Temperature Effect on the Chromatographic Separation of Lutetium-177 and Ytterbium

It was experimentally established that an increase in the temperature in the range of 20–90°C improves the parameters of Lu/Yb chromatographic separation on the Dowex 50WX8 cation exchanger with the α-HIBA eluent (0.125 M, pH 4.3). An increase in the temperature leads to a decrease in the height of the equivalent theoretical plate (HETP) from 7.7 to 0.6 mm for Yb and from 1.1 to 0.3 mm for Lu, to an increase in resolution between peaks from 0.6 to 1.7, and a change in Yb peak asymmetry from 2.1 to 0.4. The temperature dependences of the retention volumes are well described by the Van’t Hoff equation (R2 = 0.99). The observed 1.8-fold peak broadening for Yb and 2.4-fold for Lu is accompanied by a decrease in the maximum yield in fractions from 14.4 to 5.5% for Lu and from 5 to 3% for Yb.