Fabrication of aluminum-coated glucose/graphene oxide hybrid materials for the dual adsorption of fluoride and methylene blue

Wastewater treatment requires materials with a high capacity for adsorbing diverse pollutants. A novel adsorbent was synthesized herein by wrapping glucose/graphene oxide hybrids with aluminum hydroxide in a cetyltrimethylammonium bromide microemulsion and was used for dual adsorption of fluoride (FL) and methylene blue (MB) from water. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) analysis, and Barrett–Joyner–Halenda analysis were employed to characterize the synthesized adsorbent. The pH, initial pollutant concentration, adsorbent dose, and contact time for dual adsorption were determined. Isotherm and kinetic models were applied to investigate the dual adsorption mechanism. Attributed to the good microstructure, enhanced surface area, and ion-exchange behavior, the maximum adsorption capacity of this adsorbent was 14.8 mg/g for FL (1.0 g/L adsorbent) and 232.6 mg/g for MB (0.2 g/L adsorbent) simultaneously at pH 6.0. The enhanced adsorption efficiency and multi- selectivity of this adsorbent suggest its potential to decrease the regeneration frequency of adsorption materials, lower processing costs, and mitigate environmental impacts. This adsorbent is suitable for future development as a sustainable slow-release agent, enabling prolonged use with straightforward operational procedures and efficiency.