Kinetics of copper ions sorption onto activated carbon, carbon nanotubes and carbon-encapsulated magnetic nanoparticles

The paper deals with comparative kinetics studies of copper ion sorption onto three different carbon sorbents: activated carbon, carbon nanotubes and carbon-encapsulated magnetic nanoparticles. The studied sorbents possess many structural and morphological differences, which include the primary particle size, grain size, graphitization degree, surface area and density of surface acidic groups. The kinetics studies were performed at base and acidic pHs and involved various starting concentrations. It has been found that nanostructured carbon sorbents adsorb the Cu(II) ions faster than activated carbon. The density of surface functional groups was found to be a parameter that primarily drives the sorption rates.