Biosorption of Ni(II) ions from aqueous solutions using Melia azedarach biomass

Abstract

ABSTRACT. Biosorption is a cost effective tool for removing heavy metals from aqueous solutions. In the present study, M. azedarach biomass has been used for the biosorption of Ni(II) ion from aqueous solution. The effect of pH, contact time, concentration and temperature were separately studied. The optimum pH was found to be 6.0. 92% biosorption of Ni(II) ion was founded, when 25 mg/L of initial Ni(II) ion concentrations was used at room temperatures in 60 min. It was also observed that percent biosorption of Ni(II) increases with increase in temperature. The equilibrium biosorption data were analyzed by the Langmuir and Freundlich isotherms both were best fitted to our data. The maximum biosorption capacity (qmax) of 9.345 mg/g for Ni(II) according to Langmuir model. The kinetics of Ni(II) ion revealed that present biosorption process proceeds according to pseudo second order kinetics. From Thermodynamic parameters including Gibbs free energy change (∆G), enthalpy change (DH) and entropy change (ΔS), it was concluded that biosorption of Ni(II) ion using M. azedarach biomass is feasible, spontaneous and endothermic in nature.   KEY WORDS: Ni(II) ions, Melia azedarach, Biosorption, Kinetics, Thermodynamics   Bull. Chem. Soc. Ethiop. 2022, 36(3), 521-530.                                                             DOI: https://dx.doi.org/10.4314/bcse.v36i3.3