FABRICATION OF NANOPOROUS SILICA USING PLURONIC P-123 AND F- 127 AS A SUPPORT FOR AU NANOPARTICLE CATALYST IN P-NITROPHENOL REDUCTION

• Main Author: Paradilah, Elsa
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/73360
• Institution: Institut Teknologi Bandung

Nanoporous silica is one of the development products in the field of nanotechnology which has good morphology, particle size, uniformity and dispersion hence can be applied as a catalyst, adsorbent and optical devices. Silica-based nanoporous can be differentiated based on the use of surfactants and their silica sources to produce different physicochemical properties. Nanoporous silica can be applied as a catalyst support for Au nanoparticles to prevent agglomeration of Au nanoparticles. One way to study the catalytic activity of Au nanoparticles is through the p-nitrophenol reduction. The pollutant p-nitrophenol is anthropogenic and dangerous if it contaminates the environment. Therefore, p-nitrophenol needs to be reduced to p-aminophenol which is relatively safer for the environment. In this study, nanoporous silica was synthesized using copolymer triblock PEO100PPO64PEO100 (Pluronic F-127) and PEO20PPO70PEO20 (Pluronic P-123) as template and TEOS (tetraethyl orthosilicate) as silica sources. Transmission Electron Microscope (TEM) characterization of Au nanoparticle/nanoporous silica hybrid materials showed that the formation of pore structures in the nanoporous material and the distribution of Au nanoparticles on nanoporous silica without any agglomeration have been successful. The average pore diameter appears to decrease with increasing use of Pluronic P-123 during synthesis. The activity of Au-SN10 catalyst through the reduction of p-nitrophenol resulted the highest observed rate constant of 0.3685 min?1 indicating that this variant catalyst had the best catalytic activity. N2 adsorption- desorption of Au-SN10 catalyst resulted pore diameter, surface area, and pore volume of 328 m²/g, 0.77 cm³/g, and 10.8 nm, respectively. Through the Arrhenius and Eyring equations on the results of catalytic activity with temperature variations, the kinetic parameters EObs (27.92 kJ/mol), ?H‡ (27.03 kJ/mol), ?S‡ (?184 J/mol.K), and ?G‡ (81.9 kJ/mol). Pursuant to the kinetic studies, synthesized nanoporous silica could be used as a support material for Au catalysts. Determination of the reaction mechanism using the Arrhenius equation at various concentrations of p-nitrophenol and NaBH4 showed that the reaction followed the Langmuir- Hinshelwood reaction mechanism.