Characterization of primary and aged wood burning and coal combustion organic aerosols in an environmental chamber and its implications for atmospheric aerosols

Abstract

Abstract. Particulate matter (PM) affects visibility, climate, and public health. Organic matter (OM), a uniquely complex portion of PM, can make up more than half of total atmospheric fine PM mass. We investigated the effect of aging on secondary organic aerosol (SOA) concentration and composition for wood burning (WB) and coal combustion (CC) emissions, two major atmospheric OM sources, using mid-infrared (MIR) spectroscopy and aerosol mass spectrometry (AMS). For this purpose, primary emissions were injected into an environmental chamber and aged using hydroxyl (diurnal aging) and nitrate (nocturnal aging) radicals to reach an atmospherically relevant oxidative age. A time-of-flight AMS instrument was used to measure the high-time-resolution composition of non-refractory fine PM, while fine PM was collected on PTFE filters before and after aging for MIR analysis. AMS and MIR spectroscopy indicate an approximately 3-fold enhancement of organic aerosol (OA) concentration after aging (not wall-loss corrected). The OM:OC ratios also agree closely between the two methods and increase, on average, from 1.6 before aging to 2 during the course of aging. MIR spectroscopy, which is able to differentiate among oxygenated groups, shows a distinct functional group composition for aged WB (high abundance of carboxylic acids) and CC OA (high abundance of non-acid carbonyls) and detects aromatics and polycyclic aromatic hydrocarbons (PAHs) in emissions of both sources. The MIR spectra of fresh WB and CC aerosols are reminiscent of their parent compounds with differences in specific oxygenated functional groups after aging, consistent with expected oxidation pathways for volatile organic compounds (VOCs) of each emission source. The AMS mass spectra also show variations due to source and aging that are consistent with the MIR functional group (FG) analysis. Finally, a comparison of the MIR spectra of aged chamber WB OA with that of ambient samples affected by residential wood burning and wildfires reveals similarities regarding the high abundance of organics, especially acids, and the visible signatures of lignin and levoglucosan. This finding is beneficial for the source identification of atmospheric aerosols and interpretation of their complex MIR spectra.

Chemical evolution of primary and secondary biomass burning aerosols during daytime and nighttime

“…As stated in the previous Section, OA concentrations of AMS (without CE correction) and FTIR were correlated R 2 = 0.75, with OM:OC also showing similar trends upon aging. The spectral features and chemical composition of primary wood burning aerosols from FTIR -and mass fragment profiles from AMS -in this work are consistent with that previously reported (e.g., Tiitta et al, 2016;Bertrand et al, 2017Bertrand et al, , 2018aYazdani et al, 2021c). The FTIR spectra of these primary aerosols largely resemble that of wood constituents such as lignin (Yazdani et al, 2021c).…”

“…A multiple peak-fitting algorithm was applied on the FTIR spectra to estimate abundances of alcohol (referred to as aCOH), carboxylic acid (COOH), alkane (aCH), and non-acid carbonyl (naCO) groups (Takahama et al, 2013). The ratio of fingerprint absorbances related to levoglucosan (multiple peaks in the 860-1050 cm −1 range; Yazdani et al, 2021c) and lignin-like compounds (single sharp peak at 1515 cm −1 ) in the FTIR spectra were compared between primary and aged aerosols to estimate the change of these two biomass burning markers with aging. Absolute levoglucosan concentrations were estimated using the mentioned fingerprint absorbances, with absorption coefficient estimated from measurements of Ruthenburg et al (2014).…”

“…Fine particulate matter (PM) in the atmosphere impacts climate and visibility (McFiggans et al, 2004;Hallquist et al, 2009) and is known to cause respiratory and cardiovascular diseases, leading to premature mortality (Pope et al, 2009;Shiraiwa et al, OA mass concentration and elemental ratios (Coury and Dillner, 2008;Ruthenburg et al, 2014;Reggente et al, 2016;Boris et al, 2019). A recent study also shows the ability of FTIR to quantify bbOA marker molecules (Yazdani et al, 2021c).…”

Importance of Semivolatile/Intermediate-Volatility Organic Compounds to Secondary Organic Aerosol Formation from Chinese Domestic Cooking Emissions

“…Considering the dilution ratio, the average SOA formation efficiency was (6.1 ± 0.4) × 10 –16 μg molecules –1 s –1 for cooking emissions. This SOA formation efficiency is lower than that of vehicle exhaust, biomass burning, and coal combustion, which are 7.4 × 10 –12 , 1.1 × 10 –14 , and 6.7 × 10 –15 μg molecules –1 s –1 , respectively. But it is higher than the negligible SOA formation efficiency of scrubbed shipping emissions .…”

Quantification of major particulate matter species from a single filter type using infrared spectroscopy – Application to a large-scale monitoring network

“…Organic absorption bands are useful for measuring OC but also provide spectral information needed to add detailed knowledge of composition not currently measured in air quality monitoring networks -such as organic matter (OM) and organic functional group compositionwhich is the subject of other work (Reggente et al, 2019;Boris et al, 2019Boris et al, , 2021Burki et al, 2020). Such calibrations, also combined with factor analytic approaches, can provide source characterization on par with more costly mass spectrometric techniques (Boris et al, 2021;Yazdani et al, 2021a;Hawkins et al, 2010;Takahama et al, 2011;Liu et al, 2012;Corrigan et al, 2013).…”