Synthesis of LEV zeolite by interzeolite conversion method and its catalytic performance in ethanol to olefins reaction

The highly crystalline and pure LEV zeolite was obtained from the hydrothermal conversion of FAU zeolite as a crystalline aluminosilicate source in the presence of choline hydroxide. As LEV zeolite was not obtained from a conventional amorphous aluminosilicate gel, the advantage and uniqueness of the hydrothermal conversion of FAU zeolite was proven. The hydrothermal conversion of FAU zeolite into LEV zeolite depended significantly upon the Si/Al ratio of the starting FAU zeolite. Only the FAU zeolites with Si/Al ratios of 16–22 were converted into LEV zeolite. Most of all choline species as a SDA existed intact in zeolitic pores. As expected, the protonated LEV zeolite exhibited a good performance for conversion of ethanol to light olefins. The product yields were 35.8% of C2H4 and 34.4% of C3H6.