Standard Test Method for Determination of Biodiesel and Hydrocarbon Types in Middle Distillate and Renewable Diesel Fuels by Supercritical Fluid Chromatography

Importancia y uso:

5.1 The aromatic hydrocarbon content of motor diesel fuels is a factor that can affect fuel performance, including their cetane number and exhaust emission.

5.2 The United States Environmental Protection Agency (USEPA) regulates the aromatic content of diesel fuels. California Air Resources Board (CARB) regulations place limits on the total aromatics content and polynuclear aromatic hydrocarbon content of motor diesel fuel, thus requiring an appropriate analytical determination to ensure compliance with the regulations. Producers of diesel fuels will require similar determinations for process and quality control. This test method can be used to make such determinations.

5.3 The United States Federal Government, in addition to state governments, offers an array of subsidies to reduce emissions caused by the consumption of fossil fuels. Therefore, the production and consumption of biofuels as an alternative fuel to fossil fuels are encouraged. Thus, an appropriate analytical method to determine the content of the biofuels blended with refined fossil fuels is needed. This test method is applicable to materials in the boiling range of middle distillates and higher boiling motor diesel fuels and can be used to determine the total FAME content of the blend as well as the total aromatic content.

5.4 Test Methods D1319, D5186, and D6591, which are used to determine the aromatic hydrocarbon content in middle distillates and higher boiling diesel fuels, report an artificially high aromatic content with fuels containing biodiesel. The higher than actual results are attributed to the biodiesel species coeluting with aromatic species. This test method is based on a group type separation with an additional silica column for backflushing the biodiesel to the detector to prevent the coelution of the two different group types.

5.5 This test method was developed with the higher boiling point of diesel fuels as the focal point, as it contains the highest number of aromatic rings. If lower boiling point middle distillate fuels are analyzed exclusively, then the chromatographic method can be established with markers similar to the fuels being analyzed.

Subcomité:

D02.04.0C

Volúmen:

05.05

Palabras clave:

aromatic hydrocarbons; aromatics; biodiesel; biofuel; diesel fuel; esters; FAME; methyl esters; monoaromatics; polynuclear; polynuclear aromatics; supercritical fluid chromatography;