ASTM D8071-2017 7675 Standard Test Method for Determination of Hydrocarbon Group Types and Select Hydrocarbon and Oxygenate Compounds in Automotive Spark-Ignition Engine Fuel Using.pdf

1、Designation: D8071 17Standard Test Method forDetermination of Hydrocarbon Group Types and SelectHydrocarbon and Oxygenate Compounds in AutomotiveSpark-Ignition Engine Fuel Using Gas Chromatography withVacuum Ultraviolet Absorption Spectroscopy Detection (GC-VUV)1This standard is issued under the fix

2、ed designation D8071; the number immediately 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 re

3、vision or reapproval.1. Scope1.1 This test method is a standard procedure for the deter-mination of paraffins, isoparaffins, olefins, naphthenes,aromatics, ethanol, and methanol in automotive spark-ignitionengine fuels using gas chromatography and vacuum ultravioletdetection (GC-VUV).1.2 Concentrati

4、ons of compound classes and certain indi-vidual compounds are determined by percent mass or percentvolume.1.2.1 The method is developed for testing automotive spark-ignition engine fuels having concentrations of approximately6 % to 17 % by mass paraffins, 24 % to 70 % by massisoparaffins, 0.1 % to 1

5、6 % by mass olefins, 1 % to 14 % bymass naphthenes, and 16 % to 58 % by mass aromatics.Pending confirmation by a full interlaboratory study, themethod is projected to be applicable to a wider range ofconcentrations and matrices. Temporary repeatability has beendetermined on a limited subset of sampl

6、es given in 17.1.1.3 Individual aromatic components and groups of aromat-ics greater than 0.01 % by mass are determined.1.3.1 The method is developed for testing automotive spark-ignition engine fuels having concentrations of 0.08 % to 2.2 %by mass benzene, 1.7 % to 15 % by mass toluene, 0.3 % to 3

7、%by mass ethylbenzene, 1.5 % to 17 % by mass total xylenes,0.06 % to 0.6 % by mass naphthalene, and 0.06 % to 1.1 % bymass total methylnaphthalenes. Pending confirmation by a fullinterlaboratory study, the method is projected to be applicableto a wider range of concentrations and matrices. Temporary

8、repeatability has been determined on a limited subset ofsamples given in Table 8.1.4 Isooctane (2,2,4-trimethylpentane) content is deter-mined in the range 0.1 % by mass to 22 % by mass.1.5 Ethanol and methanol may be determined by this testmethod. Ethanol is determined in the range of 0.1 % by mass

9、to 15.0 % by mass. Methanol is determined in the range of0.1 % by mass to 1.0 % by mass. Temporary repeatability hasbeen determined on a limited subset of samples containingethanol given in 17.1. Repeatability for methanol is currentlynot available.1.6 Individual hydrocarbon components are typically

10、 notbaseline-separated by the procedure described in this testmethod, that is, some components will coelute. The coelutionsare resolved at the detector using VUV absorbance spectra anddeconvolution algorithms.1.7 While this test method reports percent mass and percentvolume for several specific comp

11、onents that may be present inautomotive spark-ignition engine fuel, it does not attempt tospeciate all possible components that may occur in automotivespark-ignition engine fuel. In particular, this test method is notintended as a type of detailed hydrocarbon analysis (DHA).1.8 This test method has

12、been tested for spark-ignitionengine fuels; the method may apply to spark-ignition blendingstreams but has not been extensively tested for such applica-tions.1.9 UnitsThe values stated in SI units are to be regardedas standard. No other units of measurement are included in thisstandard.1.10 This sta

13、ndard does not purport to address all of thesafety concerns, if any, associated with its use. It is the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.04.0L on Gas Chromatography

14、Methods.Current edition approved March 1, 2017. Published March 2017. DOI: 10.1520/D8071-17.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized princip

15、les on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1responsibility of the user of this standard to establish appro-priate safety

16、and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD5842 Practice fo

17、r Sampling and Handling of Fuels forVolatility MeasurementD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Prod

18、ucts andLubricantsD6730 Test Method for Determination of Individual Com-ponents in Spark Ignition Engine Fuels by 100MetreCapillary (with Precolumn) High-Resolution Gas Chro-matographyD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing Laboratories3. Terminology3.1 Definiti

