Inorganic Gases

For analysis of inorganic gases, adsorbents such as molecular sieve, active alumina, active carbon and silica gel are used. For the analysis of H2 with TCD, a quantitative determination cannot be made if He is used as the carrier gas, so it is necessary to use N2 or Ar which has very different thermal conductivity (Fig. 1). Molecular Sieve is the only packing capable of separating O2 and N2 at room temperature, and is suitable for the separation of permanent gases. It easily loses its resolution if it adsorbs H2O, CO2, H2S, SO2 and NH3. Regeneration must be carried out at high temperature. For analysis of inert gases, Molecular Sieve 5A is used. For trace amount of CO analysis, consistently good results are obtained by Molecular Sieve 13X-S (Fig. 3).