Abstract
Activated carbon was prepared from peanut shell by chemical activation with KOH. Unoxidized activated carbon was prepared in nitrogen atmosphere which was then heated in air at a desired temperature to get oxidized activated carbon. The prepared carbons were characterized for surface area and pore volume and utilized for the removal of Cr(VI) from aqueous solution. The effects of pH, contact time, initial concentration of adsorbate and temperature on adsorption of Cr(VI) were investigated. Adsorption kinetics of Cr(VI) was analyzed by pseudo first order, pseudo second order and intraparticle diffusion kinetic models. Results showed that Cr(VI) adsorption on both oxidized and unoxidized samples followed the first and second order kinetics models most appropriately. Isotherm data were treated according to Langmuir and Freundlich models. The results showed that both Langmuir and Freundlich models fitted the data reasonably but the Langmuir adsorption isotherm model fitted better in the temperature range studied. The adsorption capacity was found to increase with temperature, showed endothermic nature of Cr(VI) adsorption. The thermodynamic parameters, such as Gibb's free energy change (ΔG°), standard enthalpy change (ΔH°), standard entropy change (ΔS°) were evaluated. The value of ΔG° was found negative for the adsorption of Cr(VI) which confirmed the feasibility and spontaneity of the adsorption process.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
