Hi Peter,

I got in trouble and I am out of schedule. But I bear in mind the samples
for You.


Concerning Your question I can say that we used hydrogen, too (purging the
copper tube from the end to the beginning of normal flow direction; tube
was heated to 600°C (usual temp.) so that the re-oxidation of copper could
take place.

Since a few weeks we are using "Formiergas" (90% N2, 10% H2); we are not
sure if it takes a litte bit longer to regenerate the column but it works,
too. We´ve got no further experiences if this method has got an influence
of the durability of the copper or any influence at the analysis.


Best wishes and good luck!
(I am hurrying.... ;-) )


Deborah