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 spectrometry (MBMS) and gas chromatography (GC) is developed to improve the analysis of low pressure reactive systems using a probe sampling procedure. The sensitivity 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 mixtures. 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 analytical techniques is demonstrated in the case of low pressure natural gas flames study.