removal of uranium (VI) from aqueous solutions onto activated carbon developed from grinded used tire

• Published in: Environmental science and pollution research international 2014, Vol.21 (1), p.684-694
• Main Authors: Belgacem, Ahmed, Rebiai, Rachid, Hadoun, Hocine, Khemaissia, Sihem, Belmedani, Mohamed
• Format: Article
• Language: English
• Subjects: Activated carbon; Adsorbents; Adsorption; Aquatic Pollution; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Bioremediation; Carbon; Charcoal - chemistry; correlation; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Free energy; Gibbs free energy; Hydrogen-Ion Concentration; ions; Isotherms; Kinetics; Mathematical models; Metal concentrations; Metal ions; Nitrogen; Pore size; Porosity; Raw materials; Research Article; Size distribution; Sorption; Studies; Surface area; Surface chemistry; Temperature; Thermodynamics; Tires; Uranium; Uranium - analysis; Uranium - chemistry; Waste Disposal, Fluid; Waste Water Technology; Water Management; Water Pollutants, Radioactive - analysis; Water Pollutants, Radioactive - chemistry; Water pollution; Water Pollution Control; Water Purification - methods
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-013-1940-2

In this study, activated carbon was prepared from waste tire by KOH chemical activation. The pore properties including the BET surface area, pore volume, pore size distribution, and average pore diameter were characterized. BET surface area of the activated carbon was determined as 558 m²/g. The adsorption of uranium ions from the aqueous solution using this activated carbon has been investigated. Various physico-chemical parameters such as pH, initial metal ion concentration, and adsorbent dosage level and equilibrium contact time were studied by a batch method. The optimum pH for adsorption was found to be 3. The removal efficiency has also been determined for the adsorption system as a function of initial concentration. The experimental results were fitted to Langmuir, Freundlich, and Dubinin–Radushkevich (D-R) isotherm models. A comparison of best-fitting was performed using the coefficient of correlation and the Langmuir isotherm was found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of uranium ions onto waste tire activated carbon was 158.73 mg/g. The thermodynamic equilibrium constant and the Gibbs free energy were determined and results indicated the spontaneous nature of the adsorption process. Kinetics data were best described by pseudo-second-order model.