DOI: https://doi.org/10.55373/mjchem.v27i5.17

Keywords: Coal bottom ash; mesoporous silica; erythrosine adsorption

Abstract

In recent years, a large amount of coal bottom ash (CBA) has been generated as a by-product of coal-fired power plants and discharged into the environment, subsequently raising global concern and contributing to serious environmental burdens. Converting this thermal waste into more valuable products is highly desirable for global resource conservation and environmental sustainability. Due to its high silica content, CBA can serve as a silica source for synthesising a variety of porous materials. In this study, alkaline fusion was used to extract silica from CBA, and the resulting supernatant solution provided a silica source for synthesising mesoporous silica materials. Extensive characterisation of these materials was conducted using Fourier Transform Infrared (FTIR) Spectroscopy, Powder X-ray Diffraction (PXRD), and Scanning Electron Microscopy with Energy Dispersive X-ray Analysis (SEM-EDX) to identify the functional groups, crystalline phases, and surface morphology. The results indicated the presence of surface hydroxyl groups and symmetric Si-O stretching in the FTIR spectra, confirming the successful synthesis of mesoporous silica. The XRD patterns showed an ordered pore structure, while the EDX spectra identified silica and oxygen elements in the synthesised materials. Additionally, adsorption studies were performed to evaluate the potential of the synthesised mesoporous silica materials as adsorbents for removing erythrosine, a synthetic dye, from aqueous solutions. Preliminary results showed that the silica materials exhibited effective adsorption capacity for erythrosine, demonstrating their potential for environmental applications in dye removal. This approach demonstrates that using a low-cost silica source like CBA offers a promising pathway to transform coal waste into valuable products, potentially contributing to the industrial-scale production of porous materials for environmental cleanup.