Facile Hydrothermal Synthesis of EAB‐Type Zeolite under Static Synthesis Conditions

Conventionally, EAB‐type zeolites are crystallized by hydrothermal synthesis for many days under agitational synthesis conditions such as rotation or stirring. In the present study, EAB‐type zeolite is obtained by hydrothermal synthesis within 12 h under static synthesis conditions for the first time. The effects of crystallization temperature, aging of the precursor sol, and addition of seed crystals are investigated. The results reveal that EAB‐type zeolite can be obtained when using a precursor sol with short aging time followed by hydrothermal synthesis in a very narrow temperature range 110 °C−120 °C under static synthesis condition. Addition of seed crystals is found to suppress the formation of SOD‐type zeolite, the primary phase at high hydrothermal synthesis temperatures, while it does not increase the crystallization rate of EAB‐type zeolite. Furthermore, the crystallization behavior at 120 °C is examined by varying the synthesis time. EAB‐type zeolite with invariably twinned plate‐like morphology starts to crystallize between synthesis time of 3 to 6 h at 120 °C under the static synthesis condition. EAB‐type zeolite is synthesized under static synthesis conditions, for the first time. Narrow hydrothermal synthesis temperature range and short aging time are found to be key factors. Addition of seed crystal restricts the formation of impurity phases. Crystallization behavior at 120 °C shows EAB‐type zeolite can be crystallized within 12 h, which is the shortest synthesis time reported.