CN113861011A - Production process of o-methylphenylacetic acid - Google Patents
Production process of o-methylphenylacetic acid Download PDFInfo
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- CN113861011A CN113861011A CN202111206704.0A CN202111206704A CN113861011A CN 113861011 A CN113861011 A CN 113861011A CN 202111206704 A CN202111206704 A CN 202111206704A CN 113861011 A CN113861011 A CN 113861011A
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- RZWGTXHSYZGXKF-UHFFFAOYSA-N 2-(2-methylphenyl)acetic acid Chemical compound CC1=CC=CC=C1CC(O)=O RZWGTXHSYZGXKF-UHFFFAOYSA-N 0.000 title claims abstract description 32
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims abstract description 83
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 51
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 45
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 44
- 238000006243 chemical reaction Methods 0.000 claims abstract description 29
- 238000010992 reflux Methods 0.000 claims abstract description 21
- 238000001816 cooling Methods 0.000 claims abstract description 18
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 235000011121 sodium hydroxide Nutrition 0.000 claims abstract description 15
- 239000007788 liquid Substances 0.000 claims abstract description 13
- -1 o-methyl cyanobenzyl Chemical group 0.000 claims abstract description 12
- 238000001914 filtration Methods 0.000 claims abstract description 10
- 239000002351 wastewater Substances 0.000 claims abstract description 8
- 239000000498 cooling water Substances 0.000 claims abstract description 5
- 238000003756 stirring Methods 0.000 claims description 30
- 239000012071 phase Substances 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 8
- 239000012074 organic phase Substances 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 7
- 230000008569 process Effects 0.000 claims description 5
- 239000002699 waste material Substances 0.000 claims description 5
- 238000002425 crystallisation Methods 0.000 claims description 4
- 230000008025 crystallization Effects 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 238000005406 washing Methods 0.000 claims description 4
- 230000018044 dehydration Effects 0.000 claims description 3
- 238000006297 dehydration reaction Methods 0.000 claims description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000004134 energy conservation Methods 0.000 abstract description 3
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000011112 process operation Methods 0.000 abstract description 3
- 239000000126 substance Substances 0.000 abstract description 3
- 239000000047 product Substances 0.000 description 12
- 230000009471 action Effects 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 239000012043 crude product Substances 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- ZPSJGADGUYYRKE-UHFFFAOYSA-N 2H-pyran-2-one Chemical compound O=C1C=CC=CO1 ZPSJGADGUYYRKE-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000005903 acid hydrolysis reaction Methods 0.000 description 1
- 238000005904 alkaline hydrolysis reaction Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229940127554 medical product Drugs 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 239000000575 pesticide Substances 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
- 238000001953 recrystallisation Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/08—Preparation of carboxylic acids or their salts, halides or anhydrides from nitriles
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the technical field of organic chemical product production and discloses a production process of o-methylphenylacetic acid, which comprises the following steps of adding water into a reaction kettle, adding sulfuric acid, and starting cooling water of a condenser; after the sulfuric acid is added, slowly dropwise adding o-methyl cyanobenzyl under the reflux condition; after the reflux reaction is finished, cooling the reaction kettle, then feeding the reaction kettle into a 2000L treatment kettle, and adding toluene and water; adding water into a 2000L treatment kettle, dropwise adding liquid caustic soda, standing and layering; adding toluene into a treatment kettle, extracting the water phase once, then acidifying the water phase with sulfuric acid, adding toluene, heating, standing and layering; heating, refluxing, dehydrating, cooling, crystallizing, cooling, centrifuging, and filtering to obtain o-tolylacetic acid. The production process of o-methylphenylacetic acid has simple and convenient process operation and few steps, reduces the loss of products, ensures that the product yield reaches more than 95 percent, reduces the production cost, can also reduce a large amount of waste water, and is beneficial to environmental protection and energy conservation.
Description
Technical Field
The invention relates to the technical field of organic chemical product production, in particular to a production process of o-methylphenylacetic acid.
Background
O-methylphenylacetic acid is an important organic chemical intermediate, is mainly used for manufacturing pesticides and medical products, and can be particularly used as a raw material for synthesizing pyrone.
