Research Projects

Diesel engines are major contributions to the emission of toxic substances into the atmosphere. These toxic substances are a vital concern nationwide due to human health and environmental effects. For regulation of exhaust emissions and quality of fuel, improved methods of quantitation and characterization of problem-causing components of diesel fuel are needed.

This program was performed in response to the need for improved chemical analysis of aromatic content in diesel fuel. The analytical techniques used, infrared (IR) analysis and ultraviolet (W) spectroscopy, are familiar, convenient to run, and readily available. Both methods proved to be fairly rugged in terms of variety of fuels, treatments, and additives of tested materials. The effort included method optimization, correlation to FIA results, and statistical analysis of the quality of measurements possible with the methods.

Results of testing on a large data-base of samples and a round-robin study on the two methods in various laboratories showed repeatability of 0.6 VOL % and reproducibility of 1.7 VOL % in the range of 10% predicted aromatics for the infrared method; with a pooled repeatability of 0.2 WT % ring carbon and reproducibility of 0.8 WT% ring carbon for the W method for total WT% ring carbon. The W method also provides values for mono-, di- and tri-ring aromatic species. Both methods are relatively inexpensive and easy to run, and would be amenable to automation.