AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Comprehensive Two-Dimensional Gas Chromatography Mass Spectrometry with Solid-state Thermal Modulator for In-situ Speciated Measurement of Organic Aerosols
ZHAOJIN AN, Haixia Ren, Mo Xue, Xiaosheng Guan, Jingkun Jiang, Tsinghua University, China
Abstract Number: 171 Working Group: Instrumentation and Methods
Abstract Thermal desorption aerosol GC/MS (TAG) is capable of online identifying speciated organics in atmospheric aerosols. Compared to reported quartz filter-based TAG (Ren et al. 2019a; 2019b), application of comprehensive two-dimensional gas chromatography increases resolution and sensitivity, mitigates unresolved complex mixture and co-elution, hence provides more accurate qualitative and quantitative information of organic aerosols. We report a quartz filter-based thermal desorption aerosol comprehensive two-dimensional GC/MS (2D-Q-TAG) which combines a solid-state thermal modulator with a quartz filter-based thermal desorption aerosol GC/MS. 2D-Q-TAG allows for in-situ automatic measurement of speciated organics in atmospheric aerosols with hourly time resolution. The solid-state thermal modulator conducts modulation independent of GC oven without using cryogens or compressed air, which makes 2D-Q-TAG readily adaptive for field measurement. The system was evaluated using C7-C40 n-alkanes and 16 polycyclic aromatic hydrocarbons (PAHs). 2D-Q-TAG shows good performance with low limit of detection (LOD) of C13-C40 n-alkanes and 16 PAHs ranging from 0.001-0.104 ng. It was then deployed to measure structured chromatograms of ambient PM2.5 in Beijing. Less unresolved complex mixture and increased chemical resolution of this instrument can facilitate the characterization of atmospheric aerosol chemical composition.
[1] Ren et al., 2019a, J Chromatogr A, 1589: 141-148. [2] Ren et al., 2019b, J Chromatogr A, in press (https://doi.org/10.1016/j.chroma.2019.04.045).