Growth of carbon nanotube on micro-sized Al2O3 particle and its application to adsorption of metal ions

Carbon nanotubes (CNTs) were grown on micron-sized Al2O3 particles in an atmosphere of methane and hydrogen at 700 degrees C under the catalysis of Fe-Ni nanoparticles that had been deposited on the surface of Al2O3 particles by an electroless plating technique. The individual and competitive adsorption capacities of Pb2+, Cu2+, and Cd2+ from aqueous solution by CNTs on Al2O3 particles were studied. The results showed that the adsorption behavior of these metal ions by as-grown CNTs on Al2O3 particles is in good agreement with the Langmuir adsorption model. The maximum individual adsorption capacities of Pb2+, Cu2+ and Cd2+ from water by as-grown CNTs on Al2O3 particles are 62.50, 27.03, and 9.30 mg/g, respectively. The CNTs on Al2O3 particles have promising potential applications in removing soluble heavy metals from aqueous solutions.