Removal of atenolol from aqueous solutions by multiwalled carbon nanotubes: isotherm study

Nowadays, ensuring the protection and health of the environment is an effective step toward sustainable development. One of the primary environmental concerns around the world is the removal of pharmaceutical contaminants from water and wastewater. Solving such problem and many other environmental issues, along with treading the path toward sustainable development, can be achieved with the use of nanotechnology. This study investigated the use of multiwalled carbon nanotubes (MWCNTs) in removing the beta-blocker atenolol from aqueous solutions. To achieve this goal, the efficiency of atenolol removal was evaluated in a four-level Taguchi experiment that involved the evaluation of pH value (2-11), contact time (5-90 min), adsorbent dose (0.5-2 g/L), and initial atenolol concentration (10-90 mg/L). Data analysis and interpretation were performed using Design Expert 6. The results indicated that the highest atenolol removal (94.8%) occurred at a pH of 7, a contact time of 20 min, an atenolol concentration of 10 mg/L, and a MWCNT dose of 0.5 g/L. The adsorption capacity of the MWCNTs used in this work was 16.76 mg/g. The data analysis based on the adsorption isotherm models of the Isotherm Fitting Tool showed good agreement with the results of a linear model. The findings confirmed that MWCNTs present great potential as effective adsorbents for the removal of atenolol from water and wastewater.