1、Designation: D 6839 02An American National StandardStandard Test Method forHydrocarbon Types, Oxygenated Compounds and Benzenein Spark Ignition Engine Fuels by Gas Chromatography1This standard is issued under the fixed designation D 6839; the number immediately following the designation indicates th
2、e 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method provides for the quantitative de
3、termi-nation of saturates, olefins, aromatics and oxygenates inspark-ignition engine fuels by multidimensional gas chroma-tography. Each hydrocarbon type can be reported either bycarbon number (see Note 1) or as a total.NOTE 1There can be an overlap between the C9and C10aromatics;however, the total
4、is accurate. Isopropyl benzene is resolved from the C8aromatics and is included with the other C9aromatics.1.2 This test method is applicable to spark-ignition enginefuel with total aromatic content up to 50 % (V/V), total olefiniccontent up to 30 % (V/V) and oxygen compounds up to 15 %(V/V).1.3 Thi
5、s test method is not intended to determine individualhydrocarbon components except benzene.1.4 Oxygenates as specified in Test Method D 4815 havebeen verified not to interfere with hydrocarbons. Within theround robin sample set, the following oxygenates have beentested: MTBE, ethanol, ETBE, and TAME
6、. Other oxygenatescan be determined and quantified using Test Method D 4815 orD 5599.1.5 The values stated in SI units are to be regarded as thestandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of th
7、is standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 4307 Practice for Preparation of Liquid Blends for Use asAnalytical Standards2D 4815 Test Method for Determination of
8、MTBE, ETBE,TAME, DIPE tertiary-Amyl Alcohol and C1to C4Alco-hols in Gasoline by Gas Chromatography2D 5599 Test Method for Determination of Oxygenates inGasoline by Gas Chromatography and Oxygen SelectiveFlame Ionization Detection33. Terminology3.1 Definitions:3.1.1 oxygenate, nan oxygen-containing o
9、rganic com-pound, which may be used as a fuel or fuel supplement, forexample, various alcohols and ethers.3.2 Definitions of Terms Specific to This Standard:3.2.1 hydrogenation, nthe process of adding hydrogen toolefin molecules as a result of a catalytic reaction.3.2.1.1 DiscussionHydrogenation is
10、accomplished whenolefins in the sample contact platinum at a temperature of180C in the presence of hydrogen. The olefins are convertedinto hydrogen saturated compounds of the same carbon numberand structure. Monoolefins and diolefins convert to paraffinswhile cycloolefins and cyclodienes convert to
11、cycloparaffins.3.2.2 trap, na device utilized to selectively retain specificportions (individual or groups of hydrocarbons or oxygenates)of the test sample and to release the retained components bychanging the trap temperature.3.3 Acronyms:3.3.1 ETBEethyl-tert-butylether3.3.2 MTBEmethyl-tert-butylet
12、her3.3.3 TAMEtert-amyl-methylether4. Summary of Test Method4.1 A representative sample is introduced into a computercontrolled gas chromatographic system4consisting of switch-ing valves, columns, and an olefin hydrogenation catalyst, alloperating at various temperatures. The valves are actuated atpr
13、edetermined times to direct portions of the sample toappropriate columns and traps. As the analysis proceeds, the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04 on Hydrocarbon Analysis.Curren
14、t edition approved Nov. 10, 2002. Published February 2003.2Annual Book of ASTM Standards, Vol 05.02.3Annual Book of ASTM Standards, Vol 05.03.4The sole source of supply of the AC Reformulyzer known to the committee atthis time is AC Analytical Controls, Inc., 3494 Progress Dr., Bensalem, PA 19020.If
15、 you are aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, Wes
16、t Conshohocken, PA 19428-2959, United States.columns separate these sample portions sequentially intogroups of different hydrocarbon types that elute to a flameionization detector.4.2 The mass concentration of each detected compound orhydrocarbon group is determined by the application of re-sponse f
17、actors to the areas of the detected peaks followed bynormalization to 100 %. For samples containing methanol orother oxygenates that cannot be determined by this testmethod, the hydrocarbon results are normalized to 100 %minus the value of the oxygenates as determined by anothertest method such as T
18、est Method D 4815 or D 5599.4.3 The liquid volume concentration of each detected com-pound or hydrocarbon group is determined by application ofdensity factors to the calculated mass concentration of thedetected peaks followed by normalization to 100 %.5. Significance and Use5.1 A knowledge of spark-
19、ignition engine fuel compositionis useful for regulatory compliance, process control, andquality assurance.5.2 The quantitative determination of olefins and otherhydrocarbon types in spark-ignition engine fuels is required tocomply with government regulations.5.3 This test method is not applicable t
20、o M85 and E85 fuels,which contain 85 % methanol and ethanol, respectively.6. Interferences6.1 Some types of sulfur-containing compounds are irre-versibly adsorbed in the olefin trap reducing its capacity toretain olefins. Sulfur containing compounds are also adsorbedin the alcohol and ether-alcohol-
21、aromatic (EAA) traps. How-ever, a variety of spark-ignition engine fuels have beenanalyzed without significant performance deterioration of thesetraps.6.2 Commercial dyes used to distinguish between gradesand types of spark-ignition engine fuels have been found not tointerfere with this test method.
