[en] Effective radiochemical scheme of preparation of carrier-free ¹³⁹Cs radionuclide from irradiated by deuterons ¹³⁹La target using extraction-chromatography separation of macroquantities of ¹³⁹La and ¹³⁹Cs in the trioctylamine-LiNO₃ system and additional purification of desired radionuclide in HDEHP-HNO₃ extraction-chromatography system. Carrier-free ¹³⁹Cs radionuclide is prepared in 11 mCi quantity by reprocessing of irradiated target and that is 80.8 % of theoretically calculated quantities. Factor of purification from lanthanum is 10³