1、Designation: D3524 14Standard Test Method forDiesel Fuel Diluent in Used Diesel Engine Oils by GasChromatography1This standard is issued under the fixed designation D3524; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 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 use of gas chromatographyto determine the amount of diesel fuel in used engine lubricat-i
3、ng oil. This test is limited to SAE 30 oil. The diesel fueldiluent is analyzed at concentrations up to 12 mass %.NOTE 1This test method may be applicable to higher viscosity gradeoils. However, such oils were not included in the program used to developthe precision statement.1.2 This test method is
4、limited to gas chromatographsequipped with flame ionization detectors and temperatureprogrammable ovens.NOTE 2The use of other detectors and instrumentation has beenreported. However, the precision statement applies only when the instru-mentation specified is employed.1.3 There is some overlap of th
5、e boiling ranges of dieselfuel and SAE 30 engine oils. Moreover, the boiling range ofSAE 30 oils from various sources can vary appreciably. As aresult, the calibration can be altered by as much as 2 %, interms of fuel dilution. When testing unknown or mixed brandsof used engine oil, it should be rea
6、lized that the precision of themethod may be poorer than the precision obtained whencalibrating with a new oil representative of the used oil beingtested.1.4 The values stated in SI units are to be regarded as thestandard. The values stated in inch-pound units are for infor-mation only.1.5 This stan
7、dard 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 and health practices and determine the applica-bility of regulatory requirements prior to use.2. Referenced Documents2.1
8、ASTM Standards:2D4626 Practice for Calculation of Gas ChromatographicResponse FactorsE260 Practice for Packed Column Gas ChromatographyE355 Practice for Gas Chromatography Terms and Relation-shipsE594 Practice for Testing Flame Ionization Detectors Usedin Gas or Supercritical Fluid ChromatographyE15
9、10 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs3. Terminology3.1 Definitions:3.1.1 For definition of gas chromatography terms, refer toPractice E355.3.2 Definitions of Terms Specific to This Standard:3.2.1 fuel dilution, nthe amount, expressed as apercenta
10、ge, of diesel fuel found in engine lubricating oil.3.2.1.1 DiscussionFuel dilution may be the result ofengine wear or improper performance.3.2.2 fuel diluent, nin used oil analysis, is the unburnedfuel components that enter the engine crankcase causingdilution of the oil.3.2.2.1 DiscussionIn this me
11、thod, the fuel diluent compo-nents being determined are from diesel fuel.3.3 Abbreviations:3.3.1 Acommon abbreviation of hydrocarbon compounds isto designate the number of carbon atoms in the compound. Aprefix is used to indicate the carbon chain form, while asubscripted suffix denotes the number of
12、 carbon atoms.For example: normal decane nC10iso-tetradecane iC141This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricantsand is the direct responsibility ofSubcommittee D02.B0 on Automotive Lubricants.Current edition approved May 1, 2014. P
13、ublished May 2014. Originallyapproved in 1976. Last previous edition approved in 2004 as D3524 04, whichwas withdrawn January 2013 and reinstated May 2014. DOI: 10.1520/D3524-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org.
