Adsorption isotherm studies of Cd (II), Pb (II) and Zn (II) ions bioremediation from aqueous solution using unmodified and EDTA-modified maize cob

AUTOR(ES)

Igwe, J.C, Abia, A.A.

FONTE

Eclética Química

DATA DE PUBLICAÇÃO

2007

RESUMO

The need to clean-up heavy metal contaminated environment can not be over emphasized. This paper describes the adsorption isotherm studies of Cd (II), Pb (II) and Zn (II) ions from aqueous solution using unmodified and EDTA-modified maize cob. Maize cob was found to be an excellent adsorbent for the removal of these metal ions. The amount of metal ions adsorbed increased as the initial concentration increased. Also, EDTA - modification enhanced the adsorption capacity of maize cob probably due to the chelating ability of EDTA. Among the three adsorption isotherm tested, Dubinin-Radushkevich gave the best fit with R² value ranging from 0.9539 to 0.9973 and an average value of 0.9819. This is followed by Freundlich isotherm (Ave. 0.9783) and then the Langmuir isotherm (Ave. 0.7637). The sorption process was found to be a physiosorption process as seen from the apparent energy of adsorption which ranged from 2.05KJ\mol to 4.56KJ\mol. Therefore, this study demonstrates that maize cob which is an environmental pollutant could be used to adsorb heavy metals and achieve cleanliness thereby abating environmental nuisance caused by the maize cob.

Documentos Relacionados

• ADSORÇÃO DE Pb (II), Cd (II) E Cu (II) EM ARGILA CAULINÍTICA NATURAL E ARGILA NATURAL CONTENDO MONTMORILONITA.
• Biosorption kinetics of Cd (II), Cr (III) and Pb (II) in aqueous solutions by olive stone
• Sorption kinetics and intrapaticulate diffusivity of As(III) bioremediation from aqueous solution, using modified and unmodified coconut fiber
• Estudo do potencial de biossorÃÃo dos Ãons Cd (II), Cu (II) e Zn (II) pela macrÃfita Eichhornia crassipes
• AvaliaÃÃo do potencial de biossorÃÃo dos Ãons Cd (II), Cu (II) e Zn (II) pela macrÃfita Egeria densa