Regarded as the most crucial dicarboxylic acid in industrial practice, Adipic acid is rarely found in nature and is instead produced in a white, crystalline powder as a precursor for nylon production. It is produced from a ketone-alcohol (KA) oil of cyclohexanol and cyclohexanone, which is then oxidized with nitric acid to produce Adipic Acid.
Found in beets and sugar cane naturally, Adipic acid was not of much interest to chemists until 1939, when Wallace Carothers invented nylon. Researchers learned of the role Adipic Acid played in reacting to produce nylon 606, and thus they needed to find a way to mass produce the chemical. After successfully producing it from KA oil, more than 5.7 billion pounds of Adipic Acid are produced annually worldwide.