Kinetics of scandium ion sorption onto oxidized carbon nanotubes

The present study investigates the sorption behavior of oxidized multiwalled carbon nanotubes (CNTs–COOH) for the sepa-ration and removal of scandium ions from aqueous solutions. The results indicated that CNTs–COOH showed an excellent scandium adsorption capacity of 40.1 mg g−1 (at pH 3) with an uptake time less than 2 min. The pseudo-second-order kinetic model and the film diffusion are the main controlling factors.