Among pharmaceuticals,antibiotics are the most widely used drug for the prevention or treatment of bacterial infections in humans,animals and plants. Amoxicillin is a broad-spectrum b-lactam antibiotic that belongs to penicillin class organism used as veterinary medicine for treatment of bacterial infections encountered in gastro-intestinal and systemic infections. Amoxicillinhas also been known to be hardly degradable, remains as active compound within urine and feces. In addition, amoxicillin accumulates through industrial route, where the concentration is usually higher than that originated from public excretion which may associate some problems in the future. Effluent containing antibiotics needs to be treated chemically or physically to prevent the adverse effects from contaminated water.Physical techniques are the most appropriate treatment options. Among various physical methods, adsorption is the most efficient route for removing organic compounds from industrial effluent. In this method, the properties of the adsorbents are very effective on the adsorption rate. In the recent two decades, carbon nanotubeshave been startlingly in the centre of the scientists’attention due to their unique physical and chemical properties. In this study,multi-walled carbon nanotubes (MWCNTs) are examined to separate amoxicillin from aqueous environment. To enhance the adsorption rate of CNTs, their surfaces were modified with 8-hydroxyquinoline molecule. FTIR and SEM analyses showed the successful modification of the MWCNTs surface with 8-hydroxyquinoline. After that, both pristine and functionalised MWCNTs were applied to remove the amoxicillin from aqueous samples. Adsorption results show that the modification of MWCNTs with 8-hydroxyquinoline significantly enhances the removal efficiency of amoxicillin about 12 %. Moreover, investigating the kinetic rate of adsorption confirms a fast kinetic rate of amoxicillin adsorption on the functionalized CNT in comparison to pristine CNT. Kinetic behaviour of both pristine and functionalised CNT obeys pseudo second order model that shows a rapid kinetic rate of separation. At last, the effect of pH was investigated on the adsorption amount of antibiotic. Results showed that the maximum adsorption amount of amoxicillin occurs on PH=6.5 of the solution.

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