Fabrication of nanocomposites mediated from aluminium nanoparticles/Moringa oleifera gum activated carbon for effective photocatalytic removal of nitrate and phosphate in aqueous solution

Abstract

The removal of nitrate and phosphate in polluted water is a challenging environmental problem. This study was designed to use a different light spectrum to enhance carbon-based metal nanocomposites adsorbent for the augmented removal of nitrate and phosphate from aqueous solution. Synthesis of aluminium oxide nanoparticle (Al2O3NPs)/Moringa oleifera gum activated carbon (MOGAC) based nanocomposites was conducted using sol-gel method. Incidentally, prepared nanocomposite was subject to evaluate the photocatalytic removal of nitrate and phosphate under different LED light irradiations. The microscopic image of MOGAC showed the pores on its surface, which resembles a honeycomb-like structure. The bandgap energy values of the Al2O3 and Al2O3/MOGAC were 3.16 and 3.22 eV, which corresponded to the reflectance edge of 420 nm. The surface area of Al2O3/MOGAC nanocomposites resolute was recorded as 176.92 m2/g−1. Photocatalytic activity against nitrate and phosphate was carried out by the synthesized nanocomposites under the different LED light spectrum. The red LED light spectrum and 10 mg/L of nanocomposite removed nitrate and phosphate ions up to 94% and 95% after 105 min and 75 min of irradiation, respectively. Overall, the Al2O3/MOGAC nanocomposites maintained good stability after four cycles of nitrate and phosphate reduction.