Uranium carbonate

Uranium carbonate

Chembox new
Name = Uranium carbonate
ImageFile = Uranium carbonate.png ImageName = Uranium carbonate
IUPACName = Uranium carbonate
OtherNames = Uranyl Carbonate
Section1 = Chembox Identifiers
CASNo =
Section2 = Chembox Properties
Formula = UO2(CO3)
MolarMass = 330 g/mol
Density =
Solvent = other solvents
SolubleOther =
MeltingPt =
BoilingPt =

Uranium carbonate, UO2(CO3), is a carbonate of uranium that forms the backbone of several uranyl mineral species such as Andersonite, McKelveyite and Wyartite and most importantly Rutherfordine. It is also found in both the mineral and organic fractions of coal and its fly ash and is the main component of uranium in mine tailing seepage water.

Uranium like other actinides readily forms a dioxide uranyl core (UO2). In the environment, this uranyl core readily complexes with carbonate to form charged complexes. Although uranium forms insoluble solids or adsorbs to mineral surfaces at alkaline pH it is these soluble carbonate complexes that increase its solubility, availability, and mobility with low affinities to soil. Uranium(VI) generally forms a pH-dependent suite of uranyl-carbonate complexes in ground water solutions:

*UO2(OH)2+1
*UO2(CO3)2-2
*UO2(CO3)3-4
*UO2(CO3)(OH)3-1

A common method for concentrating uranium from a solution uses solutions of uranyl carbonates which are passed through a resin bed where the complex ions are transferred to the resin by ion exchange with a negative ion like chloride. After build-up of the uranium complex on the resin, the uranium is eluted with a salt solution and the uranium is precipitated in another process.

The uranyl carbonate minerals

Uranyl-carbonate complexes form a large class of mineral species. Several have been described in literature. These include:

*Andersonite (Hydrated Sodium Calcium Uranyl Carbonate)
*Astrocyanite-(Ce) (Hydrated Copper Cerium Neodymium Lanthanum Praseodymium Samarium Calcium Yttrium Uranyl Carbonate Hydroxide)
*Bayleyite (Hydrated Magnesium Uranyl Carbonate)
*Bijvoetite-(Y) (Hydrated Yttrium Dysprosium Uranyl Carbonate Hydroxide)
*Fontanite (Hydrated Calcium Uranyl Carbonate)
*Grimselite (Hydrated Potassium Sodium Uranyl Carbonate)
*Joliotite (Hydrated Uranyl Carbonate)
*Liebigite (Hydrated Calcium Uranyl Carbonate)
*McKelveyite (Hydrated Barium Sodium Calcium Uranium Yttrium Carbonate)
*Metazellerite (Hydrated Calcium Uranyl Carbonate)
*Rabbittite (Hydrated Calcium Magnesium Uranyl Carbonate Hydroxide)
*Roubaultite (Copper Uranyl Carbonate Oxide Hydroxide)
*Rutherfordine (Uranyl Carbonate)
*Schrokingerite (Hydrated Sodium Calcium Uranyl Sulfate Carbonate Fluoride)
*Shabaite (Hydrated Copper Cerium Neodymium Lanthanum Praseodymium Samarium Calcium Yttrium Uranyl Carbonate Hydroxide)
*Sharpite (Hydrated Calcium Uranyl Carbonate Hydroxide)
*Swartzite (Hydrated Calcium Magnesium Uranyl Carbonate)
*Voglite (Hydrated Calcium Copper Uranyl Carbonate)
*Wyartite (Hydrated Calcium Uranyl Carbonate Hydroxide)
*Widenmannite (Lead Uranyl Carbonate)
*Zellerite (Hydrated Calcium Uranyl Carbonate)
*Znucalite (Hydrated Calcium Zinc Uranyl Carbonate Hydroxide)

References

* [http://greenwood.cr.usgs.gov/energy/factshts/163-97/FS-163-97.html Radioactive Elements in Coal and Fly Ash]
* [http://www.nrc.gov/reading-rm/basic-ref/glossary/ion-exchange.html Ion-exchange, U.S. Nuclear Regulatory Commission]
* [http://www.swwrc.wsu.edu/reports/WRR-04.pdf Remediation of Uranium Contaminated Mine Waste]
* [http://mineral.galleries.com/minerals/carbonat/class.htm The Mineral Gallery - Uranyl Carbonates]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • Uranium — (pronEng|jʊˈreɪniəm) is a silvery gray metallic chemical element in the actinide series of the periodic table that has the symbol U and atomic number 92. It has 92 protons and 92 electrons, 6 of them valence electrons. It can have between 141 and …   Wikipedia

  • Carbonate mixte d'ammonium et d'uranyle — Constituants d un AUC Général Synonymes trica …   Wikipédia en Français

  • Uranium in the environment — Uranium in the environment, this page is about the science of uranium in the environment and in animals (including humans). The legal and social issues associated with uranium are discussed elsewhere. This page is a subpage of actinides in the… …   Wikipedia

  • Uranium-thorium dating — Uranium thorium dating, also called thorium 230 dating, uranium series disequilibrium dating or uranium series dating, is a radiometric dating technique commonly used to determine the age of carbonate materials such as speleothem or coral [ [http …   Wikipedia

  • uranium processing — Introduction       preparation of the ore for use in various products.       Uranium (U), although very dense (19.1 grams per cubic centimetre), is a relatively weak, nonrefractory metal. Indeed, the metallic properties of uranium appear to be… …   Universalium

  • Uranium mining — The Ranger Uranium Mine in Australia …   Wikipedia

  • carbonate mineral — Any member of a family of minerals that contains the carbonate ion, CO32 , as the basic structural unit. The carbonates are among the most widely distributed minerals in the earth s crust; the most common are calcite, dolomite, and aragonite.… …   Universalium

  • Ammonium uranyl carbonate — Chembox new Name = Ammonium uranyl carbonate IUPACName = uranium(VI)dioxide di ammonium carbonate OtherNames = uranyl ammonium carbonate Section1 = Chembox Identifiers Section2 = Chembox Properties Formula = UO2CO3·2(NH4)2CO3 MolarMass = 522.199… …   Wikipedia

  • Principal cosmogenic and uranium-thorium series radioisotopes — ▪ Table Principal cosmogenic and uranium thorium series radioisotopes radioisotope half life in years principal uses Cosmogenic isotope beryllium 10 1.5(106) dating marine sediment, manganese nodules, glacial ice, quartz in rock exposures,… …   Universalium

  • Actinide — The atomic bomb dropped on Nagasaki had a plutonium charge.[1] The actinide or actinoid (IUPAC nomenclature) series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium thro …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”