Background and purpose: Removal of emerging pollutants from water and wastewater is a great concern in environmental issues. In this study the Taguchi method as one of the major methods for experimental designs was used to assess the removal of atenolol from aqueous solution by multi-wall carbon nanotubes.

Materials and methods: In an experimental study in a batch system to investigate the factors affecting atenolol absorption (pH, contact time, absorbent dose, and initial concentration of atenolol) Taguchi design was used in four levels with L-16 matrix. The properties of the absorbent were determined using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The absorption isotherm models were analyzed by Design Expert 6.

Results: The optimum conditions for pH, contact time, MWCNT dose and initial concentration of atenolol to affect the absorption on multi-walled carbon nanotubes were 7, 20 minutes, (0.5 gr/l), and (10 mg/l), respectively. The removal efficiency and absorption capacity in optimum condition were 94.8% and 16.76 mg g^-1, respectively. The data was evaluated by absorption models such as Langmuir, Freundlich and Dubinin Radeshkevich. The equilibrium data was well fitted with Freundlich model (R²=0.93).

Conclusion: This study showed that multi-walled carbon nanotubes as an effective absorbent have a high potential to remove atenolol from water and wastewater.