Silver Loaded Hydrothermal Synthesized Zeolite from Kaolinite and its Performance in Bacterial Inhibition
Siti Nabihan Ishak and Nik Ahmad Nizam Nik Malek
Department of Biosciences, Faculty Science, Universiti Teknologi Malaysia, 81310, UTM Skudai, Malaysia
Abstract
The aim of this work was to synthesis zeolite from kaolinite as a source of silica and alumina by exploring the effect of different crystallization temperatures at 100˚C, 120˚C, and 140˚C in a hydrothermal condition. This work focused on the phase transformation and morphological changes from kaolinite to zeolite using hydrothermal technique. The characterization of starting material, intermediate, and final product were performed by using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDX). The characterization results showed the transformation of kaolinite to amorphous metakaolin after calcined at 900˚C and in the presence of sodium hydroxide as activating agent; the amorphous metakaolin was successfully reconstructed into synthesized crystal zeolite. Synthesized zeolite type A was produced at 100˚C while sodalite was synthesized at 120˚C and 140˚C. Following this, the synthesized zeolites were modified with silver ion by using ion exchange method. Disc diffusion technique (DDT) revealed that silver ion-exchanged zeolite showed significant antibacterial effect against Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538. It was found that, zeolite can be synthesized using economical raw material and modified with silver ion to enhance its antibacterial activity.
Keywords: Zeolite, Kaolinite, Silver, Escherichia coli and Staphylococcus aureus
Topic: Biochemistry