Adsorptive Removal of Daunorubicin from Water by Graphene Oxide, Activated Carbon, and Multiwalled Carbon Nanotubes: Equilibrium and Kinetic Studies

The adsorption of anticancer drug daunorubicin from aqueous solution by carbonaceous adsorbents was investigated. The adsorption performances of graphene oxide (GO), activated carbon (AC), and multiwalled carbon nanotubes (MWCNTs) were compared. The effects of solution pH, contact time, and initial daunorubicin concentration on the removal of daunorubicin were explored. Isotherm and kinetic models were applied to predict the efficiency of the adsorbents. The major functional groups of the adsorbents were identified by FTIR spectroscopy. In alkaline medium, adsorption increases with increasing pH value. With increasing initial concentration, adsorption capacity increases and removal efficiency decreases. Kinetic studies showed that the pseudo-second-order model describes adsorption onto GO well, whereas the intraparticle diffusion model gives the best fits for AC and MWCNTs. The adsorption isotherm fits the Langmuir model very well.