Uranium environmental chemistry

Laboratory batch and column studies to evaluate Apatite II removal of soluble uranium from contaminated groundwater. American Chemical Society National Meeting, American Chemical Society, Division of Environmental Chemistry, 41, 109-113. 

Accurate uranium analysis, particularly for isotope measurements, is essential in many fields, including environmental studies, geology, hydrogeology, the nuclear industry, health physics, and homeland security. Nevertheless, only a few scientific books are dedicated to uranium in general and analytical chemistry aspects in particular. Analytical Chemistry of Uranium Environmental, Forensic, Nuclear, and Toxicological Applications covers the fascinating advances in the field of analytical chemistry of uranium. 

Carbonates. Actinide carbonate complexes are of interest not only because of their fundamental chemistry and environmental behavior (150), but also because of extensive industrial appHcations, primarily in uranium recovery from ores and nuclear fuel reprocessing. 

Scott MR (1982) The chemistry of U- and Th-series nuchdes in rivers. In Uranium series disequilibrium Application to environmental problems. Ivanovich M, Harmon RS (eds) Oxford Sciences Publications, Oxford, p 181-201... 

Cochran JK (1984) The fates of U and Th decay series nuclides in the estuarine environment. In The Estuary as a Filter. Kennedy VS (ed) Academic Press, London, p 179-220 Cochran JK (1992) The oceanic chemistry of the uranium - and thorium - series nuclides. In Uranium-series Disequilibrium Applications to Earth, Marine and Environmental Sciences. Ivanovich M, Harmon RS (eds) Clarendon Press, Oxford, p 334-395 Cochran JK, Masque P (2003) Short-lived U/Th-series radionuclides in the ocean tracers for scavenging rates, export fluxes and particle dynamics. Rev Mineral Geochem 52 461-492 Cochran JK, Carey AE, Sholkovitz ER, Surprenant LD (1986) The geochemistry of uranium and thorium in coastal marine-sediments and sediment pore waters. Geochim Cosmochim Acta 50 663-680 Corbett DR, Chanton J, Burnett W, Dillon K, Rutkowski C. (1999) Patterns of groundwater discharge into Florida Bay. Linrnol Oceanogr 44 1045-1055... 

Phosphorus is one of the most important elements in soil chemistry because it is involved in numerous reactions with many different components. In addition to the species described earlier, phosphate will also form species with uranium, arsenic, and zinc. It also reacts with organic matter and with humic and fulvic acids to form environmentally important species [33-37],... 

The elucidation of actinide chemistry in solution is important for understanding actinide separation and for predicting actinide transport in the environment, particularly with respect to the safety of nuclear waste disposal.72,73 The uranyl CO + ion, for example, has received considerable interest because of its importance for environmental issues and its role as a computational benchmark system for higher actinides. Direct structural information on the coordination of uranyl in aqueous solution has been obtained mainly by extended X-ray absorption fine structure (EXAFS) measurements,74-76 whereas X-ray scattering studies of uranium and actinide solutions are more rare.77 Various ab initio studies of uranyl and related molecules, with a polarizable continuum model to mimic the solvent environment and/or a number of explicit water molecules, have been performed.78-82 We have performed a structural investigation of the carbonate system of dioxouranyl (VI) and (V), [U02(C03)3]4- and [U02(C03)3]5- in water.83 This study showed that only minor geometrical rearrangements occur upon the one-electron reduction of [U02(C03)3]4- to [U02(C03)3]5-, which supports the reversibility of this reduction. 

If the environmental condition of the ore zone changes as a result of either natural or manmade causes, the uranium can become very mobile. This is evidenced by the in situ mining process in which relatively minor modifications are made to the ground-water chemistry to produce a solution that can rapidly dissolve uranium and maintain uranium solution concentrations of hundreds of parts per million. We have shown in our laboratory experiments that when this uranium-rich solution contacts aquifer sediments containing minerals capable of reducing uranium from (VI) to (IV), large portions of the uranium are rapidly removed from solution and immobilized. 

Bernat, M. and Church, T.M. (1989) Uranium and thorium decay series in the modern marine environment. In Handbook of Environmental Isotope Chemistry (eds Fritz, R and Fontes, J.Ch.), Chapter 10. Elsevier, Amsterdam, pp. 357-383. 

Cochran, J.K. (1992) The oceanic chemistry of the U- and Th-series nuclides. In Uranium Series Disequilibrium Applications to Environmental Sciences (Ivanovich, M., and Harmon, R.S., eds.), pp. 334-395, Clarendon Press, Oxford, UK. 

Romero G. E. T., Ordonez R. E., Esteller A. M. V., and Reyes G. L. R. (1999) Uranium behaviour through the unsaturated zone in soil. In Environmental Radiochemical Analysis, Special Publication, 234 (ed. G. W. Newton). Royal Society of Chemistry, pp. 143-151. 

Cochran J. K. (1982) The oceanic chemistry of U and Th series nuclides. In Uranium Series Disequilibrium Application to Environmental Problems (eds. M. Ivanovich and R. S. Harmon). Clarendon press, Oxford, pp. 384-430. 

Scott, M.R., The chemistry of U- and Th-series nuclides in rivers, pp. 181-201. In M. Ivanovich and R.S. Harmon (ed.) Uranium series disequilibrium applications to environmental problems. Oxford Univ. Press, Oxford, 1982. 

Carbonates. Hexavalent actinide carbonates have been very thoroughly studied by a variety of solution and solid state techniques. These complexes are of interest not only because of their fundamental chemistry and environmental behavior, but also because of extensive industrial applications, such as in uranium mining and nuclear fuel production and reprocessing. Uranyl carbonates are very soluble, very stable, and can be readily precipitated to produce powders suitable for industrial scale transformations. 

MOFs/CPs, as the majority of these materials are based on transition metal, and more recently, lanthanide chemistry, yet a review of polymeric materials containing uranium (from more of a polymer chemistry perspective) has appeared recently. We will compare and contrast some uranium specific issues to those of the transition elements as we feel that the unique coordination geometries of the actinides (in particular U(VI)) result in a number of stmctural features, synthetic challenges, relevance to environmental issues, and opportunities for development of functional materials. 

Cochran JK (1992) The oceanic chemistry of the Uranium and Thorium-series nuclides. In Ivanovich M and Harmon RS (eds.) Uranium-series Disequilibrium Applications to Earth, Marine, and Environmental... 

Detectors within this range of dimension and resolution are suitable for most environmental radioanalytical chemistry applications. The alpha-particle emitters of interest include isotopes of thorium, uranium, neptunium, plutonium, americium, and sometimes curium at 5.80 MeV). Most of the major alpha particles... 

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