Nitrate eutectics

The acid-base properties of fused alkali nitrates were first noted when dichromate was added to fused sodium-potassium nitrate eutectic (/)/. Gaseous nitrogen dioxide and oxygen were slowly given off with the conversion of the dichromate to chromate. It was postulated that N02+ was formed as intermediate ... 

Kust (4) has potentiometrically determined the equilibrium constant for carbonate dissociation in fused sodium-potassium nitrate eutectic ... 

Both lithium chlorate and perchlorate have been proposed as oxidizers in explosive formulations [131]. Li nitrate/K nitrate/Na nitrate eutectics (23.5/60.2/16.3) have been proposed by Kruse as oxidizers in illuminating flare formulations [132]. Similarly, LiC104 has been proposed as an oxidizer in obscurant formulations with or boron carbide(B4C) or Si. The obscuring power is mainly due to the presence of hygroscopic LiCl in the aerosol. The formulation B/LiC104 (60/40) possesses the best performance [133-135] compared with Si/Li C104 (35/65) and B4C/Li C104 (30/70) formulations. 

The absorption spectra of some rare earths and actinides in a molten LiNOs—KN03 eutectic have been measured [590, 591]. A comparison of the oscillator strength of the 4650 A band 7Fo 5Dz) in DCIO4 and the molten nitrate eutectic shows an increase [510] of —18 times in the latter solvent. Incidentally, the 7Fo 02 transition is a hypersensitive transition [580]. Carnall et al. [591] were able to observe some transitions between the ground state multiplets viz. 7Fo - 7F, 7F - 7F and 7Fo 7F at 4610,4930 and 3910 cm-1 respectively in the nitrate eutectic. 

Transition Probabilities in the Absorption and Fluorescence Spectra of Lanthanides in Molten Lithium Nitrate-Potassium Nitrate Eutectic, W.T. Camall, J.P. Hessler, and... 

Alkali metal chloride and nitrate eutectic mixtures that melt in the range 200-500°C are widely used as fused-salt solvents, because they have a large liquid range from their melting to their boiling points, and because they can be used at temperatures below the softening point of glass. 

The silver-silver Ion electrode. Of the reversible metal electrodes, silver has been most often employed. There is only one stable oxidation state of silver above 300°C there is no danger of oxide formation because Ag20 is unstable.57 The metal has no observable tendency to dissolve in molten silver salts and is highly reversible in mixed chloride and nitrate eutectics. The Ag(I) ion can be introduced into the melt by either adding silver nitrate to a nitrate melt (AgCl to a chloride melt) or by anodizing a silver electrode. The potentials of silver nitrate concentration cells show ideal thermodynamic behavior up to 0.5 mol % in (Na,K)N03 eutectic and in NaN03.58... 

Much less work has been reported for the 6-valent elements as compared with the volume of literature for the actinides in lower valence states. Hydrated neptunium and plutonium trioxides are now known, Np03 H2O and PUO3 (0.8)H2O being readily obtained by the action of ozone on an aqueous suspension of neptunium (V) or plutonium (IV) hydroxides at 90°C. (23) Np03 2H2O is obtained in a similar manner at 18°C. (23) or by ozone oxidation of neptunium (V) in a molten lithium-potassium nitrate eutectic at 150°C. (42). 

Uranium Dioxide in Molten Lithium Nitrate/Potassium Nitrate Eutectic. The behavior of uranium dioxide in a molten lithium nitrate/potassium nitrate eutectic was investigated. Our goal was to determine whether a soluble uranium species could be produced using a nitric-acid vapor sparge. The materials used were a lithium nitrate/potassium nitrate eutectic mixture, pure nitric acid (100% HNO3), and powdered uranium dioxide. The mass ratio of uranium dioxide to the nitrate melt was 1 100. 

The results of the test showed that the uranium dioxide produced a vigorous reaction with the nitrate melt, beginning at approximately 400°C. At this time the melt was open to the atmosphere, and no nitric acid was being added. Nitrogen dioxide was evolved as a gaseous product of the reaction, but there was no visual indication of any uranium solubility in the molten nitrate eutectic. Complete reaction, indicated by the cessation of gas evolution, required approximately 2.5 hours at 500°C. 

The product obtained from the lithium nitrate-potassium nitrate eutectic is neither identifiable as the diuranate (U2O7 ) or uranate (UO4 ) species, nor as a mixture composed of each of these species. To date, the x-ray powder diffraction pattern has not been identified with any known compound. It is interesting to note the ratios of the alkali metals for this system, however approximately a 2 1 atomic... 

It has been reported that in a lithium-potassium nitrate eutectic, Mn " is stabilized as a blue suspension in solutions containing OH, ... 

A. Baraka, A. Abdel Rahman, A. El-Hosary, Corrosion of mild steel in molten sodium nitrate-potassium nitrate eutectic, Br. Corros. J. 11 (1976) 44—46. 

Figure 3 Separation of Inorganic Ions by zone electrophoresis at 160°C In molten lithium nitrate-potassium nitrate eutectic containing 10% ammonium nitrate to inhibit precipitation of metal oxides. Sample applied at A. (Reproduced with permission from Alberti G and Allulli S (1968) Chromatography Reviews 10 99-128.)...

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