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.
Resources
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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