Re: "Tritium on Ice"

[RuthWeiner@AOL.COM]

In a message dated 10/1/02 6:37:14 AM Mountain Daylight Time, liptonw@DTEENERGY.COM writes:



> Although tritium is one of the more innocuous radionuclides, the downside is
>
> that it's virtually impossible to contain.  It will diffuse through virtually
>
> anything.  Respiratory protection is useless, since it's absorbed through the
>
> skin.


Chemically, tritium is hydrogen.  as a gas (H2) it will indeed diffuse through ALMOST anything -- it does have slightly more van der Waals potential than helium for example.  I would guess ("engineering judgment") that it diffuses almost as readily as krypton or xenon.  However, tritium also exchanges freely with hydrogen in other compounds like water, and tritium released into the air will exchange with the hydrogen in water vapor and will then behave chemically like water vapor, not hydrogen gas. 


I had personal experience with this when I did my dissertation work (40 years ago!).  I used deuterated and tritiated organic compounds, and had to work under a nitrogen atmosphere (positive pressure) in order to avoid losing my isotopic substituents.


A number of compounds can serve as hydrogen (tritium) "getters" -- metal hydrides (tritiides) are formed readily.  When tritium is produced, it is generally trapped by a getter -- otherwise you would lose it.


Ruth  

Ruth Weiner, Ph. D.

ruthweiner@aol.com