FIELD: radio-pharmaceutical preparations. SUBSTANCE: process is carried out as multiple extraction with the same small amount of extractant for one radionuclide isolation act owing to introducing, along with primary extraction column, a supplementary one so that the two columns may communicate with each other and be alternately involved in extraction process. Position of water-organic interphase boundary is dynamically controlled by adding additional amount of aqueous phase or overflowing excess aqueous phase from additional column into primary one at the moment when extractant is picked off. EFFECT: enhanced extraction efficiency, decreased installation size, and improved reliability of operation. 3 cl, 1 dwg
