Magnetic Nanoparticles Decorated with Synthetic Zeolite Derived from Coal Fly Ash: Application to Removal of Heavy Metals and Organic Dyes

Fly ash, a by-product of coal combustion, poses environmental health risks but also has potential for pollutant removal due to its adsorption properties. Enhancing its adsorption capacity through physical or chemical methods can convert this industrial waste into a valuable material. By transforming fly ash into zeolites and modifying it with amino-propyl-imidazole, an ionic liquid, it becomes a template for Fe3O4 nanoparticles (NPs). This leads to the creation of a magnetic film (Fe3O4 NPs@zeolite film), incorporating polymers such as polystyrene sulphonate (PSS), polyvinyl alcohol (PVA), and chitosan. This film is highly effective in adsorbing contaminants like chromium, selenium, and organic dyes (Congo red, RhB), binding them electrostatically through functional groups including imidazolium cationic moiety (R-N+), amino groups from chitosan, and hydroxyl groups (Fe-OH). Efficient across a wide pH range, this film demonstrates great potential for practical applications in environmental remediation, particularly in adsorbing various toxic species in a highly effective manner.