Facile synthesis of highly crystalline EMT zeolite by hydrothermal conversion of FAU zeolite in the presence of 1,1’-(1,4-butanediyl)bis(1-azonia-4-azabicyclo [2,2,2]octane) dihydroxide

Hydrothermal conversion of cubic (FAU) zeolite into hexagonal (EMT) zeolite using 1,1’-(1,4-butanediyl)bis (1-azonia-4-azabicyclo [2,2,2]octane) dihydroxide ([Dab-4]2+(OH)2) instead of 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6), a well-known organic structure-directing agent (OSDA) for the synthesis of EMT zeolite, was investigated. A systematic study concerning hydrothermal synthesis parameters such as H2O/SiO2, NaOH/SiO2, and [Dab-4]2+(OH)2/SiO2 ratios in the starting synthesis mixture, and temperature and time of synthesis revealed that pure, highly crystalline EMT zeolite can be easily obtained within a short crystallization period of 6 h.