Deuterophosphoric acid

Tritium was first prepared in the Cavendish Laboratory by Rutherford, OHphant, and Harteck in 1934 (2,3) by the bombardment of deuterophosphoric acid using fast deuterons. The D—D nuclear reaction produced tritium ( D-H D — -H energy), but also produced some He by a... 

Anhydrous deuterophosphoric acid can be prepared by condensing the stoichiometric amount of heavy water onto phosphorus(Y) oxide in a vacuum line. The mixture is warmed to complete the reaction and fractionally crystallized to constant melting point. The method can also be used to prepare crystalline orthophosphoric acid, H3P04, and when only small quantities are required, is preferable to methods involving the dehydration of aqueous solutions of the acid.1... 

Tube E is drawn off at point 6 and immersed in a bath at 95 to 100° for 3 days to complete the hydrolysis. The product at this stage (m.p. 42.6°) has the stoichiometry D3PO4 but contains, besides deuterophosphoric acid, small equilibrium concentrations of polyphosphates such as D30+-D3P2O7-.2 These can be removed, if so desired, by sealing the compound into one limb of an evacuated U-tube and subjecting it to repeated, slow, fractional crystallization, the last fraction of liquid being decanted each time into the second limb before the bulk of the solid, except for a seed... 

Pure deuterophosphoric acid is stable indefinitely as a solid but in the fused state always contains traces of pyro-and other polyphosphates which depress the freezing point of the compound. Its chemical properties are similar to those of phosphoric acid. The more important physical properties of the two compounds (supercooled) are compared in the following table.3... 

About 10 g. of pure sulfur(VI) oxide is prepared in the apparatus shown in Fig. 13. Concentrated oleum is placed in flask A which is cooled, evacuated, and sealed at point 1. Tube B is cooled in liquid air until the required amount of sulfur(VI) oxide has distilled over it is then sealed at point 2. Further purification of the trioxide by vacuum distillation is usually unnecessary. The procedure for reaction of the oxide with the required amount of heavy water (2.5018 g./lO g. SOs) is similar to that described in the preparation of deuterophosphoric acid except that sulfur(VI) oxide, being more volatile than phosphorus (V) oxide, should be cooled to —78° before being placed in the side arm of Fig. 14. An inert Fluorlube tap grease is recommended. Limb E is cooled and the apparatus evacuated slowly to prevent volatilization and entrainment of sulfur (VI) oxide in the vacuum line. When the oxide has been completely... 

Deuterium azide, DN3, was made from deuterophosphoric acid and sodium azide, either by dropping the acid onto the azide [43,44], or by adding dropwise a solution of sodium azide in deuterium oxide to the deuterophosphoric acid [45]. The Guenther-Meyer reaction, using deuterostearic acid, was also used [46]. 

TABLE 5.9 Properties of Phosphoric and Deuterophosphoric Acids H3PO4 D3PO4... 

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