The methods for preparing o-tolylacetic acid have less published reports, and the data related to the synthesis method are in the same category. (1) The method for preparing organic acid in books such as the book of practical organic chemistry handbook (pages 347 to 348) and the book of Jianjing organic chemistry (pages 224 to 225) of Li art text is to carry out hydrolysis reaction on corresponding organic nitrile compounds in strong acid with high concentration (such as concentrated hydrochloric acid and 20 to 75 percent of sulfuric acid) or sodium hydroxide solution with 10 to 50 percent, and the generated crude product needs to be refined by recrystallization. The total yield of acid hydrolysis is 75-85%, and the total yield of alkaline hydrolysis is 52-75%; (2) the synthesis method of o-methylphenylacetic acid reported in Chinese patent CN1927801A is hydrolysis by acid, and the adopted refining method is as follows: and dissolving the prepared crude product with a sodium hydroxide solution, decoloring and filtering the solution by using active carbon, adding an acid solution to adjust the pH value to 1-4, and separating out an o-tolylacetic acid product with the total yield of 90.05%.
The existing method for preparing o-tolylacetic acid has various inconveniences, such as long reaction time, low product yield, complex operation steps, and the production of wastewater and waste residues in the preparation process, which is not beneficial to environmental protection.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a production process of o-tolylacetic acid, which can effectively improve the quality and the yield of the o-tolylacetic acid.
In order to realize the purpose of the production process of o-tolylacetic acid, the invention provides the following technical scheme: a production process of o-tolylacetic acid comprises the following steps:
firstly, adding water into a 1000L reaction kettle, starting a stirring device for stirring, slowly adding sulfuric acid through an elevated tank, and starting cooling water of a condenser;
secondly, after the sulfuric acid is added, heating the reaction kettle to 120-125 ℃, slowly dripping the o-methyl cyanobenzyl under the reflux condition, and carrying out reflux reaction for 3 hours;
thirdly, cooling the reaction kettle to 90-100 ℃ after the reflux reaction is finished, then feeding the reaction materials into a 2000L treatment kettle, adding toluene and water, keeping the temperature at about 90 ℃, standing for layering after stirring, and removing the water of the lower waste acid;
fourthly, adding water into a 2000L treatment kettle, dropwise adding liquid caustic soda under stirring, adjusting the pH value to be more than or equal to 10, stopping stirring, standing for layering, separating a lower-layer water phase into another 2000L treatment kettle, and barreling an organic phase for treatment;
fifthly, adding toluene into the treatment kettle to extract the water phase once, then acidifying the water phase with sulfuric acid to ensure that the pH value is less than or equal to 2, adding toluene, heating, standing for layering, discarding the lower layer wastewater, washing once again, namely purifying water, and feeding the organic phase into a crystallization kettle;
and sixthly, heating up, refluxing and dehydrating, cooling and crystallizing after dehydration is completed, separating out solids at 40 ℃, continuously cooling, stirring, centrifugally filtering to obtain the product o-methylphenylacetic acid, and drying.
Preferably, the total feeding ratio of the o-methyl cyanobenzyl, the sulfuric acid, the water and the liquid caustic soda in the production process is 1:3:13: 2.3.
Preferably, in the second step, o-methyl cyanobenzyl is slowly dripped under the reflux condition, the o-methyl cyanobenzyl needs to be added within 1 hour, and the temperature is controlled between 120 ℃ and 130 ℃.
Preferably, the amounts of the added toluene and water in the third step are 160-170 kg of toluene and 190-200 kg of water respectively.
Preferably, in the fourth step, water is added into the 2000L treatment kettle, the mass of the water is 1000-1100 kg, and liquid caustic soda is dropwise added under stirring, the concentration of the liquid caustic soda is 30%, and the mass of the liquid caustic soda is 300-310 kg.
Preferably, in the fifth step, toluene is added into the treatment kettle to extract the water phase once, then sulfuric acid is used to acidify the water phase, the mass of the toluene is 160-170 kg, the concentration of the sulfuric acid is 50%, the mass of the toluene is 230kg, the temperature is increased, the mass of the toluene is 290-300 kg, and the temperature is increased to about 90 ℃.
Preferably, the cooling is continued in the sixth step, then the stirring is carried out, the cooling temperature is below 10 ℃, the stirring time is 1-1.5 hours, the o-tolylacetic acid product is obtained by centrifugal filtration, and then the drying is carried out, wherein the drying temperature is 45-55 ℃.
Compared with the prior art, the invention provides a production process of o-methylphenylacetic acid, which has the following beneficial effects:
the production process of o-methylphenylacetic acid has the advantages of simple and convenient process operation, few steps, reduction of product loss, product yield of more than 95 percent, centralized collection and treatment of residues after centrifugal filtration due to no need of purification and refining, partial products can be obtained, production cost is reduced, a large amount of waste water can be reduced, and environmental protection and energy conservation are facilitated.