19、ons of Terms Specific to This Standard:3.1.1 integration filter, na mathematical operation per-formed on an absorbance spectrum for the purpose of convert-ing the spectrum to a single-valued response suitable forrepresentation in a two-dimensional chromatogram plot.3.1.2 library reference spectrum,

20、nan absorbance spec-trum representation of a molecular species stored in a librarydatabase and used for identification of a compound/compoundclass or deconvolution of multiple coeluting compounds.3.1.3 response area, ngenerally refers to a responsesummed over a given time interval and has units of a

21、bsorbanceunits (AU).3.1.3.1 DiscussionA time factor necessary to convert aresponse area to a true mathematical area cancels out of allcritical calculations and is omitted.3.2 Abbreviations:3.2.1 AUabsorbance units3.2.2 DHAdetailed hydrocarbon analysis3.2.3 GC-VUVgas chromatography with vacuum ultrav

22、io-let spectroscopy detection3.2.4 RIretention index3.2.5 RRFrelative response factor4. Summary of Test Method4.1 An automotive spark-ignition fuel sample is introducedto a gas chromatographic (GC) system. After volatilization, theeffluent is introduced onto a GC column for separation, andthen detec

23、ted by a vacuum ultraviolet absorption spectroscopydetector.3The separation is accomplished using a 30 m, non-polar phase capillary column and a moderately fast temperatureramp (typical operating parameters of this test method aregiven in Section 14). Coelutions are resolved by the detectorusing vac

24、uum ultraviolet absorbance spectra and deconvolu-tion.4.2 The result of the measurement is the determination ofthe total response areas of the five hydrocarbon classes ofparaffins, isoparaffins, olefins, naphthenes, and aromatics, inaddition to several individual species components. The percentmass

25、concentrations are calculated from the response areasusing class-based or compound-specific relative responsefactors, as appropriate.5. Significance and Use5.1 The determination of class group composition of auto-motive spark-ignition fuels as well as quantification of variousindividual species such

26、 as oxygenates and aromatics in auto-motive fuels is useful for evaluating quality and expectedperformance, as well as compliance with various governmentalregulations.6. Interferences6.1 Interferences with this test method, if any, have not beendetermined.7. Apparatus7.1 Gas chromatograph, equipped

27、with automated oventemperature control and split/splitless inlet.7.1.1 Preferably the gas chromatograph is equipped with anautosampler. This is not strictly necessary, but all statisticaldata were obtained using a GC equipped with an autosampler.7.1.2 Syringe, 0.5 uLvolume appropriate for injecting

28、liquidsamples.7.2 Carrier Gas, for gas chromatograph: nitrogen, helium,or hydrogen (see 8.2).7.3 Purge/Makeup Gas, for detector: nitrogen or argon (see8.3).7.4 Oxygen, Water, Hydrocarbon Filters, to further purifyGC carrier gas and detector purge/makeup gas.7.5 Capillary Analytical Column, nonpolar

29、(for example,dimethyl polysiloxane) phase, dimensions 30 m length,0.25 mm internal diameter, 0.25 m film thickness.7.6 Vacuum Ultraviolet Absorption Spectroscopy Detector,capable of measuring 125 nm to 240 nm absorbance spectrawith a wavelength resolution of 1 nm or better.7.6.1 The detector shall b

30、e able to interface with a gaschromatographic system and measure an eluent with a scanfrequency of at least 5 Hz with a baseline peak-to-peak noise2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandard

31、s volume information, refer to the standards Document Summary page onthe ASTM website.3The sole source of supply of the apparatus known to the committee at this timeis VUV-Analytics, Cedar Park, Texas. If you are aware of alternative suppliers,please provide this information to ASTM International He

32、adquarters. Your com-ments will receive careful consideration at a meeting of the responsible technicalcommittee,1which you may attend.D8071 172width over a 10 s interval no greater than 0.002 AU whenaveraged over the following wavelength regions: 125 nm to240 nm, 170 nm to 200 nm, 125 nm to 160 nm,

33、 and 0.001 AUwhen averaged over the 140 nm to 160 nm wavelength region.7.6.2 The detector shall be equipped with a shutter orequivalent mechanism that allows the detector array to beblocked from the light source in order to perform a “dark”measurement of electronic noise level.7.6.3 The detector sha

