Sustainable wastewater treatment: LDH@Fe3O4-Ag as a promising photocatalyst for tetracycline degradation

This study deals with the removal of pharmaceutical contaminants from wastewater, especially tetracycline (TC). For this purpose, calcium/aluminum-based nanolayered double hydroxide (LDH) was synthesized through the co-precipitation method. Subsequently, the pre-synthesized LDH was engineered with Fe3O4 and silver (Ag) nanoparticles to enhance the photocatalytic prowess and ease of use. The resulting LDH@Fe3O4-Ag composites were thoroughly characterized using various analytical techniques, including BET, FESEM, TEM, TGA, FT-IR, XRD, and DRS. The prepared LDH@Fe3O4-Ag composites were then employed as a photocatalyst for TC removal from water. Several critical parameters were methodically optimized, including reaction time, initial TC and LDH@Fe3O4-Ag concentrations, pH, and Ag loading amount. Under optimal conditions (90 min reaction time, pH 9, initial TC concentration of 35 ppm, and LDH@Fe3O4-Ag concentration of 0.05 g/L), an impressive TC removal efficiency of 96.4 % was achieved. Furthermore, the reusability of the photocatalyst, reaction kinetics, and the primary degradation site were investigated. This research presents LDH@Fe3O4-5Ag as a promising solution to address water contamination issues arising from pharmaceutical compounds.