The use of ion exclusion chromatography as approved to the normal ion exchange chromatography to achieve a more efficient lysine recovery from fermentation broth

Ion exclusion chromatography was used to recover lysine from a fermentation broth in order to investigate possible replacements for conventional waste-generating ion exchange processes. The fermentation broth was pretreated with a microfiltration process. The permeate solution was adjusted to the isoelectric pH of lysine to convert lysine to the nonionic form and fed to a column packed with a monodisperse cation exchange resin of the NH4+-form. Distilled water was used as the elution agent. Excluded ionic impurities such as sulfate ion were eluted first, followed by lysine. The separation efficiency and lysine recovery were improved using a smaller feed volume, a lower flow rate, and an elevated temperature.