EXTRACTION OF L-LYSINE FROM ITS DILUTE AQUEOUS-SOLUTIONS BY ROTATING FILM PERTRACTION

Removal and concentration of L-lysine in a three liquid phase pertraction system was studied using a laboratory three stage rotating disk pertractor. A 5% (vol) solution of Di-2-ethyl hexyl phosphoric acid (D2EHPA) in normal paraffins was used as an intermediate membrane liquid. The amino acid was extracted from its dilute aqueous solution (feed F) and concentrated in the stripping liquid R-a 1N solution of HCI in water. D2EHPA dissolved in the membrane liquid played the role of a ion exchange carrier. It was found that the most important parameters controlling the efficiency of this continuous pertraction process are the speed of disk rotation and the feed solution flowrate. The counter-current flow arrangement in the apparatus and the high flowrate ratio chosen provided nearly complete removal of solute from the feed as well as a concentrated solution of L-lysine.