Based on the obtained results, it can be concluded that a miniaturized U-shaped hollow fiber contactor operated in
recirculation mode can be used efficiently for the re-extraction of Lu(III) from the organic phase, for the purpose of its
recovery. The removal of Lu(III) achieved in the current module was insufficient for commercial applications and the
higher removal efficiencies (above 95%) could be achieved using either a hollow fiber contactor with a larger membrane
area or a two-stage process.