Abstract

Jayati Chatterjee¹, Neena Rai² and Santosh K Sar³

DOI : http://dx.doi.org/10.13005/ojc/300251

Antibiotics are emerging contaminants in the aquatic environment because they have adverse effects on the aquatic life and humans. The use of antibiotics in human and veterinary medicine has a significant effect on the quality of surface and groundwater. The relevance of an electrocoagulation (EC) process for the removal of an antibiotic was selected because of its wide application, high solubility in water, high residual toxicity and an absence of biodegradability, was examined in this study. Metal hydroxides generated during EC were used to remove Amoxicillin (AMX) from aqueous solution. The knowledge regarding the removal mechanism of this substance has not yet been investigated till now. Experiments were carried out in a batch electrochemical reactor using aluminum electrodes. The removal of AMX was relatively fast and equilibrium was reached within 20 min. The effects of the main operating parameters were examined and showed that irrespective of the initial concentration and for pH ranging from 3 to 10, maximum removal efficiency remained close to 95%; while a sharp decrease was recorded at pH 2 (8 % removal). The results of this study also showed that the removal of AMX from water was strongly affected by the current intensity. The mechanism of electrocoagulation was modeled using isotherm models and showed that the Sips isotherm matched satisfactorily the experimental data, suggesting monolayer coverage of adsorbed molecules and assumed a quasi-Gaussian distribution energy owing to the high correlation also found for the Toth model. In addition, adsorption kinetic studies showed that the EC process followed a pseudo-second-order kinetic model at the various current densities, as when the pH and initial antibiotic concentrations were considered.

Adsorption; Electrocoagulation; Amoxicillin; Kinetics; Isotherm

[ View HTML Full Text]