Reactive uptake of glyoxal by particulate matter

Abstract

[1] The uptake of gaseous glyoxal onto particulate matter has been studied in laboratory experiments under conditions relevant to the ambient atmosphere using an aerosol mass spectrometer. The growth rates and reactive uptake coefficients, g, were derived by fitting a model of particle growth to the experimental data. Organic growth rates varied from 1.05 Â 10 À11 to 23.1 Â 10 À11 mg particle À1 min À1 in the presence of $5 ppb glyoxal. Uptake coefficients (g) of glyoxal varied from 8.0 Â 10 À4 to 7.3 Â 10 À3 with a median g = 2.9 Â 10 À3 , observed for (NH 4 ) 2 SO 4 seed aerosols at 55% relative humidity.Increased g values were related to increased particle acidity, indicating that acid catalysis played a role in the heterogeneous mechanism. Experiments conducted at very low relative humidity, with the potential to be highly acidic, resulted in very low reactive uptake. These uptake coefficients indicated that the heterogeneous loss of glyoxal in the atmosphere is at least as important as gas phase loss mechanisms, including photolysis and reaction with hydroxyl radicals. Glyoxal lifetime due to heterogeneous reactions under typical ambient conditions was estimated to be t het = 5-287 min. In rural and remote areas the glyoxal uptake can lead to 5-257 ng m À3 of secondary organic aerosols in 8 hours, consistent with recent ambient measurements.Citation: Liggio, J., S.-M. Li, and R. McLaren (2005), Reactive uptake of glyoxal by particulate matter,

Distributions and diurnal changes of low molecular weight organic acids and ^|^alpha;-dicarbonyls in suburban aerosols collected at Mangshan, North China

“…α-Dicarbonyls showed concentrations ranging from 3.5 to 289 ng m -3 , with an arithmetical average of 51.5 ng m -3 in daytime and 59.8 ng m -3 in nighttime. Glyoxal (Gly) and methylglyoxal (MeGly) are gas-phase oxidation products of numerous VOCs such as benzene, toluene, xylene (Volkamer et al, 2001), ethylene (Ervens et al, 2004), isoprene (Zimmermann and Poppe, 1996) and terpene (Fick et al, 2004), and could act as precursors of secondary organic aerosols via heterogeneous processes (Kroll et al, 2005;Liggio et al, 2005).…”

Diurnal and temporal variations of water-soluble dicarboxylic acids and related compounds in aerosols from the northern vicinity of Beijing: Implication for photochemical aging during atmospheric transport

“…Gly may be associated with pollution sources whereas MeGly may be involved with biogenic sources such as isoprene. These α-dicarbonyls may serve as the precursors to produce secondary organic aerosols through heterogeneous reactions (Kroll et al, 2005;Liggio et al, 2005). Interestingly, levels of α-dicarbonyls in the Mangshan samples (3.5 to 271 ng m -3 , av.…”

On-road vehicle emissions of glyoxal and methylglyoxal from tunnel tests in urban Guangzhou, China

“…From our tunnel study we observed that average mass ratios of glyoxal-to-toluene and methylglyoxal-to-toluene were 0.1 and 0.03, respectively. Although the direct emission of glyoxal and methylglyoxal from vehicle exhausts seemed much smaller when compared to that of toluene, they would also contribute substantially to SOA due to their higher SOA formation potentials (Liggio et al, 2005;Warneck, 2005;Yu et al, 2005). The SOA yields of glyoxal and methylglyoxal were 0.56e1.20 and 0.66e0.95, respectively, against that of 0.3 for toluene (Ng et al, 2007;Lim et al, 2013;Sumner et al, 2014), so SOA formed from vehicle-emitted glyoxal and methylglyoxal altogether could reach 25.3e49.5% of SOA formed from vehicle emitted toluene.…”

“…Some carbonyls such as formaldehyde and acetaldehyde have been identified as toxic air contaminants with adverse health effects (Partridge et al, 1987). However, less attention had been paid to dicarbonyls until recently glyoxal (CHOCHO) and methylglyoxal (CH 3 C(O)CHO) were identified as important precursors of SOA through homogeneous and heterogeneous reactions (Liggio et al, 2005;Fu et al, 2008). Very recently data are accumulating about dicarbonyls in the ambient air (Dai et al, 2012;Ho et al, 2014;Li et al, 2013Li et al, , 2014.…”