Try using a lower grade of H2 gas. The problem is that UHP tanks are not
refilled as frequently as lower grade H2 tanks.
The "good" H2 tanks for IRMS have accumulated traces of HD with each filling.
A tank that has been refilled multiple times will have the value that you are
Call the area distribution office and explain that you are looking for older
tanks, and that you wish to be able to return the full tanks that have H/D
that are not in your required range. You might need to try 3-4 tanks but you
will eventually find one that will last for years.
And then you add a drying cartridge--no need for UHP.
In MA we used Middlesex Welding as they were happy to accommodate this
kind of request.
On Wed, 18 Nov 2009 13:50:33 -0500, Heather Graham <[log in to unmask]>
> I am trying to find UHP hydrogen gas made from natural gas with D/H
>between -100 and -300. This is for use as a reference gas for GC-
>pyrolysis-IRMS. We received a tank of hydrogen probably made by water
>electrolysis with D/H of -860. Our supplier claims they cannot
>guarantee provenance of the gases but if anyone has an idea where I
>could specially order steam reform in the NorthEast US that would be