Kinetic and equilibrium study for the sorption of Pb(II) ions from aqueous phase by water hyacinth (Eichhornia crassipes)

Abstract

This paper reports the kinetic and equilibrium studies of Eichhornia crassipes root biomass as a biosorbent for Pb(II) ions from aqueous system. Batch adsorption studies were carried out to examine the influence of various parameters such as the pH, contact time, adsorbent dose, initial metal ion concentration, temperature and agitation speed on the metal ion uptake. Uptake of Pb(II) ions on the E. crassipes roots showed a pH-dependent profile. The maximum metal uptake values were 164 μg/mL. Langmuir model fitted the experimental sorption equilibrium data with a good fit (R² > 0.99). The biosorption kinetics was described by the pseudo-second-order model (R² > 0.99).

KEY WORDS: Water hyacinth, Biosorption, Kinetics, Water treatment, Pb(II) removal

Bull. Chem. Soc. Ethiop. 2012, 26(2), 181-193.

DOI: http://dx.doi.org/10.4314/bcse.v26i2.3