The role of fuel chemistry in dictating nanostructure evolution of soot toward source identification

Abstract

Laser derivatization is proposed as a diagnostic technique toward identifying the sources contributing to combustion produced soot. Fuel chemistry and the resultant oxygen content in nascent soot have been shown to influence the evolution of soot nanostructure upon laser derivatization. This is illustrated using the spectroscopic and microscopic characterization of biodiesel soot, with a systematic variation in fuel chemistry used to generate the soot. Functionalized carbon black is used as the control to independently verify the influence of material chemistry on nanostructure upon laser heat treatment. Results track with those observed for biodiesel soot. Reciprocally, the similarity in soot nanostructure observed after laser heating is tied to the likeness in fuel chemistry of biomass-fueled sources. Understanding the origin of differences or similarities in soot nanostructure upon laser heat treatment can help differentiate sources based on their contribution, thereby aiding in effective air quality control.

Copyright © 2019 American Association for Aerosol Research

EDITOR:

• Mark Swihart

Acknowledgments

Carbon black was provided by Cabot Corp. Biodiesel soot samples were provided by Dr. Andrea Strzelec (U. Wisconsin-Madison, College of Engineering), generated at the National Transportation Research Center c/o Oakridge National Labs, while soots from biomass sources were provided by Dr. Michael D. Hays, c/o The U.S. EPA, National Risk Management Research Laboratory. Material characterizations were performed using the facilities of the Materials Research Institute at the Pennsylvania State University.

Additional information

Funding

The authors acknowledge support by the National Science Foundation (NSF), Chemical, Bioengineering, Environmental, and Transport Systems (CBET), under Grant Number 1236757.