The production process of DINP and its main raw materials

Diisononyl phthalate (DINP) is a plasticizer commonly used in the production of various plastic and polymer products. It imparts flexibility and durability to plastics, making it suitable for applications such as vinyl flooring, automotive parts, wire and cable insulation, and more. The production of DINP involves a chemical synthesis process, and its main raw materials are typically isononanol and phthalic anhydride. Here's an overview of the production process of DINP:

Raw Materials:

Isononanol (INA): Isononanol is an alcohol derived from a petrochemical feedstock, typically a C9 fraction, which consists of hydrocarbons containing nine carbon atoms. It is a key raw material in the production of DINP.

Phthalic Anhydride (PA): Phthalic anhydride is an organic compound that serves as the other primary raw material for DINP production. It is derived from the oxidation of o-xylene or naphthalene.

Production Process:

The production of DINP involves a two-step esterification process:

Step 1: Esterification Reaction

In this step, isononanol (INA) reacts with phthalic anhydride (PA) to form a diester known as diisononyl phthalate (DINP). The reaction is catalyzed by an acid catalyst, typically sulfuric acid. The chemical equation for this reaction is as follows:

During this esterification reaction, water is generated as a byproduct and is usually removed from the reaction mixture.

Step 2: Distillation and Purification

After the esterification reaction, the reaction mixture is typically subjected to distillation to separate and purify the DINP product from impurities and unreacted raw materials. Distillation separates the DINP from lower boiling-point components, including unreacted isononanol and phthalic anhydride, as well as other impurities.

The purified DINP product can then be further processed or blended with other additives as needed for specific applications in the plastics and polymer industry.