Preparation of a high siliceous ZSM-5 from renewable silica source

In this study, a highly siliceous ZSM-5 zeolite of elemental silicon to aluminum ratio of 365 was synthesized using rice husk ash (RHA) as a renewable source. The RHA was used to produce silica sol which, with the organic template tetrapropyl ammonium bromide as the structure directing agent, went through hydrothermal reaction at low temperature and under atmospheric pressure in alkaline medium to form ZSM-5. The synthesized ZSM-5 was characterized using a variety of analytical techniques, including X-ray diffraction, Fourier transformation infrared spectroscopy, scanning electron microscopy N2 adsorption, and X-ray fluorescence. The specific surface area was measured by the Brunauer, Emmet, and Teller (BET), Langmuir, and density functional theory (DFT) methods. Furthermore, the pore volume and pore sizes were determined using Horvath–Kawazoe, Saito Foley, Dubinin–Radushkevich, and DFT methods and the results of these analyses compared well with the referenced ZSM-5.