ASTM D8144-2018 6875 Standard Test Method for Separation and Determination of Aromatics Nonaromatics and FAME Fractions in Middle Distillates by Solid-Phase Extraction and Gas Chro.pdf

1、Designation: D8144 18Standard Test Method forSeparation and Determination of Aromatics, Nonaromatics,and FAME Fractions in Middle Distillates by Solid-PhaseExtraction and Gas Chromatography1This standard is issued under the fixed designation D8144; the number immediately following the designation in

2、dicates 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. Scope1.1 This test method covers the separation a

3、nd determina-tion of representative aromatics, nonaromatics, and fatty acidmethyl ester (FAME) fractions in middle distillates that boilbetween 170 C and 400 C, including biodiesel blends with upto 20 % by volume of FAME, by solid phase extraction and gaschromatography.1.2 This test method provides

4、two procedures, A and B.Procedure A is applicable to the petroleum-based middledistillates fuel, and Procedure B is applicable to the biodieselblends with up to 20 % by volume of FAME.1.3 This test method is applicable to middle distillatessamples with aromatics content ranging from 5 % to 50 % byma

5、ss and biodiesel blends with FAME content in the range of0.5 % to 20 % by volume. This test method may apply toconcentrations outside these ranges, but the precision has notbeen determined.1.4 For Procedure B, biodiesels in the form of fatty acidethyl ester (FAEE) can also fully elute into the FAME

6、fraction,and they have the similar FID (flame ionization detector)relative response factors with that of FAME. The determinedcontent of FAME fractions are the sum of concentrations ofFAME and FAEE by this test method (see 3.1.5).1.5 From the investigation results obtained for FAMEdetermination, the

7、low concentrations of monoglycerides (usu-ally less than 0.5 % by mass in biodiesel blends) are notdetectable under the gas chromatographic (GC) condition ofthis test method and will not interfere with the determination ofFAME by Procedure B. As a result, biodiesel blends, conform-ing to the require

8、ments of Specification D7467, containing upto 20 % by volume of biodiesel blendstock meeting therequirements in Specification D6751, typically contain concen-trations of monoglycerides of less than 0.1 % by mass. Thediglycerides and triglycerides, if present, are not detected underthe GC condition o

9、f this test method due to their higher boilingpoints.NOTE 1If a sample is suspected of containing an abnormal FAMEbiodiesel feedstock than specified in Specification D6751, for example, asample contaminated with vegetable oil with a high level of totaltriglycerides, the content of mono-, di-, or tri

10、-glycerides in the isolatedFAME fraction may be determined using Test Method D6584. Samplescontaining biodiesels with a high amount of glycerides than specified inSpecification D6751 may contaminate the GC column and not recom-mended for this test method.1.6 The values stated in acceptable SI units

11、are to beregarded as the standard. No other units of measurement areincluded in this standard1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and en

12、vironmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Stan

13、dards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D2425 Test Method for Hydrocarbon Types in Middle Dis-tillates by Mass SpectrometryD2549 Test Method for Separation of Representative Aro-ma

14、tics and Nonaromatics Fractions of High-Boiling Oilsby Elution ChromatographyD2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas ChromatographyD4052 Test Method for Density, Relative Density, and APIGravity of Liquids by Digital Density Meter1This test method is under the

15、 jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.04.0L on Gas Chromatography Methods.Current edition approved March 1, 2018. Published April 2018. DOI: 10.1520/D8144-18.2For referenced ASTM standards, visit the

16、 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. Un

17、ited StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barrie

18、rs to Trade (TBT) Committee.1D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System

19、PerformanceD6584 Test Method for Determination of TotalMonoglycerides, Total Diglycerides, Total Triglycerides,and Free and Total Glycerin in B-100 Biodiesel MethylEsters by Gas ChromatographyD6751 Specification for Biodiesel Fuel Blend Stock (B100)for Middle Distillate FuelsD7467 Specification for

20、Diesel Fuel Oil, Biodiesel Blend(B6 to B20)2.2 Other Standards:3EN 14103 Fat and oil derivativesFattyAcid Methyl Esters(FAME)Determination of ester and linolenic acidmethyl ester contentsEN 14214 Automotive fuelsFatty acid methyl esters(FAME) for diesel enginesRequirements and test meth-ods3. Termin

