Abstract :
The adsorption nature of bio-adsorbents obtained from Pongamia pinnata plant in the extraction of Al (III)
ions from waste waters is studied by varying different parameters and by using Batch systems of extraction
procedures. Various parameters have been optimized for the quantitative removal of Al (III) to an extent of 100%.
Adsorption isotherms are analyzed and the obtained correlation coefficient (R2
) and dimensionless separation factor
(RL) values confirm that adsorption obeys Langmuir adsorption indicating monolayer formation. Further, the
‘physisorption’ nature of the sorption process is confirmed by Temkin as well as Dubinin-Radushkevich isotherms.
On analysis of adsorption kinetics by various models, it is observed that pseudo second order model is better
explaining the sorption process. The thermodynamic study reveals the endothermic nature for adsorption process.
Common cations and some anions even in tenfold excess have shown marginal interference but Cland
Feffected
and while PO4
3-
synergistically maintained the 100% removal. The developed procedure is successful when applied
to samples of waste waters from industries and contaminated lake waters.
Keyword :
Aluminum (III), pollution control, bio-sorbents, Pongamia pinnata, adsorption isotherms and kinetics, applications