22、6.3 Commercial detergent additives utilized in spark-ignition engine fuels have been found not to interfere with thistest method.6.4 Dissolved water in spark-ignition engine fuels has beenfound not to interfere with this test method.7. Apparatus7.1 The complete system that was used to obtain theprec
23、ision data shown in Section 14 is comprised of a computercontrolled gas chromatograph, automated sample injector, andspecific hardware modifications. These modifications includecolumns, traps, a hydrogenator, and valves, which are de-scribed in 7.7, 7.8, and in Section 8. Fig. 1 illustrates a typica
24、linstrument configuration (see Note 5). Other configurations,components, or conditions may be utilized provided they arecapable of achieving the required component separations andproduce a precision that is equivalent to, or better than, thatshown in the precision tables.7.2 Gas Chromatograph, capab
25、le of temperature pro-grammed operation at specified temperatures, equipped with aheated flash vaporization inlet that can be packed (packedcolumn inlet), a flame ionization detector, necessary flowcontrollers, and computer control.7.3 Sample Introduction System, automatic liquid sampler,capable of
26、injecting a 0.1 L volume of liquid. The totalinjected sample shall be introduced to the chromatographicsystem thus excluding the use of split injections or carrier gaspurging of the inlet septum. An auto injector is recommendedbut optional.7.4 Gas Flow and Pressure Controllers, with adequateprecisio
27、n to provide reproducible flow and pressure of heliumto the chromatographic system, hydrogen for the hydrogenator,and hydrogen and air for the flame ionization detector. Controlof air flow for cooling specific system components and forautomated valve operation is also required.FIG. 1 Typical Instrum
28、ent ConfigurationD68390227.5 Electronic Data Acquisition System, shall meet or ex-ceed the following specifications (see Note 2):7.5.1 Capacity for 150 peaks for each analysis.7.5.2 Normalized area percent calculation with responsefactors.7.5.2.1 Area summation of peaks that are split or of groupsof
29、 components that elute at specific retention times.7.5.3 Noise and spike rejection capability.7.5.4 Sampling rate for fast (20 Hz to give10 points across peak).7.5.5 Peak width detection for narrow and broad peaks.7.5.6 Perpendicular drop and tangent skimming, as re-quired.NOTE 2Standard supplied so
30、ftware is typically satisfactory.7.6 Temperature Controllers of System ComponentsTheindependent temperature control of numerous columns andtraps, the hydrogenation catalyst, column switching valves, andsample lines is required. All of the system components thatcontact the sample shall be heated to a
31、 temperature that willprevent condensation of any sample component. Table 1 liststhe system components and operating temperatures (see Note3). Some of the components require isothermal operation, somerequire rapid heating and cooling, while one requires repro-ducible temperature programming. The ind
32、icated temperaturesare typical; however, the control systems utilized shall have thecapability of operating at temperatures 620C of those indi-cated to accommodate specific systems. Temperature controlmay be by any means that will meet the requirements listed inTable 1.NOTE 3The system components an
33、d temperatures listed in Table 1and Section 8 are specific to the analyzer used to obtain the precision datashown in Section 14. Other columns and traps that can adequately performthe required separations are also satisfactory but may require differenttemperatures.7.7 Valves, Column and Trap Switchi
34、ngAutomated, rotaryvalves are recommended. The valves shall be intended for gaschromatographic usage and meet the following requirements:7.7.1 The valves must be capable of continuous operation atoperating temperatures that will prevent sample condensation.7.7.2 The valves shall be constructed of ma
35、terials that arenonreactive with the sample under analysis conditions. Stain-less steel, PFA,5and Vespel5are satisfactory.7.7.3 The valves shall have a small internal volume but offerlittle restriction to carrier gas flow under analysis conditions.7.8 Valves, Airto control pressurized air for column
