【国外标准】 Standard Test Method for Determination of Contamination Level of Fatty Acid Methyl Esters in Middle Distillate and Residual Fuels Using Flow Analysis by Fourier Transform Infrared Spectroscopy—Rapid Screening Method

5.1 The present and growing international governmental requirements to add Fatty Acid Methyl Esters (FAME) to diesel fuel has had the unintended side-effect of leading to potential FAME contamination of fuels in multi-fuel transport facilities such as cargo tankers and pipelines, and industry wide concerns. This has led to a requirement to measure contamination levels in diesel and other fuels to assist custody transfer issues.5.2 Analytical methods have been developed with the capability of measuring down to <5 mg/kg levels of FAME in aviation turbine fuel (AVTUR), however these are complex, and require specialized personnel and laboratory facilities. This Rapid Screening method has been developed for use in the supply chain by non-specialized personnel to cover the range of 20 mg/kg to 500 000 mg/kg (0.002 % to 50 %).5.3 A similar procedure, Test Method D7797, is available for AVTUR in the range 10 mg/kg to 150 mg/kg. Test Method D7797 uses the same apparatus, with a specific model developed for AVTUR.1.1 This test method specifies a rapid screening method using flow analysis by Fourier Transform Infrared (FA-FTIR) spectroscopy with partial least squares (PLS) processing for the quantitative determination of the fatty acid methyl ester (FAME) contamination of middle distillates, in the range of 20 mg/kg to 1000 mg/kg, and of middle distillates and residual fuels, following dilution, for levels above 0.1 %.NOTE 1: Annex A2 describes a dilution procedure to significantly expand the measurement range above 1000 mg/kg for distillates and to enable measurement of residual oilsNOTE 2: This test method detects all FAME components, with peak IR absorbance at approximately 1749 cm-1 and C8 to C22 molecules, as specified in standards such as D6751 and EN 14214. The accuracy of the test method is based on the molecular mass of C16 to C18 FAME species; the presence of other FAME species with different molecular masses could affect the accuracy.NOTE 3: Additives such as antistatic agents, antioxidants, and corrosion inhibitors are measured with the FAME by the FTIR spectrometer. However any potential interference effects of these additives are eliminated by the flow analysis processing.NOTE 4: The scope of this test method does not include aviation turbine fuel which is addressed by Test Method D7797.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.1.4 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.