AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Analysis of Unidentified Organic Species in Fresh and Aged Biomass-Burning Emissions Generated under Controlled Conditions
VERA SAMBUROVA, Deep Sengupta, Chiranjivi Bhattarai, Adam Watts, Hans Moosmuller, Andrey Khlystov, Desert Research Institute
Abstract Number: 740 Working Group: Biomass Combustion: Emissions, Chemistry, Air Quality, Climate, and Human Health
Abstract Large quantities of organic compounds are emitted into the atmosphere every day from different sources. Emissions from wildland fires and biomass fuel use contribute significantly to regional air pollution events, global-scale radiative forcing, and climate change. Global inventories of black carbon (BC) and organic carbon (OC) particulate mass emitted from combustion show that almost 90% of total carbonaceous aerosol mass is emitted from biomass combustion and the major fraction of these emissions is generated during smoldering combustion.
While hundreds of biomass-burning compounds have been identified at the molecular level, the chemical, physical, and toxic nature of the bulk of these biomass burning OC emissions remains poorly understood. To understand the impact of these atmospheric organics on the environment and human health, it is essential to know their chemical nature. In the present study, gas- and particle-phase biomass-burning emissions from different types of biomass fuels, mainly peats, were quantitatively and qualitatively analyzed for their chemical composition. The fuels were burned under controlled conditions (e.g., relative humidity, dilution of emissions, fuel-moisture content) at a biomass-burning facility (Reno, NV, USA). Fresh biomass-burning emissions were aged in an oxidation flow reactor (Aerodyne Research Inc.), mimicking several days of atmospheric aging. Samples were extracted from TIGF filters (particle-phase species) and XAD resin cartridges (gas-phase species) with dichloromethane followed by acetone and the resulting extracts were quantitatively analyzed for more than 200 organic compounds using gas chromatography mass spectrometry (GC/MS). Subsequently, the aliquots of these extracts were analyzed using the full-scan GC/MS technique to characterize unidentified organic species in fresh and OFR-aged biomass-burning emissions.