Immobilization of Large, Aliovalent Cations in the Small-Pore Zeolite K-Natrolite by Means of Pressure


  • This work was jointly supported by the Nuclear R&D program and the Global Research Laboratory program of the National Research Foundation of the Korean Ministry of Education, Science, and Technology (MEST). The authors thank Dr. Hyun-Hwi Lee for the operation of the 5A beamline at PAL. Experiments at PAL were supported in part by the MEST and POSTECH.


original image

High-pressure ion exchange of small-pore zeolite K-natrolite allows immobilization of nominally non-exchangeable aliovalent cations such as trivalent europium. A sample exchanged at 3.0(1) GPa and 250 °C contains about 4.7 EuIII ions per unit cell, which is equivalent to over 90 % of the K+ cations being exchanged (see picture).