More S notes for the TC/EA:

We have been analyzing bird feathers for H isotopes. Keratin has some S in
it. After several months of running feathers our Conflo interface was
filled with yellowish "stuff" which broke the standard gas capillaries when
they went up and down. It was not fun to clean this and reassemble it. I
wonder if anyone running sulfates has seen S transfer to the glass tube in
the Conflo.

We had sulfur on the surface and throughout the glassy carbon, which we
examined with microRaman spectroscopy. Sulfur also contaminated the glassy
carbon chips at the bottom of the reactor. We have tried adding some extra
silver wool at the bottom of the glassy carbon rod to scrub out the sulfur.
What seems to be most important is to diassemble the reactor immediately
analyzing materials that contain S and expose components to air (oxygen).
This might not be a problem with sulfates, but things happen at 1450 C that
don't occur at lower temperatures.

Marilyn Fogel

Dr. Marilyn L. Fogel, Senior Scientist
Carnegie Institution of Washington
Geophysical Laboratory
5251 Broad Branch Rd., NW
Washington, DC 20015
USA
1-202-478-8981
FAX 202-478-8901
Main Office 1-202-478-8900