21、ology3.1 Definitions of Terms Specific to This Standard:3.1.1 aromatics fraction, nthe portion of the sampledesorbed with the dichloromethane-ethyl alcohol mixture elu-ants (Procedure A) and dichloromethane-n-hexane eluants(Procedure B); the aromatics fraction may contain aromatics,condensed naphthe

22、nic-aromatics, aromatic olefins, and com-pounds containing sulfur, nitrogen, and oxygen atoms.3.1.2 biodiesel, na fuel comprised of mono-alkyl esters oflong chain fatty acids derived from vegetable oils or animalfats, designated B100.3.1.3 biodiesel blend, na blend of biodiesel fuel withpetroleum-ba

23、sed diesel fuel.3.1.4 diesel fuel, npetroleum-based middle distillate fuel.3.1.5 fatty acid methyl ester fraction, nthe portion of thediesel fuels blends with fatty acid methyl ester (FAME) elutedwith dichloromethane-ethyl alcohol; the FAME fraction maycontain FAEE and compounds containing nitrogen

24、and oxygenatoms.3.1.6 nonaromatics fraction, nthe portion of the sampleeluted with n-hexane.3.1.6.1 DiscussionThe nonaromatics fraction is a mixtureof paraffinic and naphthenic hydrocarbons if the sample is astraight-run material. If the sample is a cracked stock, thenonaromatics fraction will also

25、contain aliphatic and cyclicolefins.3.1.7 solid phase extraction separating system, na solid-phase extraction cartridge packed with stationary phase mate-rial to effectively separate the aromatics, nonaromatics, andother compounds (such as FAME) fractions in middle distil-lates based on the mechanis

26、m of solid phase extraction (SPE).4. Summary of Test Method4.1 Procedure AThe sample is charged to the top of a SPEcolumn and separated into aromatics and nonaromatics frac-tions by eluants with different polarities. Two aliquots ofinternal standards are added to these two fractions and bothfraction

27、s are analyzed by the gas chromatograph equipped withhydrogen flame ionization detector (GC-FID). The content ofthe aromatics and nonaromatics are calculated based on thepeak areas of the aromatics, nonaromatics, and internal stan-dards.4.2 Procedure BThe sample is charged to the top of a SPEcolumn

28、and separated into aromatics, nonaromatics, andFAME fractions by eluants with different polarities. Threealiquots of internal standards are added to these three fractions.All of these fractions are analyzed by the gas chromatographequipped with hydrogen flame ionization detector (GC-FID).The content

29、 of the aromatics, nonaromatics, and FAME frac-tions are calculated based on the peak areas of the aromatics,nonaromatics, FAME, and internal standards. The volumepercent of FAME is calculated based on the density of sampleand mass percent of FAME.5. Significance and Use5.1 For the middle distillate

30、s whose boiling range is be-tween 170 C and 400 C by such distillation methods like TestMethod D2887, Procedure A can separate and determine thecontent of total aromatics and total nonaromatics by SPE andGC analysis of the resulting fractions. The determination of thetotal content of saturates and a

31、romatics in petroleum middledistillates is useful to investigate the effects of petroleumprocesses on production of various finished fuels.5.2 The total aromatics content and polycyclic aromaticscontent are important to characterize the quality of diesel fuels.This test method is demonstrated to be

32、time-saving andeco-friendly by reducing the amount of reagent consumptionand avoiding the necessity of solvent evaporation step asrequired, for example, in such Test Method D2549.5.3 The determination of detailed hydrocarbon compositionby mass spectrometry requires a preliminary separation of thesam

33、ple into representative aromatics and nonaromatics, as inTest Method D2425, where Test Method D2549 is used toseparate the distillate fuel. The SPE fractionation proceduredescribed herein may provide a suitable fractionation alterna-tive approach for these mass spectrometric types of methods.5.4 Bio

34、diesel is a blendstock commodity primarily used as avalue-added blending component with diesel fuel. Procedure Bcan provide a separation and determination technique tomonitor the FAME content for FAME biodiesel blends.3Available from British Standards Institution (BSI), 389 Chiswick High Rd.,London

