An ambient pressure method for synthesizing NaY zeolite

Zeolites are vital industrial materials applied widely in the field of heterogeneous catalysis. Porous zeolites are essentially synthesized in the presence of soft or hard templates in processes such as hydrothermal, solvothermal, and ionothermal synthesis. Herein, we demonstrated a facile ambient pressure technique to synthesize NaY zeolite using a glass tube as a reactor and a fluid sealant to create a physical barrier between the reactor contents and the atmosphere. The synthesized zeolite Y was characterized by XRD, SEM, TEM, UV-Raman, N2 sorption, MAS NMR, and XRF spectroscopy. In comparison to the traditional hydrothermal synthesis routes, the avoidance of high-pressure synthesis apparatus not only reduces safety risks but also significantly improves the yield of zeolite products with a crystallinity of 52% and Si/Al = 3.51. Furthermore, the process is leaner, efficient, and reduces costs. Optimum conditions realized for the synthesis of highly crystalline zeolite Y were 90 °C and 18 h crystallization temperature and period respectively, using 1-dodecanol as a sealant. Subsequently, PEG6000 emerged the best among organic templates investigated to improve porosity while maintaining high crystallinity of the zeolite.