Grossenselektive Probenahme von Dieselrusspartikeln und die Bestimmung der angelagerten PAH / Size-fractioned sampling of particulate diesel emissions and determination of particle bound PAH

Particulate Diesel emissions can be size fractioned by low-pressure impactors (LPI). A comparison of the total particulate mass and the particle bound polycyclic aromatic hydrocarbons measured by LPI and filter desposition respectively, shows that the LPI cannot be used for quantification. Smallest particles are not precipitated and a desorption of volatile particle bound components appears during the test procedure. A method of detecting PAH by HPLC with a programmable fluorescence detector was developed which allows quantification of dibenzopyrenes which are not commonly measured in Diesel soot. They are found to be in the same concentration range as other PAH in Diesel soot. The chromatographic method is compared with an on-line method (Photoelectric Aerosolmonitor) already in use for the determination of imissions. A systematic comparison of the two methods shows that the assignment of the on-line signal to a chromatographic measured PAH-concentration is not unambiguous.