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CN111018757B - Method for synthesizing 3-mercaptopropionic acid from acidic waste gas - Google Patents

Method for synthesizing 3-mercaptopropionic acid from acidic waste gas Download PDF

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CN111018757B
CN111018757B CN201911347062.9A CN201911347062A CN111018757B CN 111018757 B CN111018757 B CN 111018757B CN 201911347062 A CN201911347062 A CN 201911347062A CN 111018757 B CN111018757 B CN 111018757B
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hydrogen sulfide
acid
synthesizing
gas
waste gas
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CN111018757A (en
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黎广贞
张海涛
张容
杨国忠
李伟良
吴雅倩
高振东
刘清
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Guangdong Zhonggao Technology Co ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C319/00Preparation of thiols, sulfides, hydropolysulfides or polysulfides
    • C07C319/02Preparation of thiols, sulfides, hydropolysulfides or polysulfides of thiols
    • C07C319/04Preparation of thiols, sulfides, hydropolysulfides or polysulfides of thiols by addition of hydrogen sulfide or its salts to unsaturated compounds

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  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The invention relates to the technical field of synthesis of mercapto compounds, and particularly relates to a method for synthesizing 3-mercaptopropionic acid from acidic waste gas. The method comprises the first step of purifying hydrogen sulfide in the acid waste gas by a pressure swing adsorption method; secondly, synthesizing 3-mercaptopropionic acid: step one, selecting materials; step two, the first step reaction; step three, the second step reaction; step four, the third step reaction. The method for synthesizing 3-mercaptopropionic acid from acidic waste gas adopts a method of changing hydrogen sulfide in acidic waste gas discharged by an oil refinery into valuable, taking reasonable utilization of resources as guidance, and synthesizing 3-mercaptopropionic acid with low cost and less three wastes. The invention takes acrylic acid and hydrogen sulfide products obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent, so that the reaction conversion rate is high, the yield is high, byproducts are reduced, the traditional process route is broken through, and the problem of three wastes caused by acidification and extraction is avoided, therefore, the invention is an excellent synthesis and post-treatment route.

