MULTI-COMPONENT ADSORPTION BEHAVIOR OF HYDROGEN ISOTOPES ON ZEOLITE 5A AND 13X AT 77.4 K

摘要

Equilibrium isotherms for the adsorption of H_2, HD, HT, D_2, DT and T_2 on synthetic zeolite type 5A or 13X at 77.4 K are estimated by using a theoretical formula, where the isotopic difference in adsorption depends on the zero-point energy difference between hydrogen isotopes. The formula agrees with the experimental isotherms for H_2 and D_2 on the zeolites. Adsorption of H_2-D_2 and H_2-HD-D_2 mixtures on the same adsorbents is experimentally examined. The experiments are performed using a volumetric apparatus and a quadra-pole-type mass spectrograph. The experimental adsorption behavior of H_2, D_2 and HD shows agreement of separation factors with results calculated according to the ideal adsorbed solution theory describing multi-component behavior, where the equilibrium isotherms estimated for H_2, HD and D_2 are used. Based on the theoretical adsorption model, the multi-component behavior of HT, DT and T_2 is predicted here.