Analysis of red dye in unburned and combusted diesel fuel

CHED 194

Jamie L. Virginia, jvirginia@ups.edu, Department of Chemistry, University of Puget Sound, 3819 WSC, Tacoma, WA 98416
Red dye is used as a regulatory dye in off-road diesel fuel in a standard concentration of 11.1mg/L. On-road fuel is taxed while off-road fuel is tax-exempt so the dye is used to differentiate between the two. This dye, if successful in surviving combustion, can be used to differentiate between soot from on-road emissions and off-road emissions in ambient air. This project focused on discovering whether the dye could survive combustion and, therefore, be used to look at ratios of on-road soot to off-road soot in large cities. After many attempts to locate the dye in soot samples run through various analytical instruments, it was concluded that the dye does not survive combustion.