Uranium 777 Compounds

The actinide elements are a group of chemically similar elements with atomic numbers 89 through 103 and their names, symbols, atomic numbers, and discoverers are given in Table 1 (1-3) (see Thorium and thorium compounds Uranium and uranium compounds Plutonium and plutonium compounds Nuclear reactors and Radioisotopes). 

The simple box-type mixer—settler (113) has been used extensively in the UK for the separation and purification of uranium and plutonium (114). In this type of extractor, interstage flow is handled through a partitioned box constmction. Interstage pumping is not needed because the driving force is provided by the density difference between solutions in successive stages (see Plutoniumand plutonium compounds Uraniumand uranium compounds). 

Fluorine reacts with the halogens and antimony to produce several compounds of commercial importance antimony pentafluoride [7783-70-2J, bromine trifluoride [7787-71 chlorine trifluoride [7790-91 -2J, and iodine pentafluoride [7783-66-6J. Chlorine trifluoride is used in the processing of UF (see Uraniumand uranium compounds). Bromine trifluoride is used in chemical cutting by the oil well industry (see Petroleum). Antimony and iodine pentafluorides are used as selective fluorinating agents to produce fluorochemical intermediates (see Fluorine compounds, inorganic). 

Uranium is converted by CIF, BiF, and BrP to UF. The recovery of uranium from irradiated fuels has been the subject of numerous and extensive investigations sponsored by atomic energy agencies in a number of countries (55—63). The fluorides of the nuclear fission products are nonvolatile hence the volatile UF can be removed by distiUation (see Nuclearreactors Uraniumand uranium compounds). 

The uranium ore from Elliot Lake, Canada, contains yttrium and lanthanides (see Uranium and uranium compounds). In the Jiangxi province of the People s Repubhc of China a large reserve of a rare-earth-containing clay contains over 1,000,000 t of REO. This ore is characterized by having a low cerium content (<5%) but a high content in samarium, europium, terbium, and yttrium compared to the main base REO ores (Table 6). ... 

Laser isotope separation techniques have been demonstrated for many elements, including hydrogen, boron, carbon, nitrogen, oxygen, sHicon, sulfur, chlorine, titanium, selenium, bromine, molybdenum, barium, osmium, mercury, and some of the rare-earth elements. The most significant separation involves uranium, separating uranium-235 [15117-96-1], from uranium-238 [7440-61-1], (see Uranium and uranium compounds). The... 

URANIUM compounds), Pb from the thorium series, and Pb from the actinium series (see Actinides and transactinides). The crystal stmcture of lead is face-centered cubic the length of the edge of the cell is 0.49389 nm the number of atoms per unit cell is four. Other properties are Hsted in Table 1. 

The abihty of magnesium metal to reduce oxides of other metals can be exploited to produce metals such as zirconium, titanium [7440-32-6] and uranium [7440-61-1] (see ZiRCONiUMAND ZIRCONIUM COMPOUNDS Titaniumand titanium alloys Uraniumand uranium compounds). These reactions are... 

Table 1 gives the average metal content of the earth s cmst, ore deposits, and concentrates. With the exceptions of the recovery of magnesium from seawater and alkaU metals from brines, and the solution mining and dump or heap leaching of some copper, gold, and uranium (see Uranium and uranium compounds), most ores are processed through mills. Concentrates are the raw materials for the extraction of primary metals. 

U02(C02) 3. The pregnant solution is concentrated and purified by ion exchange or solvent extraction, yielding a stripping solution of ca 50 kg/m U Og. Uranium is then precipitated chemically. Pure U Og is obtained by calcination (see Uraniumand URANIUM COMPOUNDS). 

Handling of soluble uranium compounds requires appropriate clothing to prevent skin contact and eye protection to prevent any possible eye contact. Protective clothing requirements for insoluble uranium compounds should prevent repeated or prolonged skin contact. Eye protection for use in handling insoluble uranium compounds should prevent any possibiUty of eye contact. Respirators should always be worn to prevent inhalation of uranium dust, fumes, or gases (38). 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

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