Oxidation of carbon nanotubes using for Cu(II) adsorption from aqueous solution

Carbon nanotubes (CNTs) synthesized by chemical vapour deposition without using hydrogen were oxidized with 0.1 M potassium permanganate at 40oC for 2 hours and exhibited high CuII adsorption capacity from aqueous solution. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscope (SEM), transmission electron microscope (TEM) and nitrogen adsorption/desorption isotherms were used to characterize the oxidized CNTs. After oxidizing, the obtained CNTs were used to remove CuII from aqueous solution. With CuII initial concentration of 20 mg.L-1, at pH of 4 and adsorbent dosage of 0.2 g.L-1, the oxidized CNTs exhibited high CuII adsorption ability with maximum adsorption capacity of 174.4 mg.g-1.