ABSTRACT The ion exchange chromatography technique was used for the enrichment of nitrogen 15 (15N). A set of columns filled with the ion exchange resin Wofatit KPS (medium porosity type) with 5.4 cm I.D. and 1.5 m height was set up. Ammonia NH4 +/NH3 aq. was chosen as the isotopic exchange system. The ammonium bands formed in the columns were eluted by a solution of sodium hydroxide. The isotope separation factor, ϵ, was found to decrease with increasing temperature or ammonia concentration. Operational conditions of temperature and ammonium concentration were proposed as the optimum for the production of the enriched isotope by using the present process. Results showed that: (1) the rear part of the band is enriched in 15N, while the frontal part is depleted; (2) it is possible to obtain 7.6 at. % of 15N after a 60 m displacement of the ammonium band. The analytical determination of the samples was made by emission spectrometry (NOI-6E).