14、For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*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 States14. S
15、ummary of Test Method4.1 Gas chromatographic techniques are used for analyzingthe samples, by adding a known percentage of n-decane as aninternal standard, in order to determine the mass percent ofdiesel fuel in the lubricating oil. A calibration curve ispreviously constructed which plots the diesel
16、 fuel to n-decaneresponse ratio versus the mass percent of diesel fuel inlubricating oil mixtures containing a constant amount ofinternal standard. The mass percent of diesel fuel in thesamples is determined by interpolation from the calibrationcurve.5. Significance and Use5.1 Some fuel dilution of
17、the engine oil may take placeduring normal operation. However, excessive fuel dilution is ofconcern in terms of possible performance problems. Thismethod provides a means to determine the magnitude of thefuel dilution, providing the user with the ability to predictperformance and to take appropriate
18、 action.6. Apparatus6.1 Gas ChromatographAny gas chromatograph can beused that has the following performance characteristics:6.1.1 DetectorA flame ionization detector is used. Thedetector must have sufficient sensitivity to detect 1.0 % decanewith a peak height of at least 10 % of full scale on the
19、dataacquisition device under the conditions prescribed in thismethod. Follow the directions given in Practice E594. Whenoperating at this sensitivity level, detector stability must besuch that a baseline drift of not more than 1 % full scale perhour is obtained. The detector must be capable of opera
20、tingcontinuously at a temperature equivalent to the maximumcolumn temperature employed. Connection of the column tothe detector must be such that no temperature zones existbelow the column temperature (cold spots). Although thermalconductivity detectors have been used for this test, their use isnot
21、recommended.NOTE 3It is not desirable to operate a thermal conductivity detector ata temperature 5 to 10C higher than the maximum column temperatureemployed. Operation at higher temperature generally contributes to highernoise levels and greater drift, and can also shorten the useful life of thedete
22、ctor.6.1.2 Column Temperature ProgrammerThe chromato-graph must be capable of linear programmed temperatureoperation over a range sufficient to establish a retention time ofat least 1 min for the initial peak(s) and to elute the entiresample before reaching the upper end of the temperatureprogram. T
23、he programming rate must be sufficiently reproduc-ible to obtain retention time repeatability of 0.1 min (6 s) foreach component in the calibration mixture described in 7.8.6.1.3 Sample Inlet SystemThe sample inlet system mustbe capable of operating continuously at a temperature equiva-lent to the m
24、aximum column temperature employed, or providean on-column inlet with some means of programming the inlet,including the point of sample introduction, up to the maximumtemperature required. Connection of the column to the sampleinlet system must be such that no temperature zones below thecolumn tempe
25、rature (cold spots) exist.6.2 Data Acquisition System:6.2.1 IntegratorMeans must be provided for determiningthe accumulated area under the chromatogram. This can bedone by means of an electronic integrator or computer basedchromatography data system. The integrator/computer systemmust have chromatog
26、raphic software for measuring the reten-tion times and areas of eluting peaks (peak detection mode).The electronic range of the integrator/computer (for example,1 V, 10 V) must be within the linear range of the detector/electrometer system used. It is desirable that the system becapable of subtracti
27、ng each area slice of a blank run from thecorresponding area slice of a sample run.NOTE 4Best precision and automatic operation can be achieved withan electronic integration system using a computer for data acquisition andcontrol of the gas chromatograph.NOTE 5Some gas chromatographs have an algorit
28、hm built into theiroperating software that allows a mathematical model of the baselineprofile to be stored in memory. This profile is automatically subtractedfrom the detector signal on subsequent sample analyses to compensate forany baseline offset. Some integration systems also store and automatic
29、allysubtract a blank analysis from subsequent analytical determinations.6.3 ColumnAny column and conditions may be used,provided that under the conditions of the test, the separationsoccur in order of increasing boiling points. Moreover, thecolumn must meet the performance requirements described in8
30、.2.1. The column resolution, R, shall be at least 3 and not morethan 8. Since a stable baseline is an essential requirement ofthis method, compensation is required for column bleed,septum bleed, detector temperature control, constancy ofcarrier gas flow and instrument drift.6.4 Flow ControllersThe g
31、as chromatograph must beequipped with mass flow controllers capable of maintainingcarrier gas flow constant to 61 % over the full operatingtemperature range of the column. The inlet pressure of thecarrier gas supplied to the gas chromatograph must be suffi-ciently high to compensate for the increase
