Title: | Gas/particle partitioning of 2-methyltetrols and levoglucosan at an urban site in Denver |
Author(s): | Xie M; Hannigan MP; Barsanti KC; |
Address: | "Department of Mechanical Engineering, College of Engineering and Applied Science, University of Colorado , Boulder, Colorado 80309, United States" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "In this study, a medium volume sampler incorporating quartz fiber filters (QFFs) and a polyurethane foam (PUF)/XAD/PUF sandwich (PXP) was used to collect 2-methyltetrols (isoprene tracer) and levoglucosan (biomass burning tracer) in gaseous and particle (PM2.5) phases. The measured gas/particle (G/P) partitioning coefficients (Kp,OMm) of 2-methyltetrols and levoglucosan were calculated and compared to their predicted G/P partitioning coefficients (Kp,OMt) based on an absorptive partitioning theory. The breakthrough experiments showed that gas-phase 2-methyltetrols and levoglucosan could be collected using the PXP or PUF adsorbent alone, with low breakthrough; however, the recoveries of levoglucosan in PXP samples were lower than 70% (average of 51.9-63.3%). The concentration ratios of 2-methyltetrols and levoglucosan in the gas phase to those in the particle phase were often close to or higher than unity in summer, indicating that these polar species are semi-volatile and their G/P partitioning should be considered when applying particle-phase data for source apportionment. The Kp,OMm values of 2-methyltetrols had small variability in summer Denver, which was ascribed to large variations in concentrations of particulate organic matter (5.14 +/- 3.29 mug m-3) and small changes in ambient temperature (21.8 +/- 4.05 degrees C). The regression between log Kp,OMm and log Kp,OMt suggested that the absorptive G/P partitioning theory could reasonably predict the measured G/P partitioning of levoglucosan in ambient samples" |
Keywords: | Air Pollutants/*analysis/chemistry Cities Colorado Environmental Monitoring/instrumentation/*methods Filtration Glucose/*analogs & derivatives/analysis/chemistry Particulate Matter/analysis/chemistry Polyurethanes/chemistry Quartz Seasons Volatile Organic; |
Notes: | "MedlineXie, Mingjie Hannigan, Michael P Barsanti, Kelley C eng 2014/02/13 Environ Sci Technol. 2014; 48(5):2835-42. doi: 10.1021/es405356n. Epub 2014 Feb 21" |