35、W4 4AL, U.K., http:/.D8144 1826. Apparatus6.1 Solid Phase Extraction Separating System:6.1.1 Solid Phase Extraction (SPE) Column,4as shown inFig. 1. The SPE column used in Section 11 is 3 mL columnpacked with 1.5 g stationary phase particles. The stationaryphase is a mixture 90:10 by mass of 75 m to

36、 150 m silica geland 75 m to 150 m neutral aluminum oxide. Appropriateseparation efficiency and activity are required for the SPEcolumn to obtain a satisfactory separation and quantificationresults. The detailed verification procedure and criteria for SPEcolumn separation efficiency are described in

37、 10.1.NOTE 2Any automated solid phase extraction instrument that canperform this separation procedure with the satisfied separation efficiencycan also be used.NOTE 3The SPE column may be stored in a dry atmosphere as longas its performance meets the specifications; the SPE column is disposableand is

38、 used only once.6.1.2 Erlenmeyer flask, 10 mL6.1.3 Syringe, 2 mL and 0.25 mL.6.1.4 Pipette, 1 mL.6.1.5 Analytical Balance, capable of weighing to the nearest0.0001 g.6.2 Gas Chromatographic (GC) SystemThe gas chro-matographic system shall be equipped with sample inletsystem, capillary column, column

39、 temperature programmer,FID detector and data acquisition system. Recommended GCoperating conditions are given in Table 1. The GC system andoperating conditions shall ensure baseline separation of thesolvent, sample and internal standard as shown in Fig. 2 andFig. 3. Any other gas chromatograph inst

40、rument and operatingconditions capable of yielding equivalent results may be used.6.2.1 Sample Introduction SystemManual or recom-mended automated liquid syringe injection into a splitting inletmay be employed. The sample amount reaching the column(combination of injection volume and split ratio) sh

41、ould meetthe requirement of separation efficiency and linear responsecalibration range.6.2.2 Capillary ColumnThis test method is limited to theuse of non-polar silica capillary columns. The column andconditions shall provide separation of typical petroleum hydro-carbons in order of increasing boilin

42、g point. See Fig. 2 and Fig.3 for examples of acceptable separation.6.2.3 DetectorThis test method requires a flame ioniza-tion detector (FID). The detector shall have enough sensitivity,linearity, and stability to meet performance requirements.6.2.4 Data Acquisition SystemA computerized data acqui-

43、sition and reporting system is required to acquire, display, andprocess GC data. The areas of chromatographic peaks can bedetermined through either manual or automated peak integra-tion.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in this test. Unless otherwise

44、 indicated, it is intended that4The sole source of supply of the apparatus (Solid Phase Extraction (SPE)Column that meets the requirements for this test method) known to the committeeat this time is Research Institute of Petroleum Processing, China Petroleum andChemical Corporation, 18 Xueyuan Road,

45、 Beijing 100083, P. R. China. 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,1which you may attend.1 Sample Inlet2 Adapter3 Solid Phase

46、Extraction Cartridge4 Sieve-plate5 Stationary Phase Particles6 Sample OutletFIG. 1 Solid Phase Extraction ColumnTABLE 1 Recommended Operating Conditions of GCAColumn Fused silica WCOT capillary columnSize 30m0.25mmID,filmthickness 0.25 mStationary phase Non-polar, such as 100 % dimethyl polysiloxane

47、or 5 % phenyl-methyl polysiloxaneColumn Temperature Program Initial oven temperature 60 C, initial hold 2 min,program rate 40 C min, final oven temperature300 C, final hold 5 minInletTemperature 300 CSplit ratio 20:1Sample size 0.5 LCarrier gasType Helium, Nitrogen, or HydrogenConstant Flow Mode 1 m

48、L minDetectorType Flame ionization detector (FID)Temperature 350 CFuel gas Hydrogen (30 mL/min)Oxidizing gas Air (300 mL/min)Make-up gas 25 mL/minAThe operating conditions given in this table are typical and may vary. The lengthof the WCOT column can be 15 m to 30 m; the inner diameter can be 0.15 m

49、m to0.32 mm. The suitable oven program can be selected to ensure baseline separa-tion of the solvent, sample ,and internal standard. See Fig. 2 and Fig. 3 forexamples of suitable resolution.D8144 183all reagents shall conform to the specifications of the Commit-tee onAnalytical Reagents of theAmerican Chemical Society,5where such specifications are available. Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determ