Removal of hexavalent chromium from aqueous solution using activated carbon derived from palmyra palm fruit seed

Abstract

 In this study, removal of chromium(VI) from aqueous solutions by Palmyra palm fruit seed carbon (PPFSC) and commercial activated carbon (CAC) was investigated. The metal adsorption capacity has been studied as a function of contact time, pH and carbon dosage. The adsorption yields increased with the increasing of adsorbent dosage and contact time, and subsequently reached the equilibrium. The suitability of the Freundlich and Langmuir models were also investigated for each chromium sorbent system. In order to understand the reaction mechanism, kinetic data has been studied using pseudo first order rate equation. The Lagergren’s constants were calculated for different initial concentrations of metal ions. The chromium(VI) ions could be rapidly removed from the sorbents by treatment with HCl acid and at the same time the regenerated sorbent could be used again to adsorb heavy metal ions. The suitability of this material for treatment of tannery wastewater was also examined.

KEY WORDS: Adsorption; Chromium(VI) removal; Palmyra palm fruit seed carbon; Regeneration; Langmuir and Freundlich isotherm; Pseudo first order kinetics

Bull. Chem. Soc. Ethiop. 2008, 22(2), 183-196.