1、Designation: D7039 13Standard Test Method forSulfur in Gasoline, Diesel Fuel, Jet Fuel, Kerosine,Biodiesel, Biodiesel Blends, and Gasoline-Ethanol Blendsby Monochromatic Wavelength Dispersive X-rayFluorescence Spectrometry1This standard is issued under the fixed designation D7039; the number immedia
2、tely following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This t
3、est method covers the determination of total sulfurby monochromatic wavelength-dispersive X-ray fluorescence(MWDXRF) spectrometry in single-phase gasoline, diesel fuel,refinery process streams used to blend gasoline and diesel, jetfuel, kerosine, biodiesel, biodiesel blends, and gasoline-ethanolblen
4、ds.NOTE 1Volatile samples such as high-vapor-pressure gasolines orlight hydrocarbons might not meet the stated precision because of theevaporation of light components during the analysis.1.2 The range of this test method is between the pooled limitof quantitation (PLOQ) value (calculated by procedur
5、es con-sistent with Practice D6259) of 3.2 mg/kg total sulfur and thehighest level sample in the round robin, 2822 mg/kg totalsulfur.1.3 Samples containing oxygenates can be analyzed withthis test method provided the matrix of the calibration stan-dards is either matched to the sample matrices or th
6、e matrixcorrection described in Section 5 or Annex A1 is applied to theresults. The conditions for matrix matching and matrix correc-tion are provided in the Interferences section (Section 5).1.4 Samples with sulfur content above 2822 mg/kg can beanalyzed after dilution with appropriate solvent (see
7、 5.4). Theprecision and bias of sulfur determinations on diluted sampleshas not been determined and may not be the same as shown forneat samples (Section 15).1.5 When the elemental composition of the samples differsignificantly from the calibration standards used to prepare thecalibration curve, the
8、 cautions and recommendation in Section5 should be carefully observed.1.6 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
9、 It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardinformation, see 3.1.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling o
10、f Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6259 Practice for Determination of a Pooled Limit ofQuantitationD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System
11、PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricants2.2 EPA Documents:340 CFR 80.584 Code of Federal Regulations; Title 40; Part80; U.S. Environmental Agency, July 1, 20053. Summary of Test Method3.1 A monochromatic X-ray
12、beam with a wavelength suit-able to excite the K-shell electrons of sulfur is focused onto atest specimen contained in a sample cell (see Fig. 1). Thefluorescent K radiation at 0.5373 nm (5.373 ) emitted by1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid
13、 Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved Sept. 15, 2013. Published October 2013. Originallyapproved in 2004. Last previous edition approved in 2007 as D7039 07. DOI:10.1520/D7039-13.2For referenced ASTM standards, vi
14、sit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from U.S. Government Printing Office, 732 N. Capitol Street, NW,Washington, DC 20401
15、.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1sulfur is collected by a fixed monochromator (analyzer). Theintensity (counts per second) of the sulfur X rays is measur
16、edusing a suitable detector and converted to the concentration ofsulfur (mg/kg) in a test specimen using a calibration equation.Excitation by monochromatic X rays reduces background,simplifies matrix correction, and increases the signal/background ratio compared to polychromatic excitation used inco
17、nventional WDXRF techniques.4(WarningExposure toexcessive quantities of X-ray radiation is injurious to health.The operator needs to take appropriate actions to avoidexposing any part of his/her body, not only to primary X rays,but also to secondary or scattered radiation that might bepresent. The X
18、-ray spectrometer should be operated in accor-dance with the regulations governing the use of ionizingradiation.)4. Significance and Use4.1 This test method provides for the precise measurementof the total sulfur content of samples within the scope of thistest method with minimal sample preparation
