CN117736068A - Green treatment method of methyl ether mother liquor in AE-active ester production - Google Patents
Green treatment method of methyl ether mother liquor in AE-active ester production Download PDFInfo
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- CN117736068A CN117736068A CN202311673431.XA CN202311673431A CN117736068A CN 117736068 A CN117736068 A CN 117736068A CN 202311673431 A CN202311673431 A CN 202311673431A CN 117736068 A CN117736068 A CN 117736068A
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- mother liquor
- methyl ether
- reaction
- ether mother
- active ester
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- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 239000012452 mother liquor Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 23
- 150000002148 esters Chemical class 0.000 title claims abstract description 19
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 75
- 238000006243 chemical reaction Methods 0.000 claims abstract description 33
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims abstract description 28
- 229910052938 sodium sulfate Inorganic materials 0.000 claims abstract description 28
- 235000011152 sodium sulphate Nutrition 0.000 claims abstract description 28
- DZXBHDRHRFLQCJ-UHFFFAOYSA-M sodium;methyl sulfate Chemical compound [Na+].COS([O-])(=O)=O DZXBHDRHRFLQCJ-UHFFFAOYSA-M 0.000 claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 14
- 239000000243 solution Substances 0.000 claims abstract description 14
- 239000003513 alkali Substances 0.000 claims abstract description 13
- 239000007788 liquid Substances 0.000 claims abstract description 13
- 238000003756 stirring Methods 0.000 claims abstract description 11
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000007787 solid Substances 0.000 claims abstract description 10
- 238000006460 hydrolysis reaction Methods 0.000 claims abstract description 9
- 238000010992 reflux Methods 0.000 claims abstract description 9
- 239000007864 aqueous solution Substances 0.000 claims abstract description 7
- 238000004821 distillation Methods 0.000 claims abstract description 7
- 230000007062 hydrolysis Effects 0.000 claims abstract description 6
- 238000001914 filtration Methods 0.000 claims abstract description 3
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 claims description 19
- 235000010288 sodium nitrite Nutrition 0.000 claims description 9
- 239000012153 distilled water Substances 0.000 claims description 4
- 239000010865 sewage Substances 0.000 claims description 4
- 238000001704 evaporation Methods 0.000 claims description 3
- 230000008020 evaporation Effects 0.000 claims description 3
- 238000004064 recycling Methods 0.000 claims description 2
- 239000006227 byproduct Substances 0.000 abstract description 13
- 238000011084 recovery Methods 0.000 abstract description 6
- 230000020477 pH reduction Effects 0.000 abstract description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 12
- 238000007069 methylation reaction Methods 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000006146 oximation reaction Methods 0.000 description 7
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- -1 benzothiazole 2-methoxyimino-2- (2-amino-4-thiazolyl) - (Z) thioacetate Chemical compound 0.000 description 5
- XYIBRDXRRQCHLP-UHFFFAOYSA-N ethyl acetoacetate Chemical compound CCOC(=O)CC(C)=O XYIBRDXRRQCHLP-UHFFFAOYSA-N 0.000 description 5
- 229920001131 Pulp (paper) Polymers 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 235000019353 potassium silicate Nutrition 0.000 description 4
- 239000003507 refrigerant Substances 0.000 description 4
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 4
- VAYGXNSJCAHWJZ-UHFFFAOYSA-N dimethyl sulfate Chemical compound COS(=O)(=O)OC VAYGXNSJCAHWJZ-UHFFFAOYSA-N 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 235000011121 sodium hydroxide Nutrition 0.000 description 3
- 210000003298 dental enamel Anatomy 0.000 description 2
- HASOOENYFDJEAK-UHFFFAOYSA-N ethyl 2-methoxyimino-3-oxobutanoate Chemical compound CCOC(=O)C(C(C)=O)=NOC HASOOENYFDJEAK-UHFFFAOYSA-N 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000005658 halogenation reaction Methods 0.000 description 2
- 230000011987 methylation Effects 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 229910052573 porcelain Inorganic materials 0.000 description 2
- 229930186147 Cephalosporin Natural products 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229940124587 cephalosporin Drugs 0.000 description 1
- 150000001780 cephalosporins Chemical class 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000005660 chlorination reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000026030 halogenation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000010413 mother solution Substances 0.000 description 1
- 150000002923 oximes Chemical class 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000007363 ring formation reaction Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a green treatment method of methyl ether mother liquor in AE-active ester production, which comprises the following steps: (1) acidification: adding concentrated sulfuric acid into the methyl ether mother liquor dropwise, and stirring for reacting for 20-40 min to obtain a reaction solution A; (2) hydrolysis: adding liquid alkali into the reaction liquid A, and carrying out reflux reaction to obtain reaction liquid B after the reaction is finished; (3) distillation recovery of methanol: distilling the reaction liquid B to distill out dilute methanol generated by the hydrolysis reaction; (4) concentrating and recovering sodium sulfate: the aqueous solution C after methanol distillation was concentrated to precipitate a white solid, and sodium sulfate was obtained after filtration. The invention carries out innocent treatment on methyl ether mother liquor, reduces the pollution of the monomethyl sulfate sodium to water, recovers sodium sulfate as a byproduct, and the obtained sodium sulfate has high purity and good color.