Description

Method for synthesizing 3-mercaptopropionic acid from acidic waste gas
Technical Field
The invention relates to the technical field of synthesis of mercapto compounds, and particularly relates to a method for synthesizing 3-mercaptopropionic acid from acidic waste gas.
Background
The 3-mercaptopropionic acid is an important chemical raw material, and the main application fields are medicines, auxiliaries, water reducing agents and the like. Can be used for preparing medicine Finalou (clomezazone), which has effects of improving sleep and tranquilization; can be used for preparing pentaerythritol tetra (3-mercaptopropionate), which is an intermediate for organic synthesis and can be used in the field of paint as a curing agent; can be used for preparing polycarboxylic acid high-efficiency water reducing agent and synthesizing heat stabilizers such as organic tin, organic antimony and the like. At present, acrylonitrile and sodium hydrosulfide are used as raw materials to produce the acrylonitrile and the sodium hydrosulfide at home and abroad, the process can be carried out under normal pressure, but the acrylonitrile is a highly toxic product and is regulated by public security departments, the process flow is long, the reaction temperature and the reaction time are strictly required, the operation flexibility is low, the three wastes are more, the environmental pollution is large, and the process tends to be gradually eliminated.
In the prior art, although a method for effectively synthesizing 3-mercaptopropionic acid by using hydrogen sulfide and acrylic acid is disclosed, the traditional process route is to directly use pure hydrogen sulfide for preparation, so that the production cost is higher, acidification is easy to generate, and the three wastes are caused during extraction.
In addition, a large amount of acid waste gas is discharged in the production process of the oil refinery, and the acid waste gas contains hydrogen sulfide, so that if the acid waste gas is utilized, the waste can be changed into valuable.
Disclosure of Invention
The invention aims to provide a method for synthesizing 3-mercaptopropionic acid from acidic waste gas, which can change waste into valuable and avoid the 'three wastes' problem caused by acidification and extraction.
In order to achieve the purpose, the invention adopts the following technical scheme:
the method for synthesizing the 3-mercaptopropionic acid by using the acidic waste gas comprises the following steps:
first, the pressure swing adsorption process purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then carrying out flash evaporation on the liquid phase, carrying out first separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesizing 3-mercaptopropionic acid
Step one, selecting materials: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent;
step two, the first step reaction: under the protection of inert gas and with controlled temperature, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for a certain time;
step three, reaction in the second step: heating to a certain temperature, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding the acrylic acid;
step four, reaction in the third step: then the rest hydrogen sulfide product is added, stirred and reacted for a certain time, and then the 3-mercaptopropionic acid is obtained through reduced pressure rectification.
In the above technical solution, in the first step of the second step, the molar ratio of the acrylic acid to the hydrogen sulfide in the hydrogen sulfide product is 1: 1 to 4.
In the above technical solution, in the first step of the second step, the molar ratio of the acrylic acid to the hydrogen sulfide in the hydrogen sulfide product is 1: 3.
in the above technical solution, in the step one of the second step, the molar ratio of the acrylic acid to the triethylamine to the dimethylacetamide is 1: 0.1-0.4: 2 to 5.
In the above technical scheme, in the step one of the second step, the molar ratio of the acrylic acid to the triethylamine to the dimethylacetamide is 1:0.2: 3.5.
In the technical scheme, in the second step, under the protection of inert gas and at the temperature of 5-15 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 2-3 hours.
In the technical scheme, in the third step of the second step, the temperature is raised to 75-85 ℃, then acrylic acid is dripped for reaction, and the time for dripping acrylic acid is controlled to be 1.5-2.5 h.
In the technical scheme, in the fourth step of the second step, the rest hydrogen sulfide product is introduced, stirred and reacted for 4-6 h, and then the 3-mercaptopropionic acid is obtained through reduced pressure rectification.
In the technical scheme, the molar ratio of hydrogen sulfide of part of hydrogen sulfide products in the second step to hydrogen sulfide of the rest hydrogen sulfide products in the fourth step is 2-3: 1.
Compared with the prior art, the invention has the beneficial effects that:
(1) the method for synthesizing 3-mercaptopropionic acid from acidic waste gas provided by the invention adopts hydrogen sulfide in acidic waste gas discharged from an oil refinery, changes waste into valuable, takes reasonable utilization of resources as guidance, and synthesizes 3-mercaptopropionic acid with low cost and less three wastes. The invention takes acrylic acid and hydrogen sulfide products obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent, so that the reaction conversion rate is high, the yield is high, byproducts are reduced, the traditional process route is broken through, and the problem of three wastes caused by acidification and extraction is avoided, therefore, the invention is an excellent synthesis and post-treatment route.
(2) The method for synthesizing the 3-mercaptopropionic acid by using the acidic waste gas has the characteristics of simple method, low production cost and suitability for industrial large-scale application.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps:
first, the pressure swing adsorption process purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then carrying out flash evaporation on the liquid phase, carrying out first separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesis of 3-mercaptopropionic acid
Step one, selecting materials: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent; in this example, the molar ratio of acrylic acid to hydrogen sulfide in the hydrogen sulfide product was 1: 3; in this example, the molar ratio of acrylic acid to triethylamine to dimethylacetamide is 1:0.2: 3.5;
step two, the first step reaction: under the protection of inert gas and at the temperature of 10 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 2.5 hours;
step three, reaction in the second step: heating to 80 ℃, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding acrylic acid to be 2 h;
step four, reaction in the third step: and then introducing the rest hydrogen sulfide product, stirring for reaction for 5 hours, and then carrying out reduced pressure rectification to obtain the 3-mercaptopropionic acid.
In this example, the molar ratio of hydrogen sulfide from a portion of the hydrogen sulfide product in step two of the second step to the remainder of the hydrogen sulfide product in step four was 2.5: 1.
Example 2.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps:
first, the pressure swing adsorption method purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then, carrying out flash evaporation on the liquid phase, carrying out primary separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesizing 3-mercaptopropionic acid
Step one, selecting materials: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent; in this example, the molar ratio of acrylic acid to hydrogen sulfide in the hydrogen sulfide product was 1: 1; in this example, the molar ratio of acrylic acid to triethylamine to dimethylacetamide was 1: 0.1: 2;
step two, the first step reaction: under the protection of inert gas and at the temperature of 5 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 3 hours;
step three, reaction in the second step: heating to 75 ℃, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding acrylic acid to be 2.5 h;
step four, reaction in the third step: and then introducing the rest hydrogen sulfide product, stirring for reaction for 4 hours, and then carrying out reduced pressure rectification to obtain the 3-mercaptopropionic acid.
In this example, the molar ratio of hydrogen sulfide from a portion of the hydrogen sulfide product in step two of the second step to the remainder of the hydrogen sulfide product in step four was 2: 1.
Example 3.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps:
first, the pressure swing adsorption method purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then carrying out flash evaporation on the liquid phase, carrying out first separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesizing 3-mercaptopropionic acid
Step one, material selection: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent; in this example, the molar ratio of acrylic acid to hydrogen sulfide in the hydrogen sulfide product was 1: 4; in this example, the molar ratio of acrylic acid to triethylamine and dimethylacetamide was 1: 0.4: 5;
step two, the first step reaction: under the protection of inert gas and at the temperature of 15 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 2 hours;
step three, reaction in the second step: heating to 85 ℃, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding acrylic acid to be 1.5 h;
step four, reaction in the third step: then the rest hydrogen sulfide product is added, stirred and reacted for 6 hours, and then the 3-mercaptopropionic acid is obtained after reduced pressure rectification.
In this example, the molar ratio of hydrogen sulfide from a portion of the hydrogen sulfide product in step two of the second step to the remainder of the hydrogen sulfide product in step four was 3: 1.
Example 4.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps:
first, the pressure swing adsorption method purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then, carrying out flash evaporation on the liquid phase, carrying out primary separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesizing 3-mercaptopropionic acid
Step one, selecting materials: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent; in this example, the molar ratio of acrylic acid to hydrogen sulfide in the hydrogen sulfide product was 1: 2; in this example, the molar ratio of acrylic acid to triethylamine to dimethylacetamide was 1: 0.0.3: 2.5;
step two, the first step reaction: under the protection of inert gas and at the temperature of 8 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 2.8 hours;
step three, reaction in the second step: heating to 78 ℃, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding the acrylic acid to be 2.3 h;
step four, reaction in the third step: and then the rest hydrogen sulfide product is introduced, stirred and reacted for 4.5 hours, and then the 3-mercaptopropionic acid is obtained through reduced pressure rectification.
In this example, the molar ratio of hydrogen sulfide from the portion of the hydrogen sulfide product in step two of the second step to the hydrogen sulfide from the remainder of the hydrogen sulfide product in step four was 2.2: 1.
Example 5.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps:
first, the pressure swing adsorption process purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then carrying out flash evaporation on the liquid phase, carrying out first separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesis of 3-mercaptopropionic acid
Step one, selecting materials: taking acrylic acid and a hydrogen sulfide product obtained in the first step as raw materials, triethylamine as a catalyst and dimethylacetamide as a solvent; in this example, the molar ratio of acrylic acid to hydrogen sulfide in the hydrogen sulfide product was 1: 2.5; in this example, the molar ratio of acrylic acid to triethylamine and dimethylacetamide was 1: 0.3: 4;
step two, the first step reaction: under the protection of inert gas and at the temperature of 12 ℃, the mixed solution of triethylamine and dimethylacetamide and part of hydrogen sulfide products are stirred and react for 2.2 hours;
step three, reaction in the second step: heating to 82 ℃, then dropwise adding acrylic acid for reaction, and controlling the time for dropwise adding acrylic acid to be 1.8 h;
step four, reaction in the third step: and then the rest hydrogen sulfide product is introduced, stirred and reacted for 5.5 hours, and then the 3-mercaptopropionic acid is obtained through reduced pressure rectification.
In this example, the molar ratio of hydrogen sulfide from the portion of the hydrogen sulfide product in step two of the second step to the hydrogen sulfide from the remainder of the hydrogen sulfide product in step four was 2.8: 1.
Practical application examples.
A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas comprises the following steps: after the air in a 1000ml high-pressure reaction kettle is replaced by nitrogen for three times, 20.2g of triethylamine and 304.5g of dimethylacetamide are added, stirred and cooled to 10 ℃, and the temperature is controlled to be 10 +/-5 ℃. Introducing 34g of purified hydrogen sulfide, reacting for 2h, discharging excessive hydrogen sulfide gas, absorbing with alkali, raising the temperature to 80 ℃, adding 72g of acrylic acid into the reaction kettle within 2h, continuously introducing 68g of hydrogen sulfide, and reacting for 5 h. The obtained reaction liquid is directly stripped to obtain 68g of a mixture of triethylamine and dimethylacetamide under normal pressure, then high vacuum rectification is carried out to collect 228.9g of dimethylacetamide at the temperature of 80-110 ℃, and distillation is carried out to collect 69g of 3-mercaptopropionic acid at the temperature of 110-130 ℃, wherein the content is more than or equal to 99.0%, the yield is 65.09%, and the high-boiling residue is thiodipropionic acid.
Although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention.

