1.1 本试验方法包括分离和测定沸点在170℃之间的中间馏分中的代表性芳烃、非芳烃和脂肪酸甲酯（FAME）馏分 °C和400 °C，包括最高20 % 通过固相萃取和气相色谱法测定FAME的体积。 1.2 本试验方法提供了两个程序，A和B。程序A适用于石油基中间馏分燃料，程序B适用于含有20 % 以FAME的体积计。 1.3 本试验方法适用于芳烃含量在5 % 至50 % FAME含量在0.5范围内的生物柴油混合物 % 至20 % 按体积计算。该试验方法可适用于这些范围以外的浓度，但精度尚未确定。 1.4 对于程序B，脂肪酸乙酯（FAEE）形式的生物柴油也可以完全洗脱到FAME馏分中，并且它们具有与FAME相似的FID（火焰离子化检测器）相对响应因子。FAME级分的测定含量是通过该试验方法测定的FAME和FAEE浓度之和（见 3.2.5 ). 1.5 根据FAME测定的调查结果，低浓度的单甘油酯（通常小于0.5 % 在本试验方法的气相色谱（GC）条件下检测不到生物柴油混合物（以质量计），且不会干扰程序B中FAME的测定。因此，符合规范要求的生物柴油混合物 D7467型 ，最多包含20个 % 符合规范要求的生物柴油混合料体积 D6751型 ，通常含有小于0.1 % 在本试验方法的GC条件下，由于其沸点较高，因此未检测到甘油二酯和甘油三酯（如果存在）。 注1: 如果怀疑样品中含有不符合规范规定的FAME生物柴油原料 D6751型 例如，被总甘油三酯含量高的植物油污染的样品，可使用试验方法测定分离的FAME馏分中的单、二或三甘油酯含量 D6584型 .含有甘油含量高于规范规定的生物柴油的样品 D6751型 可能会污染GC柱，不建议用于此测试方法。 1.6 以可接受的SI单位表示的值应视为标准。 本标准不包括其他测量单位 1.7 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 对于沸点范围在170之间的中间馏分 °C和400 通过试验方法等蒸馏方法 887年 ，程序A可通过SPE和GC分析所得馏分，分离并测定总芳烃和总非芳烃的含量。测定石油中间馏分中饱和烃和芳烃的总含量有助于研究石油工艺对各种成品燃料生产的影响。 5.2 总芳烃含量和多环芳烃含量是表征柴油质量的重要指标。通过减少试剂消耗量和避免溶剂蒸发步骤的必要性，例如在该试验方法中，该试验方法被证明是省时和环保的 第2549页 . 5.3 通过质谱法测定详细的碳氢化合物成分，需要将样品初步分离成具有代表性的芳香族化合物和非芳香族化合物，如试验方法 第2425页 ，其中测试方法 第2549页 用于分离馏出燃料。本文所述的SPE分馏程序可为这些质谱类型的方法提供合适的分馏替代方法。 5.4 生物柴油是一种混合原料商品，主要用作柴油燃料的增值混合组分。程序B可提供分离和测定技术，以监测FAME生物柴油混合物的FAME含量。

1.1 This test method covers the separation and determination of representative aromatics, nonaromatics, and fatty acid methyl ester (FAME) fractions in middle distillates that boil between 170 °C and 400 °C, including biodiesel blends with up to 20 % by volume of FAME, by solid phase extraction and gas chromatography. 1.2 This test method provides two procedures, A and B. Procedure A is applicable to the petroleum-based middle distillates fuel, and Procedure B is applicable to the biodiesel blends with up to 20 % by volume of FAME. 1.3 This test method is applicable to middle distillates samples with aromatics content ranging from 5 % to 50 % by mass and biodiesel blends with FAME content in the range of 0.5 % to 20 % by volume. This test method may apply to concentrations outside these ranges, but the precision has not been determined. 1.4 For Procedure B, biodiesels in the form of fatty acid ethyl ester (FAEE) can also fully elute into the FAME fraction, and they have the similar FID (flame ionization detector) relative response factors with that of FAME. The determined content of FAME fractions are the sum of concentrations of FAME and FAEE by this test method (see 3.2.5 ). 1.5 From the investigation results obtained for FAME determination, the low concentrations of monoglycerides (usually less than 0.5 % by mass in biodiesel blends) are not detectable under the gas chromatographic (GC) condition of this test method and will not interfere with the determination of FAME by Procedure B. As a result, biodiesel blends, conforming to the requirements of Specification D7467 , containing up to 20 % by volume of biodiesel blendstock meeting the requirements in Specification D6751 , typically contain concentrations of monoglycerides of less than 0.1 % by mass. The diglycerides and triglycerides, if present, are not detected under the GC condition of this test method due to their higher boiling points. Note 1: If a sample is suspected of containing an abnormal FAME biodiesel feedstock than specified in Specification D6751 , for example, a sample contaminated with vegetable oil with a high level of total triglycerides, the content of mono-, di-, or tri-glycerides in the isolated FAME fraction may be determined using Test Method D6584 . Samples containing biodiesels with a high amount of glycerides than specified in Specification D6751 may contaminate the GC column and not recommended for this test method. 1.6 The values stated in acceptable SI units are to be regarded as the 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. ====== Significance And Use ====== 5.1 For the middle distillates whose boiling range is between 170 °C and 400 °C by such distillation methods like Test Method D2887 , Procedure A can separate and determine the content of total aromatics and total nonaromatics by SPE and GC analysis of the resulting fractions. The determination of the total content of saturates and aromatics in petroleum middle distillates is useful to investigate the effects of petroleum processes on production of various finished fuels. 5.2 The total aromatics content and polycyclic aromatics content are important to characterize the quality of diesel fuels. This test method is demonstrated to be time-saving and eco-friendly by reducing the amount of reagent consumption and avoiding the necessity of solvent evaporation step as required, for example, in such Test Method D2549 . 5.3 The determination of detailed hydrocarbon composition by mass spectrometry requires a preliminary separation of the sample into representative aromatics and nonaromatics, as in Test Method D2425 , where Test Method D2549 is used to separate the distillate fuel. The SPE fractionation procedure described herein may provide a suitable fractionation alternative approach for these mass spectrometric types of methods. 5.4 Biodiesel is a blendstock commodity primarily used as a value-added blending component with diesel fuel. Procedure B can provide a separation and determination technique to monitor the FAME content for FAME biodiesel blends.