36、 andtrap cooling. Automated valves are recommended.NOTE 4New valves, tubing, catalyst, columns, traps, and othermaterials that contact the sample or gasses may require conditioning priorto operation in accordance with the manufacturers recommendations.7.9 Gas Purifiers, to remove moisture and oxygen
37、 fromhelium, moisture and hydrocarbons from hydrogen, and mois-ture and hydrocarbons from air.8. Reagents and Materials8.1 Air, compressed, 10 mg/kg each of total hydrocarbonsand H2O. (WarningCompressed gas under high pressurethat supports combustion.)8.2 Helium, 99.999 % pure, 0.1 mg/kg H2O. (Warni
38、ngCompressed gas under high pressure.)8.3 Hydrogen, 99.999 % pure, 0.1 mg/kg H2O.(WarningExtremely flammable gas under high pressure.)8.4 Columns, Traps, and Hydrogenation Catalyst (SystemComponents)This test method requires the use of fourcolumns, two traps, and a hydrogenation catalyst (see Note 3
39、).Each system component is independently temperature con-trolled as described in 7.6 and Table 1. Refer to Fig. 1 for thelocation of the components in the system (see Note 5). Thefollowing list of components contains guidelines that are to beused to judge suitability. The guidelines describe tempera
40、turesand times as used in the current system. Alternatives can beused provided that the separation as described is obtained andthe separation characteristics of the entire system are notlimited.NOTE 5Fig. 1 shows an additional trap, Molsieve 5A, and rotaryvalve V4 that are not required for this test
41、 method. They are included inFig. 1 because they were present in the instrumentation used to generatethe precision data. They can be used for more detailed analyses outside thescope of this test method, where an iso-normal paraffin, iso-normal olefindetermination is desired. There is no statistical
42、data included in this testmethod relating to their use.8.4.1 Alcohol TrapWithin a temperature range from 140to 160C, this trap must elute benzene, toluene, all paraffins,olefins, naphthenes, and ethers within the first 2 min aftersample injection while retaining C8+ aromatics, all alcohols,and any o
43、ther sample components.8.4.1.1 At a temperature of 280C, all retained componentsfrom 8.4.1 shall elute within 2 min of when the trap isbackflushed.8.4.2 Polar ColumnAt a temperature of 130C, thiscolumn must retain all aromatic components in the samplelonger than the time required to elute all non-ar
44、omatic com-ponents boiling below 185C, within the first 5 min aftersample injection.5PFA and Vespel are trademarks of E. I. DuPont de Nemours and Co.TABLE 1 Temperature Control Ranges of System ComponentsComponentTypical OperatingTemperatureRange, CMaximumHeatingTime, minMaximumCoolingTime, minAlcoh
45、ol trap 60280 2 5Polar column 130 isothermalNon-polar column 130 isothermalOlefin trap 120280 1 5Molsieve 13X column 90430 Temperatureprogrammed, 10/minPorapak column 130140 isothermalEther-alcohol-aromatic(EAA) trap70280 1 5Hydrogenation catalyst 180 isothermalColumn switching valves 130 isothermal
46、Sample lines 130 isothermalD68390238.4.2.1 The column shall elute benzene, toluene, and allnon-aromatic components with a boiling point below 215Cwithin 10 min of the introduction of these compounds into thecolumn.8.4.2.2 This column shall elute all retained aromatic com-ponents from 8.4.2 within 10
47、 min of when this column isbackflushed.8.4.3 Non-Polar ColumnAt a temperature of 130C, thiscolumn shall elute and separate aromatics by carbon numberboiling below 200C. Higher boiling paraffins, naphthenes, andaromatics are backflushed.8.4.4 Olefin TrapWithin a temperature range from 90 to105C, this
48、 trap shall retain (trap) all olefins in the sample forat least 6.5 min and elute all non-olefinic components up to C7in less than 6.5 min after the sample is injected. Non-olefiniccomponents C9and higher shall be retained during this time.8.4.4.1 Within a temperature range from 140 to 150C thistrap
49、 shall retain C6and higher olefins and elute all non-olefiniccomponents in 3 min. Olefins up to C6may or may not elute inthis time.8.4.4.2 At a temperature of 280C, this trap shall quantita-tively elute all retained olefins.8.4.5 Molsieve 13X ColumnThis column shall separateparaffin and naphthene hydrocarbons by carbon number whentemperature programmed from 90 to 430C at approximately10/min.8.4.6 Porapak ColumnAt a temperature from 130 to140C, this column shall separate individual oxygenates,benzene, and toluene.8.4.7 Ether-Alcohol-Aromat
