Separation of trivalent actinides from lanthanide fission products can be done by a cation-exchange resin column using a 90% water/10% ethanol solution saturated with hydrochloric acid (HCl) as eluant. It is usually followed by anion-exchange chromatography using 6 molar HCl as eluant. A cation-exchange resin column (Dowex-50 exchange column) treated with ammonium salts is then used to separate fractions containing elements 99, 100 and 101. These elements can be then identified simply based on their elution position/time, using α-hydroxyisobutyrate solution (α-HIB), for example, as eluant.