32、 in column back-pressure as the column temperature is raised. An inlet pressureof 550 kPa (80 psig) has been found to be satisfactory with thecolumns described in Table 1.6.5 Sample Introduction Devices:6.5.1 Micro SyringeA micro syringe, usually 10 L, isused for sample introduction.6.5.2 Automatic
33、sampling devices that reproducibly injectthe same volume are highly recommended. The sample intro-duction devices should operate in a synchronous manner withthe gas chromatograph.6.6 Vial, 15-mL, screw cap.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tes
34、ts. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onD3524 142Analytical Reagents of the American Chemical Society wheresuch specifications are available.3Other grades may be used,provided it is first ascertained that the reagent is of suff
35、icientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Liquid Phase for ColumnsMethylsilicone gums andliquids provide the proper chromatographic hydrocarbon elu-tion characteristics for this test method.7.3 Solid SupportUsually crushed fire brick or diatoma-ceou
36、s earth is used for the packed columns. Sieve size andsupport loading should be such as will give optimum resolutionand analysis time. In general, particle size ranging from 60 to100 sieve mesh, and support loadings of 3 to 10 %, have beenfound most satisfactory.7.4 Carrier GasHelium or nitrogen (Wa
37、rningHeliumand nitrogen are compressed gases under high pressure), witha purity of 99.99 mole% or better. Additional purification isrecommended by the use of molecular sieves or other suitableagents to remove water, oxygen, and hydrocarbons. Availablepressure must be sufficient to ensure a constant
38、carrier gas flowrate (see 6.4).7.5 Hydrogen(WarningHydrogen is an extremelyflammable gas under high pressure) of high purity (99.99mole% or better) is used as fuel for the flame ionizationdetector (FID).7.6 AirCompressed air (WarningCompressed air is agas under high pressure and supports combustion)
39、, of highpurity (99.99 mole% or better) is used as the oxidant for theflame ionization detector (FID).7.7 Carbon Disulfide(WarningCarbon disulfide is ex-tremely volatile, flammable, and toxic).7.8 Calibration MixturesA minimum of three mixtures ofdiesel fuel and lubricating oil (WarningCombustible l
40、iquid)of a similar type to that being analyzed are prepared to coverthe range up to 12 mass % diesel fuel. If open tubular columnsare used, this calibration mixture shall be diluted 1/10 withcarbon disulfide (CS2).Diesel fuel, mass % 5mass of fuelmass of fuel and oil!3100 (1)7.9 n-Decane, 99 % minim
41、um purity. (WarningCombustible liquid; vapor harmful.)7.10 n-Hexadecane, 95 % minimum purity. (WarningCombustible liquid; vapor harmful.)7.11 n-Octadecane, 95 % minimum purity (WarningCombustible liquid; vapor harmful.)7.12 To test column resolution, prepare a mixture of 1volume % each of C16and C18
42、normal paraffins (WarningCombustible liquids; vapor harmful) in a suitable solvent suchas n-octane (WarningFlammable liquid; harmful if inhaled).If open tubular columns are used, this mixture shall be diluted1/10 with carbon disulfide (CS2). Inject the same volume ofthis mixture as to be used in sam
43、ple analysis and obtain thechromatogram by the procedure described in Section 10.8. Preparation of Apparatus8.1 Column Preparation:8.1.1 Packed ColumnsAny satisfactory method used inthe practice of gas chromatography (for example, see PracticeE260) that will produce a column meeting the requirements
44、 of6.3 may be used. The column must be conditioned at themaximum operating temperature until baseline drift due tocolumn bleeding has been reduced to a minimum.NOTE 6Difficulty in achieving the stable baseline requirement mayindicate injection port or column contamination. Remove and clean theinject
45、ion port. Reassemble and increase the temperature of the injectionport, column oven, and detector to the maximum limits of the gaschromatographic column employed.8.1.1.1 The packed column can be conditioned very rapidlyand effectively using the following procedure:3Reagent Chemicals, American Chemic
46、al Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Phar
47、macopeial Convention, Inc. (USPC), Rockville,MD.TABLE 1 Typical Operating ConditionsPacked Columns Open Tubular Capillary ColumnsColumn length, m (ft) 0.610 (2) 5 10Column outside diameter, mm (in.) 3.2 (1/8) Column inside diameter, mm (in.) 2.36 (0.093) 0.53Liquid phase methylsilicone gum or liquid
48、 cross-linked bonded polydimethylsiloxanePercent liquid phase 10 Support material crushed fire brick or diatomaceous earth Treatment acid washed, silanized Support mesh size 80/100 Stationary phase thickness, microns 0.88 2.65Column temperature, initial, C 70 70Column temperature, final, C 325 325Pr
49、ogramming rate, C/min 16 16Carrier gas helium or nitrogen helium or nitrogenCarrier gas flow rate, mL/min 30 30Detector Flame Ionization Detector Flame Ionization DetectorDetector temperature, C 350 350Injection port temperature, C 300 300Sample size, L 1 0.1 0.2 (from 1/10 dilution in CS2)D3524 143(1) Connect the column to the inlet, but leave the detectorend free.(2) Purge the column thoroughly at ambient temperaturewith carrier gas.(3) Turn off the carrier gas and allow the column todepressurize completely.(4) Seal of
