REDUCTION OF MAGADIITE CRYSTALLINE PHASE IN THE SYNTHESIS OSDA FREE ZEOLITE ZSM-5

• Main Author: ERIKA NIM: 10513002, DENANTI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/26475
• Institution: Institut Teknologi Bandung

Zeolite ZSM-5 is one of the most widely used catalysts because it has good thermal even mechanical stability, and high acidity amount. Conventionally, synthesis zeolite ZSM-5 using organic compounds as structure directing agents (OSDA) based on quaternary ammonium cations such as TPABr (Tetra propylammonium Bromide). However, the synthesis of these zeolites is considered not environmentally friendly because it can produced carbon emission from calcined so the concept of synthesis without using OSDA is important to develop. Problems that occur in synthesis without using OSDA is the discovery of another phase, magadiite. Magadiite more easily formed than ZSM-5 because it has simpler structure. In this study, we studied the formation of magadiite phase in the crystallization of zeolite ZSM-5 OSDA free with the purpose of knowing the influence of chemical composition and hydrothermal conditions. By knowing this state, the strategy for purification of magadiite can be known. ZSM-5 is synthesized using basic materials such as Cab-O-Sil, NaOH, Al(OH)3 and water. The zeolite structure is determined by X-ray diffraction (XRD) and infrared spectroscopy (ATR-IR). Synthesis with Si/Al molar ratio = 25; NaOH/Si = 0,2; H2O/Si = 20 at 160 °C gives ZSM-5 with magadiite mixture. The results from optimization of alkalinity and hydrothermal conditions indicate that the magadiite intensity of the diffractogram is inversely proportional to the ratio of NaOH/Si, and is directly proportional to the time of synthesis and time of aging. Zeolite ZSM-5 successfully synthesized with maximum crystalline yield at NaOH/Si molar ratio 0,2, aging time 72 hours, and synthesis time 96 hours. It shows that magadiite cannot be purified only by optimizing the chemical composition and hydrothermal conditions.