benzyl)phosphonate monophenyl ester) and the third extractant (4-methyl-3-penten-2-one oxime) are added, as follows: A mixture of 15 parts by mass of the second extractant ((benzyl)phosphonic acid monophenyl ester) and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime) was prepared by dissolving the mixture at a concentration of 120 g / L in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) to form the extract phase OP-2.
[0039] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the second extractant ((benzyl)phosphonate monophenyl ester) is not added; only the first extractant (bis(2-ethylhexyl) phosphate) and the third extractant (4-methyl-3-penten-2-one oxime) are added, as follows: A mixture of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate) and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime) was prepared by dissolving the mixture at a concentration of 120 g / L in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) to form the extract phase OP-3.
[0040] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the third extractant (4-methyl-3-penten-2-one oxime) is not added; only the first extractant (bis(2-ethylhexyl) phosphate) and the second extractant ((benzyl)phosphonate monophenyl ester) are added, specifically as follows: A mixture of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate) and 15 parts by mass of the second extractant ((benzyl)phosphonate monophenyl ester) was prepared by dissolving the mixture at a concentration of 120 g / L in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) to form the extract phase OP-4.
[0041] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the first extractant (bis(2-ethylhexyl) phosphate) was replaced with an equal mass of dioctyl phthalate (CAS: 117-84-0), specifically as follows: A mixture consisting of 50 parts by mass of the first extractant (dioctyl phthalate), 15 parts by mass of the second extractant ((benzyl)phosphonate monophenyl ester), and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime) was dissolved in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) at a concentration of 120 g / L to prepare the extract phase OP-5.
[0042] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the second extractant was replaced by an equal mass of tributyl phosphate (TBP, CAS: 126-73-8), specifically as follows: A mixture consisting of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate), 15 parts by mass of the second extractant (tributyl phosphate (TBP), and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime) was dissolved in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) at a concentration of 120 g / L to prepare the extract phase OP-6.
[0043] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that the third extractant (4-methyl-3-penten-2-one oxime) was replaced with an equal mass of 5-dodecyl-2-hydroxybenzaldehyde oxime (LIX-860, CAS: 77635-32-6), specifically as follows: A mixture consisting of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate), 15 parts by mass of the second extractant ((benzyl)phosphonate monophenyl ester), and 35 parts by mass of the third extractant 5-dodecyl-2-hydroxybenzaldehyde oxime was prepared by dissolving the mixture at a concentration of 120 g / L in a mixed solvent of sulfonated kerosene and cyclohexane (V:V=2:1) to prepare the extract phase OP-7.
[0044] Comparative Example 7 The ternary extraction mixture consists of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate), 15 parts by mass of the second extractant ((benzyl)phosphonic acid monophenyl ester), and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime).
[0045] The ternary mixture was dissolved in sulfonated kerosene at a concentration of 120 g / L to prepare the extract phase OP-8.
[0046] Comparative Example 8 The ternary extraction mixture consists of 50 parts by mass of the first extractant (bis(2-ethylhexyl) phosphate), 15 parts by mass of the second extractant ((benzyl)phosphonic acid monophenyl ester), and 35 parts by mass of the third extractant (4-methyl-3-penten-2-one oxime).
[0047] The ternary mixture was dissolved in cyclohexane at a concentration of 120 g / L to prepare the extract phase OP-9.
[0048] Comparative Example 9 (without sulfonated kerosene) A mixture of sulfonated kerosene and cyclohexane at a volume ratio of 2:1 was used as the extraction phase OP-10.
[0049] Example 2: Extraction of o-chlorophenylglycine wastewater: like Figure 1 As shown, the steps of the present invention include: Cyanidation step 1: Add 30.0 g ammonium bicarbonate, 40.0 g methanol, and 26.0 g of 30% sodium cyanide sequentially to a flask. Stir the system in a sealed container for 0.5 h. Add 20.0 g of o-chlorobenzaldehyde to the system and heat to 65°C and maintain the temperature for 5 h. After the isothermal period, use a distillation apparatus to heat to 102°C to recover methanol and remove ammonia.
[0050] Hydrolysis step 2: After the recovery of methanol and the removal of ammonia are completed, add 40.0g of water and 80.8g of 32% sodium hydroxide aqueous solution, start heating to 140℃, and carry out hydrolysis reaction in a sealed environment for 4 hours.
[0051] Decolorization step 3: After hydrolysis, the system is heated to 105°C to remove ammonia. After ammonia removal, the temperature is lowered to 80~85°C, 4g of activated carbon is added, and the system is kept warm for decolorization for 30min. The activated carbon is removed by centrifugation to obtain an aqueous system.
[0052] Neutralization step 4: After decolorization, the neutralized acid aqueous layer A obtained from back-extraction step-2 is used as the neutralizing acid to adjust the pH of the aqueous phase system to 6.5~7.0. After stirring for 10 minutes, the pH is retested and found to be qualified.
