Effect of Aging on the Precursor Sol for the Synthesis of Nanocrystalline ZSM-5

Nanocrystalline ZSM-5 (Si/Al = 100) is synthesized from an initial clear solution of TEOS-TPAOH-AIP-H2O system. The method comprises three stages: (i) concentration of an initial clear solution, (ii) low-temperature aging (25°C, 50°C, 75°C, or 100°C), and (iii) high-temperature hydrothermal treatment (180°C for 90 min). The average size of the crystals is almost the same when the aging temperature is in the range from 25°C to 75°C, i.e., around 48 nm. However, the average size of the zeolite crystals increases as the aging temperature reached 100°C, to 85 nm.