The Production Process of 3-AMINO-1,2-PHTHALIC ACID, DIMETHYL ESTER

The production process of 3-amino-1,2-phthalic acid, dimethyl ester, also known as 3-APA, involves several steps, from the preparation of raw materials to the final product.
The following is an overview of the production process of 3-APA, dimethyl ester in the chemical industry.

1. Preparation of raw materials: The production of 3-APA, dimethyl ester begins with the preparation of raw materials, which includes the reaction of dimethyl terephthalate with ammonia to produce 3-APA, followed by the esterification of 3-APA with methanol to produce 3-APA, dimethyl ester.
   
2. Reaction of dimethyl terephthalate with ammonia: The reaction of dimethyl terephthalate with ammonia is the first step in the production of 3-APA, dimethyl ester.
   In this step, dimethyl terephthalate is reacted with ammonia in the presence of a catalyst, such as sulfuric acid, to produce 3-APA.
   
3. Esterification of 3-APA with methanol: The next step in the production of 3-APA, dimethyl ester is the esterification of 3-APA with methanol.
   In this step, 3-APA is reacted with methanol in the presence of a catalyst, such as a strong acid, to produce 3-APA, dimethyl ester.
   
4. Purification of the product: After the esterification step, the product is purified to remove any impurities that may have been introduced during the reaction.
   This is typically done through a distillation process, in which the product is distilled to remove any impurities that have a lower boiling point.
   
5. Crystallization: The purified product is then crystallized to produce a pure form of 3-APA, dimethyl ester.
   This is typically done by allowing the purified product to cool, causing it to crystallize.
   
6. Recovery of the product: The final step in the production of 3-APA, dimethyl ester is the recovery of the product.
   This is typically done through a process known as solvent extraction, in which the product is extracted from the crystallized form using a solvent, such as ether or hexane.
   

In conclusion, the production process of 3-APA, dimethyl ester is a multi-step process that involves the reaction of dimethyl terephthalate with ammonia, esterification of 3-APA with methanol, purification of the product, crystallization and recovery of the product.
This process is used to produce 3-APA, dimethyl ester, which is a key intermediate in the production of a variety of chemical products, including dyes, plastics, and pharmaceuticals.