ASTM D4294 - Sulfur in Petroleum and Petroleum Products by Energy Dispersive X-ray Fluorescence Spectrometry
Signiﬁcance and Use
5.1 This test method provides rapid and precise measure-ment of total sulfur in petroleum and petroleum products with a minimum of sample preparation. A typical analysis time is 1 min to 5 min per sample.
5.2 The quality of many petroleum products is related to the amount of sulfur present. Knowledge of sulfur concentration is necessary for processing purposes. There are also regulations promulgated in federal, state, and local agencies that restrict the amount of sulfur present in some fuels.
5.3 This test method provides a means of determining whether the sulfur content of petroleum or a petroleum product meets speciﬁcation or regulatory limits.
5.4 When this test method is applied to petroleum materials with matrices signiﬁcantly different from the calibration mate-rials speciﬁed in 10.1, the cautions and recommendations in Section 6 should be observed when interpreting results.
1.1 This test method covers the determination of total sulfur in petroleum and petroleum products that are single-phase and either liquid at ambient conditions, liqueﬁable with moderate heat, or soluble in hydrocarbon solvents. These materials can include diesel fuel, jet fuel, kerosine, other distillate oil, naphtha, residual oil, lubricating base oil, hydraulic oil, crude oil, unleaded gasoline, gasoline-ethanol blends, biodiesel (see Note 2), and similar petroleum products.
NOTE 1—Oxygenated fuels with ethanol or methanol contents exceed-ing the limits given in Table 1 can be dealt with using this test method, but the precision and bias statements do not apply (see Appendix X3).
NOTE 2—For samples with high oxygen contents (>3 % by weight) sample dilution as described in 1.3 or matrix matching must be performed to assure accurate results.
1.2 Interlaboratory studies on precision revealed the scope to be 17 mg ⁄kg to 4.6 % by mass. An estimate of this test method’s pooled limit of quantitation (PLOQ) is 16.0 mg ⁄kg as calculated by the procedures in Practice D6259. However, because instrumentation covered by this test method can vary in sensitivity, the applicability of the test method at sulfur concentrations below approximately 20 mg/kg must be deter-mined on an individual basis. An estimate of the limit of detection is three times the reproducibility standard deviation, and an estimate of the limit of quantitation2 is ten times the reproducibility standard deviation.
1.3 Samples containing more than 4.6 % by mass sulfur can be diluted to bring the sulfur concentration of the diluted material within the scope of this test method. Samples that are diluted can have higher errors than indicated in Section 17 than non-diluted samples.
1.4 Volatile samples (such as high vapor pressure gasolines or light hydrocarbons) may not meet the stated precision because of selective loss of light materials during the analysis.
Extracted, with permission, from ASTM D4294-21 - Sulfur in Petroleum and Petroleum Products by Energy Dispersive X-ray Fluorescence Spectrometry, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, astm.org