Description
Technical Field
The invention relates to the field of recovery treatment, in particular to a green treatment method of methyl ether mother liquor in AE-active ester production.
Background
AE-active ester, benzothiazole 2-methoxyimino-2- (2-amino-4-thiazolyl) - (Z) thioacetate of formula: c (C) 13 H 10 N 4 O 2 S 3 Molecular weight: 350.45 is an important medical intermediate, and is mainly used for synthesizing cephalosporin medicines; the structural formula is as follows:
ethyl acetoacetate is generally adopted as a raw material at present, and AE-active ester is prepared through the steps of oximation, methylation, halogenation, cyclization, hydrolysis, condensation and the like. Wherein, the ethyl acetoacetate and sodium nitrite aqueous solution undergo oximation reaction with dilute sulfuric acid to generate 2-hydroxamate ethyl acetoacetate (oxime compound for short), and the oxime compound is directly subjected to methylation reaction without separation. Sequentially adding caustic soda and dimethyl sulfate into the oximation reaction liquid to carry out methylation reaction to generate 2-methoxyiminoacetoacetic acid ethyl ester (methyl compound for short). After methylation reaction, toluene is generally added for extraction and delamination, and after toluene is recovered by concentration of an organic phase, the methylation compound is subjected to the next reaction; the water phase is methyl ether mother liquor.
According to analysis of the reaction process, a large amount of byproducts such as sodium sulfate and sodium methyl sulfate, and a small amount of sodium nitrite and other impurities exist in the methyl ether mother liquor. In patent CN103012312a, after the methylation reaction is finished, the solvent is recovered from the waste water and then directly discharged, but the sodium monomethyl sulfate has a significant influence on the water body, and the economic value of the byproduct sodium sulfate cannot be utilized. Patent CN109721513a reports a process for recovering sodium methyl sulfate as a byproduct in the production process of aminothiazoly loximate, and according to the description of the process, the obtained sodium methyl sulfate solid inevitably contains more sodium sulfate, but the two are difficult to separate and have lower purity.
Disclosure of Invention
The invention aims to overcome the technical defects, and provides a green treatment method for methyl ether mother liquor in AE-active ester production, which solves the technical problem of lower purity of recovered byproducts in methyl ether mother liquor in the prior art.
In order to achieve the technical purpose, the technical scheme provided by the invention is as follows:
in a first aspect, the invention provides a green treatment method of methyl ether mother liquor in AE-active ester production, which comprises the following steps: the method comprises the following steps: (1) acidification: adding concentrated sulfuric acid into the methyl ether mother liquor dropwise, and stirring for reacting for 20-40 min to obtain a reaction solution A; wherein the methyl ether mother liquor mainly contains sodium methyl sulfate, sodium sulfate and sodium nitrite; (2) hydrolysis: adding liquid alkali into the reaction liquid A, carrying out reflux reaction to hydrolyze sodium methyl sulfate in methyl ether mother liquor, and obtaining reaction liquid B after the reaction is finished; (3) distillation recovery of methanol: distilling the reaction liquid B to distill out dilute methanol generated by the hydrolysis reaction; (4) concentrating and recovering sodium sulfate: the aqueous solution C after methanol distillation was concentrated to precipitate a white solid, and sodium sulfate was obtained after filtration.
Compared with the prior art, the invention has the beneficial effects that:
the invention carries out innocent treatment on the methyl ether mother liquor, reduces the pollution of the sodium monomethyl sulfate to the water body, and recovers sodium sulfate as a byproduct. The sodium sulfate obtained by the method has high purity and good color, can be used for preparing water glass, porcelain glaze, paper pulp, refrigerant mixture and the like, and realizes certain economic value.
Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The invention aims at the treatment of the aqueous-phase methyl ether mother liquor generated in the AE-active ester preparation process; the specific sources are as follows:
(1) Oximation reaction
Adding a certain amount of solution prepared from sodium nitrite and water into an oximation reaction kettle, then adding the ethyl acetoacetate with the feeding amount, and uniformly stirring. Adding sulfuric acid and water in certain proportion into the system at-5-30 deg.c and maintaining the temperature at-5-30 deg.c to react. After the reaction, 2-hydroxamic acetoacetic acid ethyl ester (abbreviated as oxime) which is an oximation reaction product enters a methylation reaction procedure; the chemical reaction formula is as follows:
(2) Methylation reaction
Maintaining the temperature at-5-30 ℃, adding liquid alkali and dimethyl sulfate into a reaction kettle after the oximation reaction is completed, and performing methylation reaction to generate 2-methoxyiminoacetoacetic acid ethyl ester (methyl compound for short); the chemical reaction formula is as follows:
after the methylation reaction is finished, adding a certain amount of toluene, carrying out extraction layering, concentrating an organic phase, recovering toluene, transferring into a chlorination reaction kettle, and carrying out a next halogenation reaction to prepare a final product of aminothioxime acid; the water phase is the methyl ether mother liquor to be treated in the invention.
The methyl ether mother liquor mainly contains sodium methyl sulfate, sodium nitrite and the like.
The main processing steps of the invention include the following steps:
(1) Acidifying: adding concentrated sulfuric acid into the methyl ether mother liquor dropwise, and stirring for reacting for 20-40 min to obtain a reaction solution A;
(2) Hydrolysis: adding liquid alkali into the reaction liquid A, carrying out reflux reaction to hydrolyze sodium methyl sulfate therein, and obtaining reaction liquid B after the reaction is finished; the chemical reaction formula is as follows:
NaMeSO 4 +NaOH→MeOH+Na 2 SO 4
(3) And (3) distilling and recovering methanol: distilling the reaction liquid B to evaporate dilute methanol, and comprehensively utilizing the distilled dilute methanol as a byproduct;
(4) Concentrating and recovering sodium sulfate: concentrating the water solution C after methanol is distilled out, and enabling distilled water to enter a sewage treatment system; the white solid precipitated is filtered to obtain sodium sulfate as a byproduct for producing water glass, enamel, paper pulp, refrigerant mixture and the like. Among them, the sewage treatment system is more common, and the distilled water can be treated without specific limitation.
Preferably, in the step (1), the volume ratio of the methyl ether mother liquor to the concentrated sulfuric acid is (50-100): 1; more preferably (60 to 90): 1, still more preferably (70 to 80): 1.
Preferably, in the step (1), the temperature of the stirring reaction is 95-100 ℃.
Preferably, in the step (1), the stirring reaction time is 20 to 40 minutes.
Preferably, in the step (2), the reaction solution A is cooled to 80 ℃ or lower, and a liquid alkali is added.
Preferably, in the step (2), the volume ratio of the added liquid alkali to the methyl ether mother liquor is 1 (4-6).
Preferably, in the step (2), the reflux reaction is carried out at 80 to 102℃for 2 to 3 hours.
Preferably, in the step (3), the concentration of distilled dilute methanol is 25-30%, and the volume of distilled dilute methanol is 20-40% of that of methyl ether mother liquor; and (3) collecting the diluted methanol as a byproduct according to the volume, and recycling and comprehensively utilizing the diluted methanol.
Preferably, in the step (4), the aqueous solution C enters a double-effect evaporation system for concentration.
The invention has the main action mechanism and advantages that:
according to the invention, by acidifying the methyl ether mother liquor, most of excessive unreacted sodium nitrite can be removed, and high residue in finally obtained sodium sulfate is avoided; and adding sodium hydroxide into the methyl ether mother solution, hydrolyzing dimethyl sulfate and sodium methyl sulfate, concentrating until solid is separated out, separating the solid and drying to obtain sodium sulfate as a byproduct. The invention carries out innocent treatment on the methyl ether mother liquor, reduces the pollution of the sodium monomethyl sulfate to the water body, and recovers sodium sulfate as a byproduct. The sodium sulfate obtained by the method has high purity and good color, and can be used for preparing water glass, porcelain glaze, paper pulp, refrigerant mixture and the like, thereby realizing certain economic value.
The invention is further illustrated by the following specific examples.
The methyl ether mother liquor parameters for each of the following examples and comparative examples were: each batch of 3000 liters of methyl ether mother liquor contains 804 kg of sodium methyl sulfate, 436 kg of sodium sulfate and 91 kg of sodium nitrite; the equipment used in the invention, such as a recovery kettle and the like, is conventional equipment.
Example 1
1. Acidifying: and (3) opening a water layer feeding valve of the recovery kettle, adding 3000 liters of methyl ether mother liquor, stirring, dripping 40 liters of concentrated sulfuric acid, opening a reflux device, starting steam to heat, keeping the temperature in the kettle at 100 ℃, and stirring for reaction for 30min to obtain a reaction liquid A. In the process, brown red nitrogen oxide gas overflows and is discharged to an induced draft tube for absorption.
2. Hydrolysis: the reaction solution A was cooled to 80℃or lower, and 600 liters of liquid alkali was quantitatively added by opening a liquid alkali feed valve. Starting steam, heating to 100-102 ℃ and carrying out reflux reaction for 2-3 hours to obtain a reaction solution B.
