Hydrothermal transformation of magadiite into ferrierite in Al2O3-Na2O-ethylenediamine-H2O system

This study investigated the transformation of magadiite into ferrierite in Al2O3-Na2O-ethylenediamine (EDA)-H2O system. The influence of various parameters such as reaction temperature, time, alkalinity, the reactant Na2O/SiO2 ratio and EDA/SiO2 ratio were examined. Thermal and acid stability of the synthetic ferrierite are presented. Highly crystallized and pure ferrierite could be obtained from dispersion with the molar composition: 0.01 Na2O: 0.005 Al2O3: SiO2: 30 H2O: 20 EDA by heating at 433 K for 48 h. The structure of ferrierite was destroyed when the temperature rose above 873 K and the framework of the sample, stirred in 5 mol/L HCl for 3 h, is consistent with the untreated ferrierite.