PURIFICATION OF NON-PROTEIN NITROGEN COMPONENT AND PURIFIED MATERIAL

摘要

PURPOSE:To provide the subject purification method capable of efficiently producing highly purified non-protein nitrogen components (NPN) in a short time. CONSTITUTION:An NPN-containing raw material is subjected to electrodialysis desalting treatment using an ion-exchange membrane exhibiting a low NPN- blocking ratio to obtain a desalted NPN mother liquor and a concentrated recovery salt solution (A). The resultant desalted NPN mother liquor is treated with an ion-exchange resin so as to adsorb NPN on the resin. The adsorbed NPN is then eluted and an NPN fraction (B) is obtained. After (A) and (B) are mixed and neutralized, an electrodialysis desalting treatment is applied thereto by using an ion-exchange membrane exhibiting a high NPN-blocking ratio. Thus, the objective NPN is purified.