3. And (3) distilling and recovering methanol: the reflux unit was turned off, and the distillation unit was turned on to distill the reaction solution B to distill 1000 liters of diluted methanol having a concentration of about 28% and to comprehensively utilize the distilled diluted methanol as a by-product.
4. Concentrating and recovering sodium sulfate: the water solution C after methanol is distilled out enters a double-effect evaporation system for concentration, and distilled water enters a sewage treatment system. The white solid precipitated is filtered to obtain sodium sulfate as a byproduct for producing water glass, enamel, paper pulp, refrigerant mixture and the like.
The average methyl ether mother liquor of each batch can obtain 1300 kg of white sodium sulfate solid sodium sulfate with the purity of more than 99 percent.
Comparative example 1
The only difference from example 1 is that: the acidification step of step 1 is removed, and liquid alkali is directly added into the methyl ether mother liquor, and other steps and conditions are the same as in example 1.
As a result, it was found that a small amount of sodium nitrite was present in the sodium sulfate solid, and the purity was lowered. And brown red nitrogen oxide toxic gas can be generated in the subsequent use.
Comparative example 2
The only difference from example 1 is that: removing the cooling step in the step 2, and directly adding liquid alkali; other steps and conditions were the same as in example 1.
As a result, the reaction was found to be too intense, affecting the production safety.
Comparative example 3
The only difference from example 1 is that: removing the distillation step in the step 3, and directly introducing the reaction solution B into the step 4 for concentration and sodium sulfate recovery; other steps and conditions were the same as in example 1.
As a result, it was found that 25 to 30% of the diluted methanol could not be recovered and reused, increasing the cost.
The above-described embodiments of the present invention do not limit the scope of the present invention. Any other corresponding changes and modifications made in accordance with the technical idea of the present invention shall be included in the scope of the claims of the present invention.
Claims (10)
1. The green treatment method of the methyl ether mother liquor in AE-active ester production is characterized by comprising the following steps:
(1) Acidifying: adding concentrated sulfuric acid into the methyl ether mother liquor dropwise, and stirring for reacting for 20-40 min to obtain a reaction solution A; wherein the methyl ether mother liquor mainly contains sodium methyl sulfate, sodium sulfate and sodium nitrite;
(2) Hydrolysis: adding liquid alkali into the reaction liquid A, carrying out reflux reaction to hydrolyze sodium methyl sulfate in methyl ether mother liquor, and obtaining reaction liquid B after the reaction is finished;
(3) And (3) distilling and recovering methanol: distilling the reaction liquid B to distill out dilute methanol generated by the hydrolysis reaction;
(4) Concentrating and recovering sodium sulfate: the aqueous solution C after methanol distillation was concentrated to precipitate a white solid, and sodium sulfate was obtained after filtration.
2. The method for green treatment of methyl ether mother liquor in AE-active ester production according to claim 1 wherein in step (1), the volume ratio of methyl ether mother liquor to concentrated sulfuric acid is (50-100): 1.
3. The method for green treatment of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (1), the temperature of stirring reaction is 95-100 ℃.
4. The green treatment method of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (1), stirring reaction is preferably carried out for 20-40 min.
5. The method for green treatment of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (2), the reaction solution a is cooled to 80 ℃ or lower and a liquid alkali is added.
6. The green treatment method of methyl ether mother liquor in AE-active ester production according to claim 1 wherein in step (2), the volume ratio of added liquid alkali to methyl ether mother liquor is 1 (4-6).
7. The method for green treatment of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (2), the reflux reaction is carried out at 80-102 ℃ for 2-3 hours.
8. The green treatment method of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (3), the concentration of distilled dilute methanol is 25-30%, and the distilled volume is 20-40% of the methyl ether mother liquor; and recycling the diluted methanol.
9. The green treatment method of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (4), the aqueous solution C enters a double effect evaporation system for concentration.
10. The method for green treatment of methyl ether mother liquor in AE-active ester production according to claim 1, wherein in step (4), the distilled water enters a sewage treatment system after the aqueous solution C is concentrated.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311673431.XA CN117736068A (en) | 2023-12-07 | 2023-12-07 | Green treatment method of methyl ether mother liquor in AE-active ester production |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311673431.XA CN117736068A (en) | 2023-12-07 | 2023-12-07 | Green treatment method of methyl ether mother liquor in AE-active ester production |
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| Publication Number | Publication Date |
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| CN202311673431.XA Pending CN117736068A (en) | 2023-12-07 | 2023-12-07 | Green treatment method of methyl ether mother liquor in AE-active ester production |
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- 2023-12-07 CN CN202311673431.XA patent/CN117736068A/en active Pending
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