SYNTHESIS AND CHARACTERISATION OF SOD-, CAN- ANDJBW-TYPE STRUCTURES BY HYDROTHERMAL REACTION OFKAOLINITE AT 200OC

摘要

Low-silica zeolitic materials like SOD, CAN and JBW crystallized after hydrothermal transformation ofkaolinite in the system Na2O-Al2O3-SiO2-H2O at 200°C, with or without the addition of a structure-directing agent. Thesynthesis products were characterized by XRD, SEM, FTIR, 29Si and 27Al MAS-NMR and TGA. After dissolution of kaolinitein alkaline medium, co-crystallization of SOD and CAN, likely via a metastable LTA intermediate, was followed by atransformation to JBW-type structure.