Functional group analysis of organic particulate matter from primary and aged biomass burning emissions in the FORTH environmental chamber with infrared spectroscopy

Biomass burning from residential wood burning, wildfires, and prescribed burning is a major source of organic matter (OM). Aerosol mass spectrometry (AMS) and Fourier transform infrared spectroscopy (FT-IR) are common methods of characterizing OM. AMS possesses a high temporal resolution and FT-IR, carried out mostly on PTFE filters, provides detailed functional group information. We utilized AMS and FT-IR to investigate the effects of aging on the chemical composition and concentration of OM from wood and pellet burning. Primary emissions were injected into the an environmental and aged using UV light or the nitrate radical (in high- and low-humidity conditions) to simulate day-time and night-time oxidation processes in the atmosphere. Estimates of OM from AMS and FT-IR agree well, both detecting an increased O:C after aging. Mid-infrared spectroscopy, shows distinct functional group compositions (hence oxidation pathways) for aged biomass burning aerosols with UV light and in dark conditions.