Deuterium separation processes hydrogen distillation

Since 1952, most of the tritium measured in the atmosphere originates from thermonuclear explosions. Like hydrogen, deuterium and tritium also exhibit molecular isomerism. Because of the important differences between the relative atomic masses of the three isotopes, their physical properties (e.g., density, enthalpy of vaporization) differ greatly. This allows an easier isotopic separation than for any other element. Several separation processes are used for the enrichment and separation of hydrogen isotopes. Most of these processes use isotopic exchange reactions (e.g., H D-H O or NH3-HD) and to a lesser extent fractional distillation and water electrolysis (e.g., Norway, Canada). 

Distillation of Hquid hydrogen as a method for separating deuterium received early consideration (10,58) because of the excellent fractionation factor that can be attained and the relatively modest power requirements. The cryogenic temperatures, and the requirement that the necessarily large hydrogen feed be extremely pure (traces of air, carbon monoxide, etc, are soHds at Hquid hydrogen temperature) have been deterrents to the use of this process (see... 

Although the isotopes of an element have very similar chemical properties, they behave as completely different substances in nuclear reactions. Consequently, the separation of isotopes of certain elements, notably from U and deuterium from hydrogen, is of great importance in nuclear technology. The fact that isotopes of an element have such similar gross physical and chemical properties, however, makes their separation unusually difficult and has necessitated the development of processes and concepts especially adapted to this purpose. Despite the novelty of some of these isotope separation techniques, they have features in common with distillation and other famihar separation methods, and study of isotope separation is helpful in understanding more conventional separation methods. 

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