Liquid-Liquid Equilibrium Study of Phenol Extraction with Cyanex 923

Although phenol extraction with Cyanex 923 has widely been studied, liquid-liquid equilibrium between phenol and undiluted Cyanex 923 has not been thoroughly investigated. Many factors influence the phenol extraction with undiluted Cyanex 923. Increasing the phenol concentration causes a water molecule replacement in the extractant by phenol molecules. Increasing the pH value above 12 decreases the phenol distribution coefficient KD by 99.9%. A temperature increase from 15 degrees C to 65 degrees C results in a KD decrease of 70%. With increasing salt content KD increases due to salting-out. Adding organic acids stabilizes phenol in the aqueous phase and obstructs the extraction.