What are the common by-products in the production of acetic acid?

What are the common by-products in the production of acetic acid?

As an important organic compound, acetic acid is widely used in chemical industry, food, medicine and other fields. In the production process of acetic acid, due to the different reaction conditions and processes, some by-products will be produced. These by-products not only need to be disposed of properly, but may also have an impact on production efficiency and the environment. In this paper, the common by-products in the production of acetic acid will be analyzed in detail, and the treatment methods will be discussed.

1. By-product of acetic acid production by fermentation

fermentation is a traditional method of acetic acid production, mainly by acetic acid bacteria for ethanol oxidation fermentation. In this process, in addition to acetic acid, some by-products are produced. For example:

• carbon Dioxide: Ethanol is oxidized during the fermentation process, and carbon dioxide is released while generating acetic acid. This part of the gas needs to be treated by the absorption device to avoid pollution to the environment.
• Water: A certain amount of water will be produced during the fermentation process, which needs to be purified before being discharged to prevent pollution to the water body.
• Organic acid: During the fermentation process, small amounts of other organic acids, such as lactic acid and butyric acid, may be produced. If these substances are not treated, they may affect the quality of acetic acid and even cause corrosion to production equipment.

2. By-product of acetic acid production by oxidation method

oxidation is an important method for the production of acetic acid, usually using ethanol in the presence of a catalyst for oxidation reaction. The by-products of this process mainly include:

• water: The oxidation reaction will produce a large amount of water, which needs to be treated before it can be discharged.
• sulfuric acid ester: If sulfuric acid is used as a catalyst, sulfuric acid ester may be produced as a by-product after the reaction. These sulfuric acid esters need to be neutralized to prevent environmental pollution.
• Other Organics: In the oxidation process, some incomplete organic compounds may be generated, such as acetaldehyde and formaldehyde. If these substances are not treated, they may affect the purity of acetic acid and even cause harm to human health.

3. By-product of acetic acid production by ethylene oxidation

ethylene oxidation is a more advanced acetic acid production method, and its by-products mainly include:

• acid insoluble matter: The oxidation of ethylene may produce some acidic insolubles, such as silica and alumina. If these substances are not treated, they may block the equipment and affect the production efficiency.
• Other Organics: During the reaction process, some incomplete organic compounds may be generated, such as acetaldehyde and formaldehyde. These substances need to be separated and treated to ensure the quality of acetic acid.
• Tail gas: Ethylene oxidation reaction will produce a large amount of tail gas containing acid gases, such as carbon dioxide and sulfur dioxide. These gases need to be treated before they can be discharged to prevent pollution to the environment.

4. Treatment of tail gas and waste liquid

in addition to the above by-products, a large amount of tail gas and waste liquid are also produced in the acetic acid production process. These substances, if left untreated, may cause serious pollution to the environment. For example:

• tail gas treatment tail gas usually contains acid gas and organic pollutants, which need to be treated by washing, adsorption and catalytic oxidation to reduce the emission concentration of pollutants.
• waste liquid treatment waste liquid usually contains unreacted raw materials, catalysts and by-products, which need to be treated by neutralization, precipitation and evaporation to realize the recycling of resources.

5. Resource utilization of by-products

in order to achieve the goal of green chemical industry, the by-products produced in the production of acetic acid can be used as resources. For example:

• carbon Dioxide carbon dioxide can be used as an industrial raw material, for example in the production of urea and carbonated beverages.
• sulfuric acid ester sulfate ester can be converted into sodium sulfate by neutralization reaction, which is used to make detergent and cellophane.
• waste liquid: The organic matter in the waste liquid can be converted into clean energy such as biogas through fermentation and oxidation treatment.

6. Summary

common by-products in the production of acetic acid include carbon dioxide, water, organic acids, sulfuric acid esters, acidic insolubles and other organics. These by-products need to be treated through scientific treatment methods to reduce the impact on the environment and realize the recycling of resources. With the continuous development of green chemical technology, the treatment and resource utilization of by-products in the production of acetic acid will become more efficient and environmentally friendly.