Synthesis and Characterization of Silver-Polyacrylonitrile-Zeolite Nanocomposite for Drinking Water Treatment

Abstract

Water pollution poses a significant threat to public health and the environment, necessitating the development of effective water treatment technologies to ensure access to safe and clean drinking water. The focus of this thesis was on the synthesis and characterization of silver-polyacrylonitrile-natural zeolite (Ag-PAN-NZ) nanocomposite designed for the removal of iron, manganese, and lead from drinking water, along with E. coli disinfection. The nanocomposite was synthesized by combining milled natural zeolite with PAN powder using the solvent casting technique, with the concurrent incorporation of silver nanoparticles. Optimization through Central Composite Design revealed the optimum synthesis conditions as an 80% zeolite composition, a reaction temperature of 38°C, and a reaction time of 135 minutes, resulting in a nanocomposite with a Methylene Blue Number of 14.4 mg g⁻¹ and a Minimum Inhibitory Concentration value of 626.667 μg mL⁻¹. Characterization techniques, including scanning electron microscopy, X-ray fluorescence, Fourier-transform infrared spectroscopy, and methylene blue adsorption, revealed a porous structure primarily composed of silicon dioxide (SiO2) at 66.54% and aluminium oxide (Al2O3) at 21.77%, with a specific surface area of 14.06 m² g⁻¹ and an average particle diameter of 1.78 mm. The nanocomposite exhibited impressive adsorption capacities for iron, manganese, and lead at 96%, 98%, and 61%, respectively, within six hours. Additionally, it demonstrated efficient E. coli disinfection within 30 minutes and remarkable regeneration efficiency over five adsorption-desorption cycles. This study shows the potential of the synthesized nanocomposite as a sustainable and effective solution for disinfection and metal ion removal from water.