Characterization of Metal-Impregnated Charcoal: Nitrogen Adsorption

Nitrogen adsorption on metal (Ni, Cu, Zn) impregnated charcoal has been carried out at 77 K by the continuous flow method using a Quantasorb sorption system. It was observed that such metal impregnation did not contribute any extra surface area to the charcoal. The values of the surface area, micropore and total pore volumes determined from nitrogen adsorption follow the sequence Ni–charcoal < Cu–charcoal < Zn–charcoal < charcoal. Their behaviour is discussed in terms of the ionic radii of the metal ions concerned. The pore size distribution curves demonstrate the microporous nature of the charcoal, with the micropores contributing significantly to the total pore volume.