Drawings
FIG. 1 is a reaction equation diagram of the o-tolylacetic acid production process of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in 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.
Referring to fig. 1, the following embodiment is given:
a production process of o-tolylacetic acid comprises the following steps:
s1, adding water into a 1000L reaction kettle, starting a stirring device to stir, slowly adding sulfuric acid through an overhead tank, and starting cooling water of a condenser;
s2, after the sulfuric acid is added, heating the reaction kettle to 120-125 ℃, slowly dripping the o-methyl cyanobenzyl under the reflux condition, finishing the addition within 1 hour, controlling the temperature at 120 ℃, and carrying out reflux reaction for 3 hours;
s3, cooling the reaction kettle to 90-100 ℃ after the reflux reaction is finished, then feeding the reaction materials into a 2000L treatment kettle, adding 160kg of toluene and 190kg of water, keeping the temperature at about 90 ℃, standing for layering after stirring, and discarding the water of the lower waste acid;
s4, adding 1000kg of water into a 2000L treatment kettle, dropwise adding 300kg of 30% liquid caustic soda under stirring, adjusting the pH value to be more than or equal to 10, stopping stirring, standing for layering, separating a lower-layer water phase into another 2000L treatment kettle, and barreling an organic phase for treatment;
s5, adding 160kg of toluene into a treatment kettle to extract the water phase once, then acidifying the water phase by 230kg of 50% sulfuric acid to ensure that the pH value is less than or equal to 2, adding 290kg of toluene, heating to about 90 ℃, standing for layering, discarding the lower layer wastewater, washing once again, namely purifying the water, and feeding the organic phase into a crystallization kettle;
s6, heating, refluxing, dehydrating, cooling, crystallizing after dehydration is completed, beginning to precipitate solids at 40 ℃, continuing to cool to below 10 ℃, stirring for 1 hour, centrifugally filtering to obtain the product o-tolylacetic acid, and drying at 45 ℃.
The following example II is given:
a production process of o-tolylacetic acid comprises the following steps:
s1, adding water into a 1000L reaction kettle, starting a stirring device to stir, slowly adding sulfuric acid through an overhead tank, and starting cooling water of a condenser;
s2, after the sulfuric acid is added, heating the reaction kettle to 120-125 ℃, slowly dripping the o-methyl cyanobenzyl under the reflux condition, finishing the addition within 1 hour, controlling the temperature at 130 ℃, and carrying out reflux reaction for 3 hours;
s3, cooling the reaction kettle to 90-100 ℃ after the reflux reaction is finished, then feeding the reaction materials into a 2000L treatment kettle, adding 170kg of methylbenzene and 200kg of water, keeping the temperature at about 90 ℃, standing for layering after stirring, and discarding the water of the lower waste acid;
s4, adding 1100kg of water into a 2000L treatment kettle, dropwise adding 310kg of 30% liquid caustic soda under stirring, adjusting the pH value to be more than or equal to 10, stopping stirring, standing for layering, separating a lower-layer water phase into another 2000L treatment kettle, and barreling an organic phase for treatment;
s5, adding 170kg of toluene into a treatment kettle to extract the water phase once, then acidifying the water phase by 230kg of 50% sulfuric acid to ensure that the pH value is less than or equal to 2, adding 300kg of toluene, heating to about 90 ℃, standing for layering, discarding the lower layer wastewater, washing once again, namely purifying the water, and feeding the organic phase into a crystallization kettle;
s6, heating, refluxing, dehydrating, cooling, crystallizing, separating out solid at 40 ℃, cooling to below 10 ℃, stirring for 1.5 hours, centrifuging, filtering to obtain o-tolylacetic acid, and drying at 55 ℃.
