Equilibrium, kinetic and thermodynamic studies on the removal of U(VI) by low cost agricultural waste

Kausar, A., Bhatti, H.N. and MacKinnon, G. (2013) Equilibrium, kinetic and thermodynamic studies on the removal of U(VI) by low cost agricultural waste. Colloids and Surfaces B: Biointerfaces, 111, pp. 124-133. (doi: 10.1016/j.colsurfb.2013.05.028)

Abstract

In this research, biosorption efficiency of different agro-wastes were evaluated with rice husk showing maximum biosorption capacity among the selected biosorbents. Optimization of native, SDS-treated and immobilized rice husk adsorption parameters including pH, biosorbent amount, contact time, initial U(VI) concentration and temperature for maximum U(VI) removal was investigated. Maximum biosorption capacity for native (29.56 mg g-1) and immobilized biomass (17.59 mg g-1) was observed at pH 4 while SDS-treated biomass showed maximum removal (28.08 mg g-1) at pH 5. The Langmuir sorption isotherm model correlated best with the U(IV) biosorption equilibrium data for the 10-100 mg L-1 concentration range. The kinetics of the reaction followed pseudo-second order kinetic model. Thermodynamic parameters like free energy (ΔG°) and enthalpy (ΔH°) confirmed the spontaneous and exothermic nature of the process. Experiments to determine the regeneration capacity of the selected biosorbents and the effect of competing metal ions on biosorption capacity were also conducted. The biomass was characterised using scanning electron microscopy, surface area analysis, Fourier transformed infra-red spectroscopy and thermal gravimetric analysis. The study proved that rice husk has potential to treat uranium in wastewater.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: MacKinnon, Dr Gillian
• Authors: Kausar, A., Bhatti, H.N., and MacKinnon, G.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Colloids and Surfaces B: Biointerfaces
• ISSN: 0927-7765
• ISSN (Online): 1873-4367
• Copyright Holders: Copyright © 2013 Elsevier B.V.
• First Published: First published in Colloids and Surfaces B: Biointerfaces 111:124-133
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher