Researchers from The US Naval Research Laboratory, National Research Council, the University of Pennsylvania and Nova Research are proposing a new automated method to characterize the distribution of hydrocarbons in transportation fuels.
The characterization of hydrocarbon fuels (middle-distillates) has been a challenging task for decades due to the striking complexity of the samples. It has been proposed that diesel fuels may contain more than 100,000 distinct chemical components.
...Determination of the distribution and types of hydrocarbons present in a given fuel is a necessary prerequisite for determining the Fit-For-Purpose (FFP) of a fuel for its intended use. This is of particular importance as the fuel user community is faced with the task of certifying fuels derived from alternative nonpetroleum sources. In most instances, while many of these alternative fuels are suitable for use as a replacement for their petroleum-derived counterparts, their constituency can be distinctly different from the traditional petroleum-derived fuels that they are intended to replace. Thus, an understanding of the chemical constituency of these fuels is critical for certification and quality surveillance.—Begue et al.
Their proposed method, presented in a paper in the ACS journal Energy & Fuels, uses a novel classification algorithm based on a text parser that operates on the chemical name or formula from a previously generated “hit list”. They validated their method against synthetically generated data and a DHA PIANO (detailed hydrocarbon analysis paraffins, iso-paraffins, aromatics, napthenes and olefins) blend standard.
The method described here has been developed and tested for the characterization of hydrocarbon content type in fuels, but is applicable to the automated analysis of any complex mixture such as extracts of soils or whole air samples. While not suggested as a replacement for more detailed analyses, such as the ASTM methods, the profiler requires no sample preparation or analyst intervention, thus making this an attractive method for initial studies or studies of exceptionally large sample libraries. Also the fuel profiles generated here are much more detailed in that the compounds observed for each hydrocarbon class are also reported. The primary limitation of the technique is that profile outputs are presented in area percent and not mass percent.—Begue et al.
Nathan J. Begue, Jeffery A. Cramer, Chris Von Bargen, Kristina M. Myers, Kevin J. Johnson, Robert E. Morris (2011) Automated Method for Determining Hydrocarbon Distributions in Mobility Fuels. Energy & Fuels doi: /10.1021/ef101635a