The working use flow and the installation method of the invention are that when the o-tolylacetic acid production process is used, the process operation is simple and convenient, the steps are few, the product loss is reduced, the total amount of the product can be about 270kg, the content is 99%, the yield is 95%, the melting point is 88-90, and because purification and refining are not needed, the residue after centrifugal filtration is collected and treated in a centralized manner, a part of the product can be obtained, the production cost is reduced, a large amount of waste water can be reduced, and the environment protection and energy conservation are facilitated.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. The production process of o-tolylacetic acid is characterized by comprising the following steps:
firstly, adding water into a 1000L reaction kettle, starting a stirring device for stirring, slowly adding sulfuric acid through an elevated tank, and starting cooling water of a condenser;
secondly, after the sulfuric acid is added, heating the reaction kettle to 120-125 ℃, slowly dripping the o-methyl cyanobenzyl under the reflux condition, and carrying out reflux reaction for 3 hours;
thirdly, cooling the reaction kettle to 90-100 ℃ after the reflux reaction is finished, then feeding the reaction materials into a 2000L treatment kettle, adding toluene and water, keeping the temperature at about 90 ℃, standing for layering after stirring, and removing the water of the lower waste acid;
fourthly, adding water into a 2000L treatment kettle, dropwise adding liquid caustic soda under stirring, adjusting the pH value to be more than or equal to 10, stopping stirring, standing for layering, separating a lower-layer water phase into another 2000L treatment kettle, and barreling an organic phase for treatment;
fifthly, adding toluene into the treatment kettle to extract the water phase once, then acidifying the water phase with sulfuric acid to ensure that the pH value is less than or equal to 2, adding toluene, heating, standing for layering, discarding the lower layer wastewater, washing once again, namely purifying water, and feeding the organic phase into a crystallization kettle;
and sixthly, heating up, refluxing and dehydrating, cooling and crystallizing after dehydration is completed, separating out solids at 40 ℃, continuously cooling, stirring, centrifugally filtering to obtain the product o-methylphenylacetic acid, and drying.
2. The o-tolylacetic acid production process according to claim 1, wherein: in the production process, the total feed ratio of the o-methyl cyanobenzyl, the sulfuric acid, the water and the liquid caustic soda is 1:3:13: 2.3.
3. The second step of claim 1, wherein the o-tolylacetic acid production process comprises: under the reflux condition, o-methyl cyanobenzyl is slowly dripped, the o-methyl cyanobenzyl needs to be added within 1 hour, and the temperature is controlled between 120 ℃ and 130 ℃.
4. The process for producing o-tolylacetic acid according to the third step of claim 1, wherein: the amount of the added toluene and the amount of the added water are 160-170 kg of toluene and 190-200 kg of water respectively.
5. The fourth step of claim 1, wherein said o-tolylacetic acid production process comprises: adding water into the 2000L treatment kettle, wherein the mass of the water is 1000-1100 kg, and dropwise adding liquid caustic soda under stirring, the concentration of the liquid caustic soda is 30%, and the mass of the liquid caustic soda is 300-310 kg.
6. The process according to the fifth step of claim 1, wherein: adding toluene into a treatment kettle to extract the water phase once, then acidifying the water phase with sulfuric acid, wherein the mass of the toluene is 160-170 kg, the concentration of the sulfuric acid is 50%, the mass of the toluene is 230kg, adding toluene, heating, the mass of the toluene is 290-300 kg, and heating to about 90 ℃.
7. The process according to the sixth step of claim 1, wherein: and continuously cooling, stirring, wherein the cooling temperature is below 10 ℃, the stirring time is 1-1.5 hours, centrifuging and filtering to obtain the product o-tolylacetic acid, and drying, wherein the drying temperature is 45-55 ℃.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111206704.0A CN113861011A (en) | 2021-10-15 | 2021-10-15 | Production process of o-methylphenylacetic acid |
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| CN202111206704.0A CN113861011A (en) | 2021-10-15 | 2021-10-15 | Production process of o-methylphenylacetic acid |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1927801A (en) * | 2006-09-18 | 2007-03-14 | 武汉有机实业股份有限公司 | Preparation method of methylphenyl acetic acid |
| JP2010184904A (en) * | 2009-01-13 | 2010-08-26 | Sumitomo Chemical Co Ltd | Method for producing acetic acid compound |
| CN106278861A (en) * | 2016-08-24 | 2017-01-04 | 河北诚信有限责任公司 | A kind of method preparing substituted phenylacetic acid |
-
2021
- 2021-10-15 CN CN202111206704.0A patent/CN113861011A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1927801A (en) * | 2006-09-18 | 2007-03-14 | 武汉有机实业股份有限公司 | Preparation method of methylphenyl acetic acid |
| JP2010184904A (en) * | 2009-01-13 | 2010-08-26 | Sumitomo Chemical Co Ltd | Method for producing acetic acid compound |
| CN106278861A (en) * | 2016-08-24 | 2017-01-04 | 河北诚信有限责任公司 | A kind of method preparing substituted phenylacetic acid |
Non-Patent Citations (1)
| Title |
|---|
| 胡文州: "3-异色酮的合成工艺研究", 《中国优秀硕士学位论文全文数据库 工程科技I辑》, no. 05, pages 29 * |
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