Uranium(VI) Removal by Nanoscale Zerovalent Iron in Anoxic Batch Systems

• Published in: Environmental science & technology Vol. 44; no. 20; pp. 7783 - 7789
• Main Authors: Yan, Sen, Hua, Bin, Bao, Zhengyu, Yang, John, Liu, Chongxuan, Deng, Baolin
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.10.2010
• Subjects: Applied sciences; Calcium; Environmental Processes; Environmental science; Exact sciences and technology; Iron; Iron - chemistry; Kinetics; Metal Nanoparticles; Oxidation-Reduction; Oxygen - chemistry; Pollution; Spectrum analysis; Studies; Uranium; Uranium - isolation & purification; Radioactive pollution; Nanoparticle; Zerovalent metal; Iron; Radioisotope; Heavy metal; Contaminated site remediation; Trace element; Uranium; Decontamination; Batchwise; Water pollution; Kinetics; Nanostructured materials; Ground water
• ISSN: 0013-936X; 1520-5851; 1520-5851
• DOI: 10.1021/es9036308

This study investigated the influences of pH, bicarbonate, and calcium on U(VI) removal and reduction by synthetic nanoscale zerovalent iron (nanoFe0) particles under anoxic conditions. The results showed that the rates of U(VI) removal and reduction by nanoFe0 varied significantly with pH and concentrations of bicarbonate and/or calcium. For instance, at pH 6.92 the pseudo-first-order rate constants of U(VI) removal decreased by 78.5% and 81.3%, and U(VI) reduction decreased by 90.3% and 89.3%, when bicarbonate and calcium concentrations were increased from 0 to 1 mM, respectively. X-ray photoelectron spectroscopy (XPS) analysis confirmed the formation of UO2 and iron (hydr)oxides as a result of the redox interactions between U(VI) and nanoFe0. The study demonstrated the potential of using nanoFe0 for U(VI)-contaminated site remediation and highlighted the impacts of pH, bicarbonate, and calcium on the U(VI) removal and reduction processes.