BATCH ADSORPTION OF OFLOXACIN ONTO ACTIVATED CARBON DERIVED FROM EGGSHELLS

The aim of this study is to investigate the potential of eggshells as a precursor for activated carbon in the removal of ofloxacin from aqueous media. The dried eggshells were ground, and particle size separation was used to retain particles with diameters between 1 and 2 mm. This ground material was activated with 30% orthophosphoric acid at a ratio of 0.5 and then calcined at 600 C in an oven for 1 hour. Characterisation tests were carried out to determine the iodine index, specific surface area, surface functions, and pHzpc. During the adsorption tests, the residual concentrations of ofloxacin were monitored using a high-performance liquid chromatograph (HPLC). The contact time, mass of activated carbon, pH, and initial concentration of the pollutant were varied for the removal of ofloxacin. The adsorption kinetics were modelled. The results reveal that the prepared activated carbon has an iodine index of 450.85 mg/g and a specific surface area of 5.29 m2/g, and is predominantly mesoporous. It is basic in nature, with a pHpzc value of 7.4. The adsorption of ofloxacin is optimal (65.75%) at a pH of 6, a carbon mass of 8 g, an initial concentration of 20 mg/L, and a contact time of 90 minutes. The pseudo-second-order model and the Langmuir and Dubinin-Radushkevich isotherm models are suitable for describing the adsorption process.