Coupling of gas chromatography and molecular beam mass spectrometry analytical techniques: Application to flame structure study

A new experimental technique coupling both molecular beam and mass spectrom etry (MBMS) and gas chromatography (GC) is developed to improve the analysi s of low pressure reactive systems using a probe sampling procedure. The se nsitivity of gas chromatography is greatly enhanced by using a compression procedure for the samples before injection into the chromatograph, and its selectivity allows one to separate isomers and to study very complex mixtur es. By contrast MBMS is well suited to atoms and radical species detection. Moreover, the temperature dependence of the fragmentation pattern of heavy hydrocarbons during MBMS ionization is pointed out and it can be resolved alternatively by GC calibration. The complementarity of these two analytica l techniques is demonstrated in the case of low pressure natural gas flames study. (C) 1999 American Institute of Physics. [S0034-6748(99)04106-4].