Gases for Spectrometry

All gases used for spectrometry should be of such a quality that they do not introduce any uncertain elements into the analysis.

For flame atomic absorption spectrometry, a flame from acetylene and air, or acetylene and nitrous oxide is often used. The acetylene quality should be low acetone, as acetone in the instrument may lead to incorrect measurements, and cause damage to valves, connections and pipes in the control system for fuel gas. The moisture content must also be low to avoid variations in the flow.

Argon used for atomic absorption spectrometry shold have a law Oxygen and moisture content. Oxygen will “eat” the graphite used in the graphite furnace technique, and can also, in particular cases , create metal oxides which may lead to errors in the analysis. High moisture content will produce a higher background m and possible incorrect results and , in the worst case, the possibility of condensation.

For argon used for ICP, the nitrogen and moisture content should be low. Nitrogen content over 20 ppm will make it difficult to ignite the plasma, while moisture in excess of 3-5 ppm can produce unstable plasma and subsequently incorrect results.