Preparation and properties of novel activated carbon doped with aluminum oxide and silver for water treatment

Abstract

Novel activated carbon (AC) composite materials, namely AC doped with aluminum oxide (Al2O3) and AC doped with Al2O3 and silver (Ag) nanoparticles, have been prepared via a one-step thermal decomposition method. The developed composite materials were used to study the adsorptive removal of molybdenum (Mo) and arsenic (As) from contaminated water. Several techniques, including X-Ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron spectroscopy (SEM), energy dispersive X-Ray spectroscopy (EDS), and thermal gravimetric analysis (TGA), were used to characterize the synthesized materials. TGA results show that the material is very stable and decay starts only above 450 °C. The effects of pH on the adsorptive removal of As and Mo on AC-Al2O3 have also been studied. The prepared AC-Al2O3 material showed 94% removal of total As at pH of 6% and 97% removal of Mo at pH 2. The pollutants removal is due to electrostatic attraction and ligand exchange adsorption mechanisms. It was also found that the novel AC-Al2O3-Ag composite materials exhibit notable antibacterial properties towards both Gram-negative (Escherichia coli) and Gram-positive (Bacillus subtilis) bacteria.