10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Effects of Thermodenuding on the Morphology and Optical Properties of Soot
NISHIT SHETTY, Apoorva Pandey, Yuli W. Heinson, Rajan K. Chakrabarty, Washington University in St. Louis
Abstract Number: 1577 Working Group: Carbonaceous Aerosol
Abstract Soot particles are composed of refractory elemental carbon and have varying amounts of condensed organic carbon coating. The optical properties of soot depend on the complex refractive indices and the effective size of the coated particles, as well as the particle morphology. A preferred methodology to investigate the change in optical properties of soot due to coating is to perform experiments with and without a thermodenuder. The conventional view is that the particle morphology doesn’t change upon thermodenuding; we investigate the validity of this assumption in this study.
We performed experiments to investigate the effect of coating on the optical properties of soot generated from biomass burning and kerosene lamp. The organic coating was removed using a thermodenuder (Brechtel inc.) and the resulting change in absorption and scattering coefficients was measured using an integrated photoacoustic-nephelometer. In a separate set of experiments, the aerosol was passed through an angle-resolved static light scattering apparatus which provides information on the morphology of particles using q-space analysis of the scattered light. We monitored the change in soot morphology as a function of burn parameters using this optical setup. This poster will outline our findings from these set of experiments.