Quantitative IR Spectrum and Vibrational Assignments for Glycolaldehyde Vapor: Glycolaldehyde Measurements in Biomass Burning Plumes

Journal Article · Mon Apr 15 04:00:00 EDT 2013 · Journal of Physical Chemistry A, 117(20):4096-4107

DOI:https://doi.org/10.1021/jp311945p· OSTI ID:1082588

Johnson, Timothy J.; Sams, Robert L.; Profeta, Luisa T.; Akagi, Sheryl; Burling, Ian R.; Yokelson, Robert J.; Williams, Stephen D.

Glycolaldehyde (GA, 2-hydroxyethanal, C2H4O2) is a semi-volatile molecule of atmospheric importance, recently proposed as a precursor in the formation of aqueous-phase secondary organic aerosol (SOA). There are few methods to measure glycolaldehyde vapor, but infrared spectroscopy has been used successfully. Using vetted protocols we have completed the first assignment of all fundamental vibrational modes and derived quantitative IR absorption band strengths using both neat and pressure-broadened GA vapor. Even though GA is problematic due to its propensity to both dimerize and condense, our intensities agree well with the few previously published values. Using the reference ν10 band Q-branch at 860.51 cm-1, we have also determined GA mixing ratios in biomass burning plumes generated by field and laboratory burns of fuels from the southeastern and southwestern United States, including the first field measurements of glycolaldehyde in smoke. The GA emission factors were anti-correlated with modified combustion efficiency confirming release of GA from smoldering combustion. The GA emission factors (g of GA emitted per kg dry biomass burned on a dry mass basis) had a low dependence on fuel type consistent with the production mechanism being pyrolysis of cellulose. GA was emitted at 0.23 ± 0.13% of CO from field fires and we calculate that it accounts for ~18% of the aqueous-phase SOA precursors that we were able to measure.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1082588
• Report Number(s): PNNL-SA-92441; 400403209
• Journal Information: Journal of Physical Chemistry A, 117(20):4096-4107, Journal Name: Journal of Physical Chemistry A, 117(20):4096-4107
• Country of Publication: United States
• Language: English

Related Subjects

Glycolaldehyde
infrared
biomass burning
FTIR
IR band strengths