Magnetic Multi-walled Carbon Nanotube as Effective Adsorbent for Ciprofloxacin (CIP) Removal from Aqueous Solutions: Isotherm and Kinetics Studies

Abstract

Abstract Nowadays, the presence of antibiotics in the environment has been identified as an important concern for the various life cycle. Thus, this study was conducted to evaluate ciprofloxacin (CIP) adsorption efficiency onto the multi-walled carbon nanotube (MWCNTs) and magnetic multi-walled carbon nanotube (MMWCNTs). In this experimental study, the characteristics of the studied adsorbents were determined using SEM, FTIR and XRD methods. The effects of operational parameters including contact time (10–120 min), initial concentration of CIP (10–100 mg/L), adsorbent dosage (0.1–1 g/L) and pH (3–9) were evaluated. The isotherm and kinetics studies of the CIP adsorption onto the studied adsorbents were also carried out. The adsorption efficiency increases by increasing the contact time and adsorbent dosage, while it increased by increasing the CIP initial concentration. The results showed that higher CIP adsorption efficiency was observed at pH = 7, adsorbent dosage of 0.5 g/L, CIP concentration of 30 mg/L and contact time of 120 min. The isotherm and kinetics studies revealed that the CIP adsorption data were better described by the Langmuir isotherm model and pseudo-second-order kinetics equation model. It can be concluded that both of these adsorbents have suitable potential to remove the CIP from aqueous solution but this ability is greater in MMWCNTs.