Comparative Equilibrium Studies for Citric Acid by Amberlite LA-2 or Tridodecylamine (TDA)

Carboxylic acids like citric acid are produced by fermentation. They have been used in many industrial fields as intermediate and starting materials, and their importance is still growing. It is important to separate them from the fermentation broth. In this sense, comparison of different types of solvents and amines for extraction of carboxylic acids from the fermentation broth and the most effective amine-solvent composition is sought. Studies have been performed on the extraction of citric acid from fermentation broth by tridodecylamine (TDA) (a long chain tertiary amine), and Amberlite LA-2 (a secondary amine mixture). These extractants were dissolved in different solvents having different chemical structures. The extractions were carried out at 298 K. Comparison of the results were made using the distribution coefficient, loading factor, separation factor, and the percentage of extraction yield. The most effective solvent was determined as 1-octanol for both TDA and Amberlite LA-2 with a distribution value of 29.63 and 103.80, respectively. The maximum value of the extraction efficiency was found to be 99.05 % with Amberlite LA-2 in 1-octanol.