SYNTHESIS AND CHARACTERIZATION OF ZEOLIT ZSM-5 AT LOW TEMPERATURE USING NATURAL SILICA PRECURSOR

• Main Author: Andre Fabiani, Verry
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/32600
• Institution: Institut Teknologi Bandung

Zeolite ZSM-5 has been well-known as catalyst in the petrochemical industry. The synthesis of ZSM-5, however has to be optimized since hydrothermal method applies a non environmental friendly method. In order to outcome this drawback, synthesis at low temperature using natural silica precursor was offered and consideredn to be facile and effective strategy. The concept of green synthesis strategy is not only about setting up the reaction condition but also utilizing eco-compatible chemicals and the reduction of used organic structure directing agent (OSDA). Herein, we have demonstrated that green synthesis of ZSM-5 can be carried out using natural silica precursor. Amorphous rice husk (RH) was utilized as an alternative silica source for the synthesis of ZSM-5. Silica source from rice husk can be extracted without applying any combustion. Extraction of silica from rice husk can produce about 70-80 % purity silica. Reduction of tetrapropylammonoim bromide (TPABr) as OSDA for the synthesis of ZSM-5 was also carried out. The starting molar composition was done following recipe of 0.07Na2O: 1SiO2: 0.005Al2O3: xTPABr: 11.69 H2O with x = 0 ; 0.015 ; 0.045 ; 0.086. The mixture was heated at 90 ºC under static condition for 4 d. For comparison, sample prepared using hydrothermal treatment under high temperature and autogeneous pressure with the autoclave apparatus was also done. The results show that the reaction of RH with TPABr at low temperature and under atmospheric pressure led to the successful transformation of amorphous into crystalline phase of ZSM-5. We have shown that non-combusted RH can be used as natural silica precursor in the synthesis of ZSM-5 zeolite at low-temperature with the reduction of OSDA. Synthesis ZSM-5 at low temperature can be regarded as simple, low-cost, and less-harmful technique comparing to the conventional one.