Efficient Multi-walled Carbon Nanotubes/Iron Oxide Nanocomposite for the Removal of the Drug Ketoprofen for Wastewater Treatment Applicationes

摘要

Current environmental restrictions, such as the zero liquid discharge policy, require developing new methods to completely remove micropollutants from wastewater. Non-steroidal anti-inflammatory drugs (NSAID) are major component of such pollutants. The adsorptive removal of ketoprofen (KP), a widely prescribed NSAID, was studied using a newly synthesized magnetic adsorbent. The maximum adsorption capacity was determined to be 39.2 mg/g with almost 98% removal for 50 mg/L KP at neutral pH. The adsorption of KP was found to be pH dependent and more efficient in acidic media. The isothermal behavior of the adsorbent followed a sigmoidal behavior and was best fitted to the corresponding-states equation (CSE). The adsorption was found to follow second-order kinetics with a half-life of 4.4 min. The adsorption was also found to be exothermic and therefore it is favorable at low temperatures. The study also showed that the adsorbent can be regenerated for several adsorption-desorption cycles. The adsorption mechanism was also explored by state-of-the-art periodic quantum theoretical calculationes.