Significance and Use
5.1 The determination of class group composition of automotive spark-ignition fuels as well as quantification of various individual species such as oxygenates and aromatics in automotive fuels is useful for evaluating quality and expected performance, as well as compliance with various governmental regulations.
Scope
1.1 This test method is a standard procedure for the determination in percent mass or percent volume of hydrocarbon group types (paraffins, isoparaffins, olefins, naphthenes, aromatics), methanol, ethanol, benzene, toluene, ethylbenzene, xylenes, naphthalene, and methylnaphthalenes in automotive spark-ignition engine fuels using gas chromatography and vacuum ultraviolet detection (GC-VUV).
1.1.1 The concentration ranges for which precision has been determined are as follows:
Property
Units
Applicable Range
Paraffins
% Volume
3.572 to 23.105
Isoparaffins
% Volume
22.697 to 71.993
Olefins
% Volume
0.011 to 44.002
Olefins
% Mass
0.027 to 41.954
Naphthenes
% Volume
0.606 to 18.416
Aromatics
% Volume
14.743 to 58.124
Methanol
% Volume
0.063 to 3.426
Ethanol
% Mass
0.042 to 15.991
Benzene
% Volume
0.09 to 1.091
Toluene
% Volume
0.698 to 31.377
Ethylbenzene
% Volume
0.5 to 3.175
Xylenes
% Volume
3.037 to 18.955
Naphthalene
% Volume
0.019 to 0.779
Methylnaphthalenes
% Volume
0.21 to 1.484
1.1.2 This test method may be applicable to other concentration ranges, to other properties, or to other hydrocarbon streams, however precision has not been determined.
1.2 Individual hydrocarbon components are typically not baseline-separated by the procedure described in this test method, that is, some components will coelute. The coelutions are resolved at the detector using VUV absorbance spectra and deconvolution algorithms.
1.3 While this test method reports percent mass and percent volume for several specific components that may be present in automotive spark-ignition engine fuel, it does not attempt to speciate all possible components that may occur in automotive spark-ignition engine fuel. In particular, this test method is not intended as a type of detailed hydrocarbon analysis (DHA).
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See specific hazard statements in subsection 8.4 and Section 9.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
