Size-resolved Physicochemical Properties of Biomass Burning Aerosol
EMSL Project ID
60995
Abstract
Biomass burning aerosol (BBA) is a major component of atmospheric aerosols and plays critical roles in the climate. BBA can affect climate directly by absorbing and scattering light, causing overall warming or cooling effects. Moreover, BBA can indirectly affect climate by acting as seed for warm and cold cloud formation. Due to the limited understanding of physicochemical properties of BBA, predicted climate effects of BBA contain large uncertainties. In this study, we aim to improve the current uncertainties in the climate models related to fundamental understanding of physiochemical properties. The specific aims of this study include: 1) characterize the size-resolved physicochemical properties of BBA; and 2) investigate the dependence of physicochemical properties of BBA on combustion temperature.
We will perform controlled biomass combustion experiments with EMSL’s new capability, controlled combustion system. We will use wheatgrass as fuel. The controlled combustion experiments will be performed with an air-to-fuel ratio equal to 25 at combustion temperatures of 200, 400, 600, 800, or 1000 °C, representing the temperature range of BB from smoldering and early stages of flaming combustion. We will use a scanning mobility particle sizer (SMPS, TSI) to measure BBA electrical mobility size distribution, two Photoacoustic Extinctiometer will be used to measure the absorption and scattering coefficients at 405 and 870 nm, and 7-wavelength (370, 470, 520, 590, 660, 880, and 950 nm) Aethalometer (AE33, Aerosol Magee Scientific) will be utilized to provide light absorption coefficients at additional wavelengths. In addition, a long-time-of-flight aerosol mass spectrometer (L-tof-AMS) will be used to measure the real-time chemical composition of BBA. By comparing the size distribution, optical properties, and chemical composition of BBA generated from different combustion temperatures, we can have a comprehensive picture of BBA’s properties related to different combustion conditions.
For each experiment, we will collect BBA samples for offline measurements such as time-of-flight secondary ion mass spectrometry (ToF-SIMS) to probe BBA's detailed chemical composition, phase state, and mixing state. Nanospray desorption electrospray ionization (nano-DESI) high-resolution mass spectrometry (HRMS) will analyze PTFE filter samples to provide high-resolution molecular-level information. The volatile and semi-volatile organic species will be collected using sorbent tubes to study chemically-specific VOCs using a high-resolution TD Q-ToF GC/MS at EMSL.
Project Details
Project type
Exploratory Research
Start Date
2024-01-01
End Date
N/A
Status
Active
Released Data Link
Team
Principal Investigator
Team Members