Focusing on the behavior of hydrogen isotopes onto synthetic zeolites (SZ) at cryogenic temperatures such as liquefied nitrogen, we have been developing a system of pressure swing adsorption (PSA) process for hydrogen isotope separation applicable to fusion fuel processing, environmental tritium safety confinement or recovery of tritium from heavy water reactors. We have previously reported the experimental results of successive isotope separation and enrichment in a H-2-D-2 mixture by the PSA process using a single column packed with SZ-5A. In this work, a PSA experiment using SZ-13X was carried out in a similar way to the previous experiment for comparing the functional adsorbents. The result shows that the PSA process operation with SZ-13X can make the performance of heavier isotope enrichment with efficiency at a factor of near twice in comparison to the same operation with SZ-5A.