Online measurement of polycyclic aromatic hydrocarbons by fast GC/MS

A novel system, based on gas chromatography mass spectrometry has been developed for the on-line assessment of PAH at combustion processes. The analytical results are obtained on site after minutes. Because of their wide range of volatility, PAH's always occur in a gaseous fraction and a particle adsorbed fraction. A sampling technique for the particulate fraction, based on the dilution method and filter tape sampling, has been constructed. By thermodesorption, fast GC and the combination with a membrane inlet system for the MS an analysis down to the ppb level at a cycle rate of 5 minutes has been achieved. Quick GC runs are possible because of the light weight construction of the chromatographic system. This analytical system has been tested on-site at several emission sources (oil combustion plants, coke oven and diesel engines). Analytical results demonstrate the advantages of this concept. A comparison is done with results from other methods.