Fabrication of a magnetic graphene oxide-supported hexagonal cobalt MOF for fast and effective removal of tetracycline in water.

Antibiotic contamination in aquatic environments represents a major threat to ecosystems and human health, demanding efficient remediation strategies. This work reports the synthesis of a facile and efficient magnetic graphene oxide-supported cobalt metal-organic framework (m-GO/Co-MOF) composite for efficient tetracycline (TET) removal from water. The synthesized composite was comprehensively characterized using techniques such as Transmission Electron Microscopy (TEM), Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX), Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) which confirmed its structure features, morphology, and magnetic properties. Additionally, it demonstrated a high surface area of 714.94 m2 g-1 with an average pore diameter of 1.39 nm, indicating a microporous structure. Batch adsorption studies demonstrated rapid adsorption kinetics and maximum removal efficiency (98%) under optimized conditions (C 0 = 0.2 mg L-1, shaking speed = 250 rpm, adsorbent dose = 0.1 g L-1, pH = 7, T = 25 °C). The adsorption behavior followed a pseudo-second-order kinetic model, indicating chemisorption. The equilibrium data are best described by the Langmuir isotherm model, indicating monolayer adsorption with a maximum adsorption capacity of 185.87 mg g-1 at 45 °C. Moreover, the findings from thermodynamic analysis suggest that the adsorption proceeds spontaneously with an endothermic nature. Additionally, the adsorbent exhibited good stability and reusability with minimal performance loss. These results demonstrate that m-GO/Co-MOF is an efficient, reusable, and promising adsorbent for the disposal of TET from water.