Abstract

Batch Studies for the Adsorption of Lead (II) from Aqueous Phase by Waste Generated from Citrus Limettioides

Author(s): R. Sudha, K. Srinivasan and P. Premkumar

The Pb (II) adsorption behaviour of carbon derived from citrus Limettioides seed, which is a novel waste material (CLSC), was investigated as a function of parameters such as agitation time, solution pH and temperature. The maximum uptake of lead (II) ion was obtained at pH 4.0-6.0. Adsorption equilibrium was established by 4 hr. The functionality of the CLSC was characterized by FT-IR spectra. The Freundlich, Langmuir, Temkin, Dubinin-Radushkevich, Redlich-Peterson and Sips models were applied to describe the equilibrium isotherms using nonlinear regression analysis. The equilibrium data fits well for the Langmuir, Redlich-Peterson and Sips adsorption isotherms. The Langmuir monolayer adsorption capacity of CLSC was found to be 142.86 mg/g. Thermodynamic parameters such as ∆Go , ∆Ho and ∆So have also been evaluated and it has been found that the sorption process was feasible, spontaneous and exothermic in nature. Results indicate that CLSC can be used as an effective and environmentally friendly adsorbent to detoxify Pb (II)-polluted wastewaters.