LASER MASS-SPECTROMETRY FOR TIME-RESOLVED MULTICOMPONENT ANALYSIS OF EXHAUST-GAS

A new analytical method for the fast analysis of trace substances in gas mixtures has been developed incorporating a pulsed tunable laser system and a reflectron time-of-flight mass spectrometer. The technique is especially designed for the time-resolved detection of air pollutants in the exhaust gas of motor engines. The purpose of this new analytical method is to achieve high time resolution (<100 ms), high sensitivity (down to 1 ppm), high quantitative precision (10%), and applicability to most exhaust emission components. The main difficulties for the analysis arise from the large number of components which show very different and rapidly varying concentrations. For a preliminary list of 25 exhaust emission components, all essential prameters have been determined. First results obtained from a real exhaust gas sample are presented.