Studies on the Removal of Amoxicillin by Single Walled Carbon Nanotubes
Davoud Balarak
Department of Environmental Health, Health Promotion Research Center, School of Public Health, Zahedan University of Medical Sciences, Zahedan, Iran.
Yousef Mahdavi
Department of Environmental Health Engineering, Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran.
Afshin Maleki
Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Hiua Daraei
Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Shahram Sadeghi *
Department of Environmental Health Engineering, Student Research Committee, Kurdistan University of Medical Sciences, Sanandaj, Iran.
*Author to whom correspondence should be addressed.
Abstract
The research was conducted to determine effectiveness of CNTs as sorbents for removal of AMO from aqueous solution and to analyze the impact of various parameters including adsorbent dosage, initial Amoxicillin concentration, contact time and temperature on the adsorption capacity of CNTs. The percentage of AMO removal decreased with increase in initial concentration. Adsorption equilibrium of AMO removal was observed after 45 min of contact time. Maximum AMO removal efficiency was obtained to be 99.1% and best results were achieved in contact time of 45 min, adsorbent dosage of 0.3 g/l, initial AMO concentration of 200 mg/l and temperature equal with 323 K. Equilibrium data were fitted to Langmuir and Freundlich isotherms, and their constants were determined. Using the linear correlation coefficients showed that the Langmuir isotherm best fits the AMO adsorption data on SWCNTs. The experimental data were fitted into the following kinetic models: pseudo-first-order, pseudo-second-order, and the intraparticle diffusion model. It was observed that the pseudo-second-order kinetic model described the adsorption process better than any other kinetic models. All results found concluded that SWCNTs could be effectively employed as an effective new adsorbent for the removal of Antibiotics from aqueous solutions.
Keywords: Adsorption, carbon nanotubes, amoxicillin, isotherm, kinetic model.