Phenol ketone products

Plastic rubber

Current Location： Home > News > Chemical Knowledge > Production and manufacturing method and process of terephthalic acid

[Chemical Knowledge]：Production and manufacturing method and process of terephthalic acid

Read： 1071 Time：12months ago Source：Transform the World with Simplicity

Terephthalic acid (PTA) is an important organic chemical raw material, which is widely used in the production of polyester fiber, polyester resin, film and other products. In the field of raw materials for chemical production, there are two main methods for manufacturing terephthalic acid: oxidation and esterification. This article will detail these two manufacturing methods.

1. oxidation

oxidation is the main production method of terephthalic acid, including liquid phase oxidation and gas phase oxidation.

1. liquid phase oxidation method

liquid phase oxidation method is at high temperature and high pressure, the xylene mixed with acetic acid, into the air oxidation reaction, the generation of terephthalic acid and acetic acid. During the reaction, it is necessary to add catalysts and stabilizers to promote the reaction and control the formation of by-products. After completion of the reaction, purified terephthalic acid is obtained by steps such as crystallization, filtration, and drying. The advantages of

liquid phase oxidation method are mature process, stable operation, and high quality terephthalic acid can be produced. However, this method needs to use a large amount of acetic acid as a solvent, the production cost is high, and the equipment corrosion is serious.

2. gas phase oxidation method

gas phase oxidation method is in high temperature, high pressure, the xylene and oxygen gas phase oxidation reaction, the generation of terephthalic acid and carbon dioxide. This method requires the use of a catalyst, and metal oxides such as vanadium and titanium are usually used as the catalyst. After completion of the reaction, pure terephthalic acid is obtained by condensation, separation and the like. The advantages of

gas phase oxidation method are that the reaction conditions are relatively mild, do not need to use a large amount of solvent, and the production cost is low. However, the catalyst activity of this method is high, it needs to be replaced regularly, and the requirements for equipment are high.

2. Esterification

Esterification is another production method of terephthalic acid, which mainly involves the transesterification of dimethyl terephthalate with methanol to produce terephthalic acid and methanol. The process requires the use of a catalyst, typically an acidic catalyst such as sulfuric acid, hydrochloric acid, and the like. After the completion of the reaction, purified terephthalic acid is obtained by steps such as distillation and crystallization. The advantages of

esterification method are simple process, convenient operation, and high quality terephthalic acid can be produced. However, this method requires the use of a large amount of methanol as a solvent, the production cost is high, and a large amount of by-product methanol is produced, which requires recovery treatment.

In summary, oxidation and esterification are both common manufacturing methods of terephthalic acid, and each has its advantages and disadvantages. In actual production, a suitable manufacturing method should be selected according to the specific situation to obtain high-quality terephthalic acid and reduce production costs.

Previous： Production and manufacturing method and process flow of p-chlorotoluene

Next： The production and manufacturing method and process flow of benzene two nitrile.

News Categories