Research Article Open Access

Application of ZnO Nano Rods for the Batch Adsorption of Cr(VI): A Study of Kinetics and Isotherms

Sushma Kamath1, Venu Gopal Vishwakarma Ramanjaneyalu1 and Susmita Kamila1
  • 1 Department of Chemistry, East Point College of Engineering and Technology, Bangalore – 560 049, India

Abstract

The present study reports the synthesis of nano Zinc Oxide (ZnO) and its adsorption behaviour. The ZnO obtained by precipitation method were found to be well-defined nano rods arranged like flower. The shape, size and structure of ZnO were characterized from X-Ray Diffraction (XRD), Energy Dispersive X-ray (EDX) and Scanning Electron Microscope (SEM) analysis. These nano rods were utilized for the adsorption of hexavalent chromium ions [Cr(VI)] from their aqueous solution by using batch adsorption technique. Different physico-chemical parameters such as metal ion concentration, pH, dosage level and equilibrium contact time were studied during adsorption. The amount of chromium adsorption increases with increase in adsorbent dosage, whereas the adsorption was maximum in the first 40 min with optimum value of pH 3. The kinetic of adsorption was best fitted by the pseudo-second-order rate equation. Similarly, the equilibrium adsorption data were fitted well by both Temkin and Freundlich adsorption isotherm models in comparison to Langmuir adsorption model. The adsorption of chromium was supported by EDX and SEM analysis. Moreover, the change in the SEM morphology of ZnO nano rods into nano sheets after adsorption is an interesting observation of the present investigation.

American Journal of Applied Sciences
Volume 16 No. 3, 2019, 101-112

DOI: https://doi.org/10.3844/ajassp.2019.101.112

Submitted On: 22 December 2018 Published On: 12 April 2019

How to Cite: Kamath, S., Ramanjaneyalu, V. G. V. & Kamila, S. (2019). Application of ZnO Nano Rods for the Batch Adsorption of Cr(VI): A Study of Kinetics and Isotherms. American Journal of Applied Sciences, 16(3), 101-112. https://doi.org/10.3844/ajassp.2019.101.112

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Keywords

  • Nano Rods
  • Nano Sheets
  • Adsorbent
  • Hexavalent Chromium Ions
  • Adsorption Isotherm
  • Pseudo-Second-Order Kinetics