Claims (1)

1. A method for synthesizing 3-mercaptopropionic acid by using acidic waste gas is characterized by comprising the following steps: the method comprises the following steps:
first, the pressure swing adsorption process purifies the hydrogen sulfide in the acid waste gas
Cooling and pressurizing the acid gas to liquefy part of the gas, wherein methane and nitrogen are still gas, and removing the methane and nitrogen after gas-liquid separation; then carrying out flash evaporation on the liquid phase, carrying out first separation on the hydrogen sulfide and the carbon disulfide, and introducing the mixture of the hydrogen sulfide and the carbon disulfide subjected to flash evaporation into a rectifying tower for rectification to obtain a hydrogen sulfide product with the content of more than 99.5%;
second step, synthesizing 3-mercaptopropionic acid
Replacing air in a 1000ml high-pressure reaction kettle with nitrogen for three times, adding 20.2g of triethylamine and 304.5g of dimethylacetamide, stirring and cooling to 10 ℃, controlling the temperature to be 10 +/-5 ℃, introducing 34g of hydrogen sulfide purified in the first step, reacting for 2 hours, discharging excessive hydrogen sulfide gas, absorbing with alkali, raising the temperature to 80 ℃, introducing 72g of acrylic acid into the reaction kettle within 2 hours, continuously introducing 68g of hydrogen sulfide, reacting for 5 hours, directly stripping the obtained reaction liquid, obtaining a mixture of triethylamine and dimethylacetamide under normal pressure, rectifying under high vacuum to collect 80-110 ℃ fraction as dimethylacetamide, and fractionating to collect 110-130 ℃ fraction as 3-mercaptopropionic acid.
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CN112409227B (en) * 2020-11-30 2023-01-20 益丰新材料股份有限公司 Method for efficiently synthesizing 3-mercaptopropionic acid
CN112608259B (en) * 2020-12-26 2022-12-06 益丰新材料股份有限公司 Synthetic method of 3-mercaptopropionic acid

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