34、ll be equipped with a flow cell capableof being heated to at least 275 C.7.6.4 The detector shall have an independently controlledmakeup gas capability, capable of providing up to 5 mL minadditional flow of nitrogen, helium, or argon to the flow cell.7.7 Data Processing System, capable of storing an

35、d process-ing absorbance scan data and corresponding time.7.7.1 Data processing system shall include a database li-brary of vacuum ultraviolet reference spectra, compound classinformation, carbon number, density, and approximate reten-tion index values. Data processing system shall also storerelativ

36、e response factors for each hydrocarbon class in additionto relative response factors for individually reported com-pounds.7.7.2 Data processing system shall be capable of imple-menting equations and fit procedures that result in deconvolu-tion of absorbance spectra that contain contributions frommu

37、ltiple species.7.7.3 Data processing system shall be capable of binningand storing response contributions from each deconvolutionanalysis and reporting a combined total response at the end ofthe analysis.7.7.4 Data processing system shall be capable of imple-menting equations to convert response are

38、as to percent massand further convert percent mass to percent volume.8. Reagents and Materials8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of t

39、he American Chemical Society wheresuch specifications are available.4Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.8.2 Nitrogen, helium, or hydrogen carrier gas for gaschro

40、matograph, 99.999 % pure.8.3 Nitrogen, helium, or argon purge/makeup gas forvacuum ultraviolet detector, 99.999 % pure.8.4 Methylene chloride, reagent grade, used as a solvent testsample and GC rinse solvent. (WarningToxic material. Maybe combustible at high temperatures.)8.5 Response test sample, 5

41、00 ug mL benzene in methanolsolvent.8.6 Sample consisting of C4to C15linear alkanes, used asretention time markers (optional).8.7 A system validation mixture that complies with PracticeD4307, having the components and approximate concentra-tions given in Table 1. The concentrations of the preparedsy

42、stem validation mixture should be close to those in Table 1and shall otherwise be accurately known.8.7.1 The components of the system validation mixture maybe modified to include other components of particular rel-evance to the method. For example, the system validationmixture may include ethanol or

43、 methylnaphthalene, or both.8.7.2 The components of the system validation mixture maybe modified to include linear alkanes or other compoundsnecessary for determining a retention time marker list (see 12.1and 12.2).8.7.3 The concentrations in Table 1 may be suitably modi-fied to accommodate addition

44、al or substituted components. Theconcentrations shall otherwise be accurately known.8.8 Aquality control (QC) sample, consisting of automotivespark-ignition engine fuel, similar in characteristics to samplesthat are to be routinely analyzed. The QC sample should beroutinely analyzed and the results

45、compared to their valuesobtained on initial setup of the instrumentation or replenish-ment of the QC stock supply. See Note 1.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American C

46、hemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 1 System Validation MixtureComponent Concentration (percent mass)Cyclopentane 1.1n-Pe

47、ntane 1.1Cyclohexane 2.12,3-Dimethylbutane 2.1n-Hexane 2.11-Hexene 1.5Methylcyclohexane 44-Methyl-1-hexene 1.6n-Heptane 3.51,2-Dimethylcyclohexane 5Isooctane 5n-Octane 51,2,4-Trimethylcyclohexane 4n-Nonane 4.5n-Decane 4.5n-Undecane 3.5n-Dodecane 3.5Benzene 2.2Toluene 2.2trans-Decahydronaphthalene 4n

48、-Tetradecane 4.5Ethylbenzene 4.5o-Xylene 4n-Propylbenzene 51,2,4-Trimethylbenzene 4.51,2,3-Trimethylbenzene 51,2,4,5-Tetramethylbenzene 5Pentamethylbenzene 5Total Paraffins 32.2Total Isoparaffins 7.1Total Olefins 3.1Total Naphthenes 20.2Total Aromatics 37.4Total Xylenes 4.0D8071 173NOTE 1Refer to Pr

49、actices D6299 and D6792 for guidance on qualityassurance (QA) practices.9. Hazards9.1 Many of the compounds in automotive spark-ignitionengine fuel or other test samples used in this test method aretoxic, flammable, or both. Safety and sample-handling proce-dures appropriate for working with such materials shall be inplace before attempting to use this test method.9.2 Hydrogen is flammable and potentially explosive if notproperly used. Use of hydrogen as a GC carrier gas shall onlybe done at laboratories experienced with its use, with propersafety procedures in pla