A new LPCE column (LPCE-3) of 2 m packing height and 50 mm inner diameter expands the experimental potential of “EVIO” pilot plant. Fresh RCTU-3SM catalyst of somewhat greater average percentage of Platinum and a little larger dimension of SDBC carrier has been tested in LPCE-3. Both hydraulic and isotope separation characteristics of LPCE-3 filled with alternating layers of the catalyst and packing in the volume ratio of 1:4 (the same packing and ratio which are used in LPCE-1 and LPCE-2 columns) have been studied. The experimental results are presented in comparison with ones received on LPCE-1 and LPCE-2 earlier. This paper aims to the problem of comparing different columns operated at dissimilar conditions and separating different isotopes. In the search for an invariant, which would unambiguously present performance of LPCE, it is experimentally shown that performance expressed by a 3-fluid model characteristic, Kc – mass-transfer coefficient for catalytic exchange (at fixed mass-transfer coefficient for phase exchange) is the same for different isotopes and different temperatures in contrast to the overall mass-transfer coefficient, Kya.