[0053] Crystallization step 5: After pH adjustment, cool to 25°C and stir for 1 hour to crystallize. After pH is retested and found to be qualified, filter, wash the filter cake with water, dry it, and dry the filter cake at 85°C to obtain the product o-chlorophenylglycine with a yield of %. The filtrate is used as o-chlorophenylglycine wastewater B for extraction step-1.
[0054] Extraction Step 1: Add 200 mL of o-chlorophenylglycine wastewater B (containing 1.5 wt% o-chlorophenylglycine) to the flask, control the system temperature at 25~35°C, add 20 mL of extraction phase (any one of OP-1~OP-10) to the system, stir the system at 25~35°C for 2 h, after the reaction is complete, let it stand and separate the layers, separate the upper loaded extraction phase, continue to add 20 mL of extraction phase (any one of OP-1~OP-10) to the o-chlorophenylglycine wastewater, stir the system at 25~35°C for 2 h, after the reaction is complete, let it stand and separate the layers, separate the upper loaded extraction phase and the lower raffinate, combine the two upper loaded extraction phases, and collect the lower raffinate, treat it to meet the standards and then discharge it.
[0055] Back-extraction step-2: Add 10 mL of 20% dilute sulfuric acid to the combined upper loaded extract phase. Stir the system at 25~35℃ for 2 h. After the reaction is complete, allow it to stand and separate into layers. Separate the lower neutral acid water layer A and the upper regenerated extract phase. The upper regenerated extract phase is used as the extract phase in extraction step-1 and is used for the extraction of the next batch of o-chlorophenylglycine wastewater B. The neutral acid water layer A is used to neutralize the neutral acid in step 4. Adjust the pH of the aqueous system to 6.5~7.0.
[0056] Example 3 In Example 2, after the 30th extraction cycle, the following data were recorded: A) loss of the first extractant in the extract phase; B) loss of the second extractant in the extract phase; C) loss of the third extractant in the extract phase; emulsification or flocculent formation in the extract phase; and the yield of the final product from step 4. Table 1 was obtained.
[0057] Table 1
[0058] △ indicates that the extract phase has emulsified; × indicates that the extract phase has not emulsified or has flocculent material; ≠ indicates that the extract phase has flocculent material.
[0059] Comparative Example 10 Traditional production process of o-chlorophenylglycine without extraction: Cyanidation step 1: Add 30.0 g ammonium bicarbonate, 40.0 g methanol, and 26.0 g of 30% sodium cyanide sequentially to a flask. Stir the system under closed conditions for 0.5 h. Then add 20.0 g of o-chlorobenzaldehyde. Heat to 65°C and maintain this temperature for 5 h. After the temperature is maintained, use a distillation apparatus to heat to 102°C to recover methanol and remove ammonia.
[0060] Hydrolysis step 2: After the recovery of methanol and the removal of ammonia are completed, add 40.0g of water and 80.80g of 32% sodium hydroxide aqueous solution, start heating to 140℃, and carry out hydrolysis reaction in a sealed environment for 4 hours.
[0061] Decolorization step 3: After hydrolysis, the system is heated to remove ammonia. After ammonia removal, the temperature is lowered to 80-85°C, 4g of activated carbon is added, and the system is kept at this temperature for 30 minutes for decolorization. After decolorization, the activated carbon is removed by centrifugation to obtain an aqueous phase system.
[0062] Neutralization step 4: After decolorization, adjust the pH of the system to 6.5~7.0 with dilute sulfuric acid, stir for 10 minutes, and then retest the pH to ensure it is within acceptable limits.
[0063] Crystallization step 5: After pH adjustment, cool to 25°C and stir for 1 hour to crystallize. After pH is retested and found to be qualified, filter, wash the filter cake with an appropriate amount of water, dry it, and dry the filter cake at 85°C to obtain the finished product o-chlorophenylglycine (yield 72.0%). Collect the wastewater containing o-chlorophenylglycine, which includes 1.5wt% o-chlorophenylglycine, 10wt% sodium sulfate, and 3wt% ammonium sulfate.
[0064] In comparison with Comparative Example 9 and Examples 2 and 3: Compared to the conventional production process of o-chlorophenylglycine in Comparative Example 10, Example 2 of this invention extracts the o-chlorophenylglycine-containing wastewater obtained in crystallization step 5 to obtain a neutralized acidic water layer A rich in o-chlorophenylglycine. Neutralized acidic water layer A is used to adjust the pH of the aqueous system in step 4, introducing o-chlorophenylglycine from the wastewater into the aqueous system, and recovering the o-chlorophenylglycine crystals from the wastewater. The yield of o-chlorophenylglycine is significantly increased from 72.0% to 87.2%. Example 3 compares different combinations of extractants and finds that bis(2-ethylhexyl) phosphate, (benzyl) phosphate, and other extractants are most effective. The extract phase OP-1 was prepared by mixing phenyl phosphonate and 4-methyl-3-penten-2-one oxime as a ternary extraction mixture and sulfonated kerosene / cyclohexane in a volume ratio of 2:1 as a diluent. This extract phase OP-1 did not produce emulsification or flocculent phenomena in multiple extraction cycles. The extraction rate of extract phase OP-1 reached 87.9% in the first extraction. After 30 extraction cycles, the components of the first, second, and third extractants in the ternary extraction mixture were less lost compared to OP-2 to OP-10. The yield of o-chlorophenylglycine was also much higher than that of other extractant combinations.
