METHOD FOR PREPARING L-LYSINE Russian patent published in 2004 - IPC

FIELD: chemical technology, amino acids. SUBSTANCE: invention relates to method for preparing L-lysine from lysine-containing solutions. Method involves treatment of racemate with L-tartaric acid to obtain salts of D- and L-lysine, removal of D-form, decomposition of lysine hydrotartrate by electrodialysis method in electrodialyzer device with alternating cation-exchange and bipolar membranes in intensive flow regimen by means of recharging L-lysine to cationic form. Electrodialysis process is carried out at current density from 12 to 18 mA/cm² and agent releasing from hydrotartrate is fed to the repeated stage for racemate separation. Method provides excluding the use of concentrated acid solution for ion-exchanger and a separating agent (L-tartaric acid) is used repeatedly and high separating coefficient of mixture from 950 to 1100. EFFECT: improved preparing method, enhanced effectiveness. 4 cl, 3 dwg, 3 ex