The interactions between contaminations of U(VI) and silicon oxide nanoparticles (SONPs), both of which have been widely used in modern industry and induced serious environmental challenge due to their high mobility, bioavailability, and toxicity, were studied under different environmental conditions such as pH, temperature, and natural organic matters (NOMs) by using both batch and spectroscopic approaches. The results showed that the accumulation process, i.e., sorption, of U(VI) on SONPs was strongly dependent on pH and ionic strength, demonstrating that possible outer- and/or inner-sphere complexes were controlling the sorption process of U(VI) on SONPs in the observed pH range. Humic acid (HA), one dominated component of NOMs, bounded SONPs can enhance U(VI) sorption below pH~4.5, whereas restrain at high pH range. The reversible sorption of U(VI) on SONPs possibly indicated that the outer-sphere complexes were prevalent at pH 5. However, an irreversible interaction of U(VI) was observed in the presence of HA (Fig 1). It was mainly due to the ternary SONPs-HA-U(VI) complexes (Type A Complexes). After SONPs adsorbed U(VI), the particle size in suspension was apparently increased from ~240 nm to ~350 nm. These results showed that toxicity of both SONPs and U(VI) will decrease to some extent after the interaction in the environment. These findings are key for providing useful information on the possible mutual interactions among different contaminants in the environment.
Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou, Gansu, 730000, China;Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou, Gansu, 730000, China;Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, Sichuan, 621000, China;Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou, Gansu, 730000, China;Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou, Gansu, 730000, China;Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou, Gansu, 730000, China;Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou, Gansu, 730000, China;Key Laboratory of Petroleum Resources, Gansu Province / CAS Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou, Gansu, 730000, China;Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou, Gansu, 730000, China;Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou, Gansu, 730000, China
Recommended Citation:
Hanyu Wu,Ping Li,Duoqiang Pan,et al. Interactions between Silicon Oxide Nanoparticles (SONPs) and U(VI) Contaminations: Effects of pH, Temperature and Natural Organic Matters[J]. PLOS ONE,2016-01-01,11(3)