[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A process for producing o-chlorophenylglycine, comprising: Step 1: After mixing the alkali, alcohol, and sodium cyanide, o-chlorobenzaldehyde is added and the temperature is controlled to obtain the first mixture; Step 2: Mix the first mixture, water, and alkali, and control the temperature to obtain the second mixture; Step 3: The second mixture is added to activated carbon for adsorption and separation to obtain an aqueous phase system; Step 4: Adjust the pH of the aqueous system; Step 5: Temperature-controlled crystallization to obtain the finished product o-chlorophenylglycine and o-chlorophenylglycine wastewater B; Step 6: Use the extractant phase to extract o-chlorophenylglycine wastewater B to obtain the upper loaded extractant phase and the lower raffinate. Step 7: Add acid to the upper loaded extract phase to obtain neutralized acid water layer A and regenerated extract phase.
2. The o-chlorophenylglycine production process according to claim 1, characterized in that, The neutralized acidic water layer A obtained in step 7 is used to adjust the pH of the aqueous system in step 4.
3. The o-chlorophenylglycine production process according to claim 1 or 2, characterized in that, The regenerated extract phase obtained in step 7 is used as the extract phase in step 6 to extract o-chlorophenylglycine wastewater B in step 6, so as to obtain an upper loaded extract phase and a lower raffinate.
4. The o-chlorophenylglycine production process according to any one of claims 1 to 3, characterized in that, In step 1, the alcohol is selected from methanol, ethanol, isopropanol, or a mixture thereof; and / or, the alkali in step 1 is selected from sodium hydroxide, sodium tert-butoxide, potassium tert-butoxide, ammonium bicarbonate, or a combination thereof; and / or, the mass of alkali added per 1 kg of alcohol in step 1 is 500-800 g; and / or, the mass of sodium cyanide added per 1 kg of alcohol in step 1 is 400-750 g; and / or, the mass of o-chlorobenzaldehyde added per 1 kg of alcohol in step 1 is 400-600 g; and / or, the temperature in step 1 is controlled to 50-70°C.
5. The o-chlorophenylglycine production process according to any one of claims 1 to 4, characterized in that, In step 2, the mass of liquid alkali added to each 1L of water is 1.0~2.0kg; and / or, the temperature control method is to control the temperature to 120~160℃.
6. The o-chlorophenylglycine production process according to any one of claims 1 to 5, characterized in that, In step 4, the pH of the aqueous system is adjusted to 6.5-7.
0.
7. The o-chlorophenylglycine production process according to any one of claims 1 to 6, characterized in that, In step 5, the temperature-controlled crystallization method is to control the temperature to 20~30℃ for crystallization.
8. The o-chlorophenylglycine production process according to any one of claims 1 to 7, characterized in that, In step 6, the mixing volume ratio of the extract phase and the o-chlorophenylglycine wastewater B is 1:(8~12); and / or, the extraction temperature in step 6 is 2~35℃; and / or, the mass fraction of o-chlorophenylglycine in the o-chlorophenylglycine wastewater B is 1~2wt%; and / or, in step 7, the acid is selected from one or more of sulfuric acid, hydrochloric acid, and nitric acid; and / or, the mass fraction of the acid is 15~25%; and / or, in step 4, the pH of the aqueous phase system in step 4 is adjusted to 6.5~7.0 using neutralizing acid water layer A.
9. The o-chlorophenylglycine production process according to claim 8, characterized in that, The diluent includes one or more of sulfonated kerosene, cyclohexane, and n-octanol; and / or, the ternary extraction mixture includes a first extractant, a second extractant, and a third extractant, wherein each of the first, second, and third extractants is independently selected from one or more of bis(2-ethylhexyl) phosphate, (benzyl)phosphonate monophenyl ester, 4-methyl-3-penten-2-one oxime, dioctyl phthalate, 5-dodecyl-2-hydroxybenzaldehyde oxime, and tributyl phosphate.
10. The o-chlorophenylglycine production process according to claim 9, characterized in that, The volume ratio of sulfonated kerosene to cyclohexane in the diluent is (1~4):1; and / or, the molar ratio of the first extractant to the second extractant in the ternary extraction mixture is (8~12):(1~3); and / or, the molar ratio of the second extractant to the third extractant in the ternary extraction mixture is (1~3):(5~9).