Synthesis of silicalite-1 zeolite using silica from elephant grass (Pennisetum purpureum)

Abstract

Silicalite-1 is a type of zeolite with no aluminum content and is hydrophobic. This zeolite can be synthesized from various types of silica. Elephant grass (Pennisetum purpureum) is one of the potential agricultural wastes that has a fairly high silica content that can be used for zeolite synthesis. In this study, silicalite-1 zeolite was synthesized using silica extracted from elephant grass and tetrapropylammonium bromide (TPABr) templates. Silica samples extracted from elephant grass have 71.91% amorphous SiO2 content. Silicalite-1 zeolite was synthesized with molar ratio of 1SiO2 : 0.527TPABr : 0.395Na2O : 98.45 H2O, using hyrothermal method at 180°C for 24 hours in a stainless steel-teflon lined autoclave. The resulting silicalite-1 samples were confirmed by X-Ray Diffraction (XRD) and showed 2θ which was typical for silicalite-1 i.e. 8.02°, 8.93°, 23.09°, and 23.98°. The results of Scanning Electron Microscopy (SEM) show that silicalite-1 zeolite has hexagonal crystals with 43.36 μm size as a result of the calculation using the Schrerrer method.