19、and analystinvolvement. The typical time for each analysis is five minutes.4.2 Knowledge of the sulfur content of diesel fuels,gasolines, and refinery process streams used to blend gasolinesis important for process control as well as the prediction andcontrol of operational problems such as unit cor
20、rosion andcatalyst poisoning, and in the blending of products to com-modity specifications.4.3 Various federal, state, and local agencies regulate thesulfur content of some petroleum products, including gasolineand diesel fuel. Unbiased and precise determination of sulfur inthese products is critica
21、l to compliance with regulatory stan-dards.5. Interferences5.1 Differences between the elemental composition of testsamples and the calibration standards can result in biased sulfurdeterminations. For samples within the scope of this testmethod, elements contributing to bias resulting from differ-en
22、ces in the matrices of calibrants and test samples arehydrogen, carbon, and oxygen. A matrix-correction factor (C)can be used to correct this bias; the calculation is described inAnnex A1. For general analytical purposes, the matrices of testsamples and the calibrants are considered to be matched wh
23、enthe calculated correction factor C is within 0.98 to 1.04. Nomatrix correction is required within this range. A matrixcorrection is required when the value of C is outside the rangeof 0.98 to 1.04. For most testing, matrix correction can beavoided with a proper choice of calibrants. For example, b
24、asedon the example graph in AnnexA1 (Fig. 2), a calibrant with 86mass % carbon and 14 mass % hydrogen can cover non-oxygencontaining samples with C/H ratios from 5.4 to 8.5. Forgasolines with oxygenates, up to 2.3 mass % oxygen (12 mass% MTBE) can be tolerated for test samples with the same C/Hratio
25、 as the calibrants.5.2 Fuels containing large quantities of oxygenates, such asbiodiesel, biodiesel blends, and gasoline-ethanol blends, canhave a high oxygen content leading to significant absorption ofsulfur K radiation and low sulfur results.5.2.1 Biodiesel and biodiesel blends may be analyzed us
26、ingthis test method by applying correction factors to the results orusing calibration standards that are matrix-matched to the testsample (see Table 1). Correction factors may be calculated (seeAnnex A1), or obtained from Table 2 if the sample has beenmeasured on a mineral oil calibration curve.5.2.
27、2 Gasoline-ethanol blends may be analyzed using thistest method by applying correction factors to the results orusing calibration standards that are matrix matched to the testsample (see Table 1). Correction factors may be calculated (seeAnnex A1), or obtained from the correction tables. Use Table3
28、if the sample has been measured on a mineral oil calibrationcurve, or use Table 4 if the sample has been measured on anethanol calibration curve. Ethanol-based calibrants can be usedfor gasoline-ethanol blends. Ethanol-based calibrants are rec-ommended for gasoline-ethanol blends containing more tha
29、n50 % (by volume) ethanol.4Bertin, E. P., Principles and Practices of X-ray Spectrometric Analysis ,Plenum Press, New York, 1975, pp. 115-118.FIG. 1 Schematic of the MWDXRF AnalyzerD7039 1325.3 Other samples having interferences as described in 5.1may be analyzed using this test method by applying c
30、orrectionfactors to the results or by using calibration standards that arematrix matched to the test sample (see Table 1). Correctionfactors may be calculated as described in Annex A1.5.4 To minimize any bias in the results, use calibrationstandards prepared from sulfur-free base materials of the sa
31、meor similar elemental composition as the test samples. Whendiluting samples, use a diluent with an elemental compositionthe same or similar to the base material used for preparing thecalibration standards.5.4.1 A base material for gasoline can be approximatelysimulated by mixing 2,2,4-trimethylpent
32、ane (isooctane) andtoluene in a ratio that approximates the expected aromaticcontent of the samples to be analyzed.6. Apparatus6.1 Monochromatic Wavelength Dispersive X-ray Fluores-cence (MWDXRF) Spectrometer5, equipped for X-ray detec-tion at 0.5373 nm (5.373). Any spectrometer of this type canbe u
33、sed if it includes the following features, and the precisionand bias of test results are in accordance with the valuesdescribed in Section 15.6.1.1 X-ray Source, capable of producing X rays to excitesulfur. X-ray tubes with a power 25W capable of producingRh L,PdL,AgL,TiK,ScK, and Cr K radiation are
