Adipic Acid

Adipic Acid 

Adipic Acid (hexanedioic acid, C₆H₁₀O₄) is an important organic dicarboxylic acid, primarily used as a precursor for nylon 6,6 production. It is a white crystalline solid with mild acidity, soluble in water and alcohol.

Key Properties:

• Chemical Formula: HOOC(CH₂)₄COOH

• Molar Mass: 146.14 g/mol

• Melting Point: 152–154 °C

• Solubility: Water, ethanol, acetone.

• Biodegradability: Readily breaks down in the environment.

Production Methods:

1. Industrial Synthesis:

• Nitric Acid Oxidation: Cyclohexanol/cyclohexanone oxidized with HNO₃ (most common method).

• Bio-based Routes: Fermentation of glucose (sustainable alternative).

Major Applications:

1. Nylon 6,6 Production (~70% of global demand):

• Reacts with hexamethylenediamine to form polyamide.

2. Polyurethane Foams:

• Used as a chain extender.

3. Food Industry:

• Acidity regulator (E355) in beverages & gelatin.

4. Plasticizers & Lubricants:

• Ester derivatives (e.g., di-2-ethylhexyl adipate, DEHA).

5. Pharmaceuticals & Cosmetics:

• Buffer agent in tablets; controlled-release formulations.

Advantages & Challenges:

✔ High demand for nylon and biodegradable plastics.
✔ Emerging green production (bio-adipic acid from renewable feedstocks).
✖ Environmental concerns: Traditional HNO₃ oxidation releases N₂O (a potent greenhouse gas).