Amines have lower sooting tendencies than analogous alkanes, alcohols, and ethers
Section snippets
1. Introduction
Emissions of carbonaceous soot particles from combustion devices adversely impact human health and global warming. Ambient particulate matter, of which soot constitutes at least 10% [1,2], is one of the most important causes of reduced global life expectancy, leading to over 3 million deaths worldwide each year [3]. Recent calculations also conclude that soot is a major contributor to global warming, second only to CO2 [4]. As a result, many governments around the world have imposed particulate
2. Methods
In this work, the sooting tendencies of NHCs were quantified by doping a small amount of the test fuel into a nitrogen-diluted methane coflow flame, measuring the luminous signal due to soot, and linearly re-scaling the signal to YSI values [41,42].
3. Results
The aim of this study was to characterize the sooting tendencies of isomeric C4 and C6 amines. We begin by providing evidence that validates the YSI diagnostic in flames doped with NHCs, and then we present the measured YSIs for the amines.
4. Conclusion
In this work, the YSIs of 14 alkyl amines were determined. It was found that line-of-sight spectral radiance is a suitable technique for measuring sooting tendencies of nitrogen-containing hydrocarbons, with negligible error introduced due to the presence of nitrogen in the test compound. The YSIs of amines on the whole were found to be lower than structurally analogous hydrocarbons and oxygenates. Secondary amines with linear alkyl substituents were observed to have the lowest sooting
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
This material is based upon work supported by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Bioenergy Technologies Office (BETO) and Vehicle Technologies Office (VTO) Program Award Number DE-EE0007983. This work is also supported by the National Science Foundation (NSF) under Grant Number CBET 1604983. The XPS and XRF experiments were performed at the Yale West Campus Materials Characterization Core, using the PHI VersaProbe II X-ray
List of electronic supplemental information (ESI) materials
ESI A: A detailed diagram depicting the burner geometry used for the sooting tendency measurements
ESI B: Details on the compounds used in the soot blackness measurements.
ESI C: Details on amines and other nitrogen-containing hydrocarbons used in this study.
ESI D: Maximum LSSR Signal (relative to the undoped flame) from pyridine- and benzophenoneimine-doped flames versus concentration of dopant.
ESI E: LSSR Signal (relative to the average of the undoped flame) from undoped, toluene, and
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