Studies of Benzalkonium Chloride Micelle Formation as Mesoporogen in Pre-synthesis of Hierarchically Porous ZSM-5 Zeolite

• Main Author: Sutarma, Dedi
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/32273
• Institution: Institut Teknologi Bandung

Zeolite is one of the catalysts which is widely used in various industrial processes. Although there has been intensive research on the zeolite, formation of zeolite framework still leaves a lot of questions. This study is a continuation of the successfully synthesized hierarchically porous ZSM-5 zeolite using benzalkonium chloride. Benzalkonium chloride in the presynthesis interacts as zeolite precursors by forming micellar liquid crystal. These argument were proved through the study of aggregation kinetics on zeolite precursors, zeolite precursor bulk phase analysis, the value of Critical Micellar Concentration (CMC) and phase-transition temperature of benzalkonium chloride. Critical Micellar Concentration (CMC) was found at 1.8 mM which lies below the concentration of benzalkonium chloride used in the synthesis of zeolite. Observation on changes in the value of conductivity due to temperature rise on benzalkonium chloride showed the liquid crystal phase transition of benzalkonium chloride at 35.6 oC. Addition of 4 mM NaOH to micellar solution pointed the increase in phase transition temperature to 36.5 oC. It shows a tendency of the liquid crystal stabilization by introducing ions to micellar solution. This research also performed determination of the mean aggregation number of benzalkonium chloride micelles using Fluorescence Quenching method (FQ) which can be used to determine the morphology of benzalkonium chloride micelles. Anthracene sulfonate was used as a probe and CTAB (Cetyl Trimethyl Ammonium Bromide) surfactant as quencher. The value of aggregation number obtained from the experiment was 90. Thus, benzalkonium chloride micelles can be regarded as spherical. Aggregation number of benzalkonium chloride is also associated with the formation of macropores at ZSM-5 zeolite with spherical morphology in SDA-free synthesis of ZSM-5