The behavior of molecules in different microwave induced plasmas (MIPs) has been studied by means of optical emission spectroscopy' (OES). This in order to study if MIP-OES can be used for the analysis of molecular components in incinerator gases. Various molecular species (i.e. N2, CO2, SF6, H20 and S02) have been introduced into argon or purely molecular plasmas at both atmospheric and reduced pressure. Emission from originally introduced molecules is only observed in the case of nitrogen (emission bands from the first and second positive system). Using other molecular gases, only dissociation and association products are observed (i.e. atomic species, CN, C2, CO, OH, NH). The intensity of these products has been studied as a function of the pressure, the concentration of introduced molecules and the position in the plasma. Because mainly association products are observed, is it not straightforward to analyze
molecular components in incinerator gases with MIP-OES. Moreover, emission from N2, the dominant molecule in incinerator gases, is very intense and extends from 290 to 1000 nm, covering almost this entire spectral range with bands.