Adsorption of uranium on natural and thermally activated zeolitic tuff: kinetic, thermodynamic and isotherm studies Online publication date: Sat, 06-Jul-2019
by Kamel K. Al-Zboon; Mohammad S. Al-Harahsheh
International Journal of Environment and Waste Management (IJEWM), Vol. 24, No. 1, 2019
Abstract: The adsorption capacity of natural and thermally activated ZT for uranium was investigated under different conditions. The obtained results indicated that the Jordanian ZT has obtained high removal efficiency up to 99% at low U concentration (10 mg/L) and a maximum uptake capacity of 14.22 mg/g at an optimum pH of 5. About 78% removal can be achieved within the first 10 min of contact time. Thermal activation of ZT at temperatures of 100-250°C decreased the removal efficiency and then increased at a temperature of 300°C. Kinetic study indicated high impact of temperature on the adsorption rate with best fitting with the pseudo second order model. Langmuir isotherm model provided better simulation of the experimental data than Freundlich and R-P models, indicating monolayer, homogenous and spontaneous process. Positive ΔHo (56-87 kJ/mole), positive S* (0.25 to 0.36 kJ/mole.K), and negative ΔG° (-18.85 to -27.77 kJ/mole) indicated endothermic, high adsorption affinity and physiochemical process.
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Environment and Waste Management (IJEWM):
Login with your Inderscience username and password:
Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.
If you still need assistance, please email subs@inderscience.com
Our Blog 
Follow us on Twitter 
Visit us on Facebook