A compact PTR-ToF-MS instrument for airborne measurements of volatile organic compounds at high spatiotemporal resolution

作者：Mueller M; Mikoviny T; Feil S; Haidacher S; Hanel G; Hartungen E; Jordan A; Maerk L; Mutschlechner P; Schottkowsky R; Sulzer P; Crawford J H; Wisthaler A^*

来源：Atmospheric Measurement Techniques, 2014, 7(11): 3763-3772.

DOI：10.5194/amt-7-3763-2014

Herein, we report on the development of a compact proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) for airborne measurements of volatile organic compounds (VOCs). The new instrument resolves isobaric ions with a mass resolving power (m/Delta m) of similar to 1000, provides accurate m/z measurements (Delta m < 3 mDa), records full mass spectra at 1 Hz and thus overcomes some of the major analytical deficiencies of quadrupole-MS-based airborne instruments. 1 Hz detection limits for biogenic VOCs (isoprene, alpha total monoterpenes), aromatic VOCs (benzene, toluene, xylenes) and ketones (acetone, methyl ethyl ketone) range from 0.05 to 0.12 ppbV, making the instrument well-suited for fast measurements of abundant VOCs in the continental boundary layer. The instrument detects and quantifies VOCs in locally confined plumes (< 1 km), which improves our capability of characterizing emission sources and atmospheric processing within plumes. A deployment during the NASA 2013 DISCOVER-AQ mission generated high vertical- and horizontal-resolution in situ data of VOCs and ammonia for the validation of satellite retrievals and chemistry transport models.

• 出版日期2014