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Iodide-nitric acid system

The thermal gradient (with AT of 0.005-0.008 °C) in the iodide-nitric acid system is much smaller than in the iodate-arsenous acid system (where AT = 0.7 °C). The thermal gradient plays no significant role in the former system as long as Ap < 0. The isothermal volume changes are comparable in the two systems. [Pg.201]

Nagy, I. P. Keresztessy, A. Pojman, J. A. Bazsa, G. Noszticzius, Z. 1994. Chemical Waves in the Iodide-Nitric Acid System, J. Phys. Chem. 98, 6030-6037. [Pg.374]

The aHphatic iodine derivatives are usually prepared by reaction of an alcohol with hydroiodic acid or phosphoms trHodide by reaction of iodine, an alcohol, and red phosphoms addition of iodine monochloride, monobromide, or iodine to an olefin replacement reaction by heating the chlorine or bromine compound with an alkaH iodide ia a suitable solvent and the reaction of triphenyl phosphite with methyl iodide and an alcohol. The aromatic iodine derivatives are prepared by reacting iodine and the aromatic system with oxidising agents such as nitric acid, filming sulfuric acid, or mercuric oxide. [Pg.366]

E. Peligot said that after being melted, the peroxide requires a much lower temp, for its solidification, for at —16° the compound remains liquid, and J. Fritzsche said that it can be re-solidified only at —30° because a little nitric acid has been formed, and this also accounts for the turbidity of the cooling liquid. For the fusion curve with nitric oxide, vide supra, nitrogen trioxide. P. Pascal studied the f.p. of binary systems of nitrogen peroxide with bromoform, chloroform, carbon tetrachloride, bromobenzene, methyl iodide, chloropicrin, and camphor. [Pg.535]

The main release of gaseous radionuclides occurs when UNF is breached and dissolved in boiling nitric acid. The following radionuclides iodine-129 (1-129), and krypton-85 (Kr-85) are likely to appear in the off-gas of an air sparge of the dissolver in a conventional PUREX fuel-reprocessing flowsheet. Iodine in the fuel element is believed to occur mainly as iodide (I") however, when contacted with nitric acid, the iodide rapidly oxidizes to elemental I2. Much of the elemental iodine is volatilized to the off-gas, but a portion remains dissolved in solution this ratio (gas phase/liquid phase) is the distribution coefficient or sometimes expressed as a Henry s Law constant. Further oxidation of the liquid phase iodine results in the formation of fhe nonvolatile iodate ion, IO3". However, the formation of the iodate ion occurs slowly and reduction back to elemental iodine is promoted by nitrous acid, which is present in the dissolver system (McKay, Miquel, and White, 1982). [Pg.419]

In the feed preparation step, uranyl sulfate solution from the reactor core and thorium oxide from the blanket system, freed of D2O and suspended in ordinary water, are fed into the dissolver tank. The di.s.solvent is 13 N nitric acid to which has been added catalytic amounts (0.04 N) of sodium fluoride. When short-cooled thorium is being processed, potassium iodide is added continuously to the dissolver to provide for isotopic dilution of the large amount of fission-produced which is present. The dissolver solution is continuously sparged with air, and the volatilized iodine is removed from the off-gases in a caustic scrubber. [Pg.333]

The reaction is carried out in a threenecked flask equipped with a stirrer, a dropping funnel, and an outlet for toxic nitric oxide to carry the gas to an exhaust system. A 20% aqueous solution of sodium nitrite containing about 1.5 g of the salt per 1 g of sodium azide is added onto a 5% aqueous solution of sodium azide. This is followed by slow addition of 20% sulfuric acid, until the mixture is acidic. The decomposition is complete when starch-iodide paper turns blue, indicating the presence of excess nitrite. The reaction mixture is washed down the sink with a large volume of water. [Pg.618]


See other pages where Iodide-nitric acid system is mentioned: [Pg.200]    [Pg.200]    [Pg.201]    [Pg.200]    [Pg.200]    [Pg.201]    [Pg.409]    [Pg.397]    [Pg.288]    [Pg.483]    [Pg.1079]    [Pg.1067]    [Pg.302]    [Pg.481]    [Pg.269]    [Pg.23]    [Pg.97]    [Pg.69]    [Pg.420]    [Pg.7]    [Pg.351]    [Pg.1098]    [Pg.219]    [Pg.240]   
See also in sourсe #XX -- [ Pg.200 ]




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