Cooperative Structure-Directing Effects in the Synthesis of a High-Silica Zeolite Mazzite Analogue

A zeolite Mazzite (MAZ) analogue with high silica content has been synthesized from a Na2O-Al2O3-SiO2-morpholine-H2O system. The crystal morphology of this MAZ analogue was found to consist of spherical agglomerates of diameter up to 17 μm. It has been unequivocally demonstrated that zeolite Mordenite (MOR) or amorphous material was produced instead in the absence of either morpholine or Na+. Associated phases indicate that the MAZ may be a “intermediate phase” between the crystallization fields of zeolites Analcime (ANA) and MOR. Thus, the zeolite MAZ analogue is seemingly derived from the cooperative structure-directing effect of the organic molecule morpholine and the inorganic cation Na+. The results of CHN elemental analyses as well as of thermogravimetric (TG) analyses confirmed that morpholine had been incorporated into the zeolitic structure.