34、recommended for this purpose.6.1.2 Incident-beam Monochromator, capable of focusingand selecting a single wavelength of characteristic X rays fromthe source onto the specimen.6.1.3 Optical Path, designed to minimize the absorptionalong the path of the excitation and fluorescent beams using avacuum o
35、r a helium atmosphere. A vacuum of 2.7 kPa (20Torr) is recommended. The calibration and test measurementsmust be done with identical optical paths, including vacuum orhelium pressure.5The sole source of this apparatus known to the committee at this time is X-rayOptical Systems, Inc., 15 Tech Valley
36、Drive, East Greenbush, NY 12061. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee, which you may attend.FIG. 2 Matrix Correction for a Tes
37、t Sample vs. C/H and Total Oxygen Content Using Chromium K for the Excitation BeamTABLE 1 Methods for Interference Correction by Sample TypeSample TypeCorrectionTables (Table2, Table 3,Table 4,orN/A)CorrectionCalculation(Annex A1)MatrixMatchingBiodiesel and Biodiesel Blends 2 Yes YesGasoline-ethanol
38、 Blends 3 or 4 Yes YesAll Other Sample Types N/A Yes YesD7039 1336.1.4 Fixed-channel Monochromator, suitable for dispersingsulfur K X rays.6.1.5 Detector, designed for efficient detection of sulfur KX rays.6.1.6 Single-Channel Analyzer, an energy discriminator tomonitor only sulfur radiation.6.1.7 R
39、emovable Sample Cell, an open-ended specimenholder compatible with the geometry of the MWDXRF spec-trometer and designed to use replaceable X-ray transparent film(see 6.1.8) to hold a liquid specimen with a minimum depth of5mm. The sample cell must not leak when fitted with X-raytransparent film. A
40、disposable cell is recommended.6.1.8 X-Ray Transparent Film, for containing and support-ing the test specimen in the sample cell (see 6.1.7) whileproviding a low-absorption window for X rays to pass to andfrom the sample. Any film resistant to chemical attack by thesample, free of sulfur, and X-ray
41、transparent can be used, forexample, polyester, polypropylene, polycarbonate, and poly-imide. However, samples of high aromatic content can dissolvepolyester and polycarbonate films.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise ind
42、icated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.6Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its
43、 use without lessening the accuracy ofthe determination.7.2 Calibration-Check Samples, for verifying the accuracyof a calibration. The check samples shall have known sulfurcontent and not be used in determining the calibration curve. Astandard from the same reliable and consistent source of6Reagent
44、Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, D.C. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand Na
45、tional Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.TABLE 2 Correction Factors for Biodiesel Blends Measured on a Mineral Oil Calibration CurveNOTE 1Determine the correction factor in the table below by finding the known oxygen content of the test specimen (for example, 11 wt
46、 %) as thesum of the value in the first column and the value in the first row (for example, 11 = 10+1). The intersection of these two values is the correction factor(for example, 1.1914). Apply the correction according to 12.5.Oxygen, wt % 0 % 1 % 2 % 3 % 4 % 5 % 6 % 7 % 8 % 9 %0 % 1.0000 1.0174 1.0
47、348 1.0522 1.0696 1.0870 1.1044 1.1218 1.1392 1.156610 % 1.1740 1.1914 1.2088 1.2262 1.2436 1.2610 1.2784 1.2958 1.3132 1.3306TABLE 3 Correction Factors for Gasoline-ethanol Blends Measured on a Mineral Oil Calibration CurveNOTE 1Determine the correction factor in the table below by finding the know
48、n ethanol content of the test specimen (for example, 15 vol %) as thesum of the value in the first column and the value in the first row (for example, 15 = 10+5). The intersection of these two values is the correction factor(for example, 1.0881). Apply the correction according to 12.5.Ethanol, vol %
49、 0 % 1 % 2 % 3 % 4 % 5 % 6 % 7 % 8 % 9 %0 % 0.9895 0.9962 1.0029 1.0095 1.0161 1.0228 1.0294 1.0360 1.0425 1.049110 % 1.0556 1.0621 1.0686 1.0751 1.0816 1.0881 1.0945 1.1009 1.1073 1.113720 % 1.1201 1.1265 1.1328 1.1391 1.1455 1.1518 1.1580 1.1643 1.1706 1.176830 % 1.1830 1.1892 1.1954 1.2016 1.2077 1.2139 1.2200 1.2261 1.2322 1.238340 % 1.2444 1.2504 1.2565 1.2625 1.2685 1.2745 1.2805 1.2865 1.2924 1.298450 % 1.3043 1.3102 1.3161 1.3220 1.3279 1.3337 1.3396 1.3454 1.3512 1.357060 % 1.3628 1.3686 1.3743 1.3801 1.3858 1.3915 1.3972 1.4029 1.4086 1.414370 % 1.4199
