Removal of Chromium(VI) from Aqueous Solution by Fly Ash: Thermodynamic and Kinetic Study

Pooja Soni1, Pragya Khandelwal2 and Shweta Saxena*

Research Scholar, Department of Chemistry, 1,2Career Point University, Kota, Rajasthan, Principal*, Maa Bharti P.G. College, Kota, Rajasthan, INDIA.


The objective of this study is to assess the uptake of hexavalent chromium Cr(VI) from aqueous solutions onto Fly ash. The study also investigates the effect of temperature. Thermodynamic parameters such as enthalpy change (ΔH˚), free energy change (ΔG˚) and entropy change (ΔS˚) were calculated. The ΔG˚ and ΔH˚ values for Cr(VI) adsorption on the fly ash showed the process to be spontaneous and endothermic in nature. The adsorption data follow the Langmuir model better than the Freundlich model and the adsorption equilibrium was described well by the Langmuir isotherm model.

Keywords :Adsorption, batch method, point of zero charge, kinetics.