Preparation and characterization of LiCl-occluded LiLSX zeolite

LiCl-occluded LiLSX (Li exchanged Low Silica X zeolite with Si/Al = 1.0) was prepared by a heat treatment after evaporating a LiLSX or NaLSX slurry with LiCI, followed by lithium exchange in the case of NaLSX. The amount of occluded LiCl increased with increasing of the temperature. LiCl-occluded LiLSX prepared from NaLSX had a higher crystallinity than that prepared from LiLSX. The difference in crystailinity is explained as being related to the difference in the distortion of the skeleton structure of the zeolites. Chloride anions in high-crystallinity LiCl-occluded LiLSX were found to be located in sodalite cages by a Fourier synthesis of the powder X-ray diffraction pattern. The location of lithium cations was investigated based on the adsorption properties of nitrogen at room temperature and existing data on salt-occluded zeolites. Lithium cations in LiCl-occluded LiLSX are thought to simultaneously occupy the adjacent sites I and 1'.