ASTM D8368-22a

SIGNIFICANCE AND USE 5.1 The determination of group type composition of diesel fuel is useful for evaluating quality and expected performance. Aromatics and polyaromatics, in particular, are related to combustion characteristics, cetane number, energy content, lubricity, water solubility and exhaust emissions. 5.1.1 Aromatic hydrocarbon type analysis may be useful for evaluating refinery processes. 5.1.2 The ability to determine aromatics content in the presence of FAME may be useful to users of diesel fuel. SCOPE 1.1 This test method covers a standard procedure for the determination of group type totals of aromatic, polyaromatic, and FAME content in diesel fuel using gas chromatography and vacuum ultraviolet absorption spectroscopy detection (GC-VUV). 1.1.1 Polyaromatic totals are the result of the summation of diaromatic and tri-plus aromatic group types. Aromatics are the summation of monoaromatic and polyaromatic group types. FAME content is the result of summation of individual fatty acid methyl esters. 1.1.2 This test method is applicable for renewable diesel fuels from hydrotreated vegetable oil (HVO) or animal fat, gas to liquid (GTL) diesel, light cycle oil, wide boiling range aromatic solvents and biodiesel blends. 1.2 Concentrations of group type totals are determined by percent mass or percent volume. The applicable working ranges are as follows: Total Aromatics %Volume 0.088 to 77.000 Total Aromatics %Mass 0.104 to 79.451 MonoAromatics %Mass 0.076 to 67.848 Diaromatics %Mass 0.027 to 34.812 Tri-plus aromatics %Mass 0.45 to 6.77 PAH %Mass 0.028 to 41.586 FAME %Volume 1.08 to 21.67 1.3 Diesel fuel containing biodiesel, (FAME, that is, fatty acid methyl esters including soy methyl esters, rapeseed methylesters, tallow methylesters and canola methylesters) can be analyzed by this test method. The FAME component completely elutes from the analytical column independent of feedstock. 1.4 Individual hydrocarbon components are not reported by this test method; however, any individual component determinations are included in the appropriate summation of the totals of aromatic, polyaromatic, monoaromatic, diaromatic, tri-plus aromatic, or FAME groups. 1.4.1 Individual components are typically not baseline-separated by the procedure described in this test method. The coelutions are resolved at the detector using VUV absorbance spectra and deconvolution algorithms. 1.5 This test method may apply to other hydrocarbon streams boiling between heptane (98 °C) and triacontane (450 °C), but has not been extensively tested for such applications. 1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.7 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. 1.8 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.