The suitability of Multichannel-PDMS-Denuders for the gas-particle-partitioning of SVOCs

During the determination of hazardous occupational aerosols from semi-volatile organic compounds (SVOCs), it is important to measure both particle and gas phase. A denuder is able to separate the gas from the particle phase of an aerosol, and the collected gas can be extracted and analysed independently. In this study MultichannelPDMS-Denuders (MCD) were analysed with respect to their transmission and collection efficiency. The transmission efficiency was determined with polystyrene latex(PSL)-particles with a size of 0.3, 0.51, 0.75, 0.99,1.54 and 1.93 μm. Particle size-dependent transmission efficiencies between 93.3 to 86.7% for the 4 mm ID (inner diameter) liners (22 polydimethylsiloxane (PDMS) tubes) and 91.6 to 73.0% for the 3.29 mm ID liners (16 PDMS tubes) were measured. The experiments for the determination of the collection efficiency of MCD yielded for non-polar n-hexadecane a much higher sorption capacity (97% after 5 h, 85% after 24 h) than for polar diethylene glycol (94% after 15 min, 49% after 135 min). As a consequence, an approximately 30 times higher breakthrough volume was observed for n-hexadecane.