Binding of nickel and zinc ions with activated carbon prepared from sugar cane fibre (saccharum officinarum L.)

Abstract

Activated carbon was prepared from sugar cane fibre by carbonizing at 500 ^oC for 30 minutes. This was followed by activation with ammonium chloride. The activated carbon was characterised in terms of pH, bulk density, ash content, surface area and surface charge. Equilibrium sorption of nickel and zinc ions by the activated carbon was studied using a range of metal ion concentrations. The sorption data was observed to have an adequate fit for the Langmuir isotherm equation. The level of metal ion uptake was found to be of the order: Ni²⁺ > Zn²⁺. The difference in the removal efficiency could be explained in terms of the hydration energy of the metal ions. The distribution coefficient for a range of concentration of the metal ions at the sorbent water interface is found to be higher than the concentration in the continuous phase.

KEY WORDS: Nickel, Zinc, Activated carbon, Sugar cane fibre, Langmuir isotherm

Bull. Chem. Soc. Ethiop. 2007, 21(1), 151-156.