ABSTRACT
In this present work, Ca-alginate-biochar adsorbent has been synthesized, characterized and tested its effectiveness in the removal of aqueous phase Zn2+ metal. The removal efficiency was studied under various physicochemical process parameters. External mass transfer model, intraparticle diffusion model and pseudo-first-order and pseudo-second-order models were used to fit the experimental Zn2+ adoption kinetic results and to identify the mechanism of adsorption. The desorption studies indicate the possibilities of ion-exchange and physical–chemical adsorption of Zn2+. The adsorption was best described by Langmuir isotherm model. Thermodynamic parameters suggested that the adsorption process becomes spontaneous, endothermic and irreversible in nature.
Graphical Abstract
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Acknowledgments
The authors acknowledge the Department of Chemical Engineering, IIT Kharagpur, India and Curtin University, Australia for providing all research instruments and financial support to carry out this study. The authors are highly thankful to the MMF laboratory of John de Laeter Centre of Curtin University for the SEM imaging and XRD analysis.