1、Designation: D 3710 95 (Reapproved 2004)An American National StandardStandard Test Method forBoiling Range Distribution of Gasoline and GasolineFractions by Gas Chromatography1This standard is issued under the fixed designation D 3710; the number immediately following the designation indicates the y
2、ear 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 covers the determination of the boi
3、lingrange distribution of gasoline and gasoline components. Thistest method is applicable to petroleum products and fractionswith a final boiling point of 500F (260C) or lower asmeasured by this test method.1.2 This test method is designed to measure the entireboiling range of gasoline and gasoline
4、components with eitherhigh or low Reid vapor pressure and is commonly referred toas gas chromatography (GC) distillation (GCD).1.3 This test method has not been validated for gasolinescontaining oxygenated compounds (for example, alcohols orethers).1.4 The values stated in inch-pound units are to be
5、 regardedas the standard. The values given in parentheses are forinformation only.1.5 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 and health practices and d
6、etermine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see Note 9 and 7.2.2. Referenced Documents2.1 ASTM Standards:2D86 Test Method for Distillation of Petroleum Products atAtmospheric PressureD 323 Test Method for Vapor Pressure of Petroleum Prod-ucts (R
7、eid Method)D 1265 Practice for Sampling Liquefied Petroleum (LP)Gases (Manual Method)D 4057 Practice for Manual Sampling of Petroleum andPetroleum Products3. Terminology3.1 Definitions:3.1.1 final boiling point (FBP)the point at which a cumu-lative volume count equal to 99.5 % of the total volume co
8、untunder the chromatogram is obtained.3.1.2 initial boiling point (IBP)the point at which acumulative volume count equal to 0.5 % of the total volumecount under the chromatogram is obtained.3.1.3 relative molar responsethe measured area of acompound divided by the moles present in the syntheticmixtu
9、re relative to an arbitrarily chosen component.3.1.4 response factora constant of proportionality thatconverts area to liquid volume.3.1.5 system noisethe difference between the maximumand minimum area readings per second for the first 20 areareadings in the blank run.3.1.6 volume countthe product o
10、f the area under a peakand a response factor.4. Summary of Test Method4.1 The sample is introduced into a gas chromatographiccolumn which separates hydrocarbons in boiling point order.Conditions are selected so as to measure isopentane and lightersaturates discretely. Normal pentane and heavier comp
11、oundsare not completely resolved but are measured as pseudocomponents of narrow boiling range. The column temperatureis raised at a reproducible rate and the area under thechromatogram is recorded throughout the run. Boiling tem-peratures are assigned to the time axis from a calibration curve,obtain
12、ed under the same conditions by running a knownmixture of hydrocarbons covering the boiling range expectedin the sample. From these data the boiling range distribution ofthe sample is obtained.5. Significance and Use5.1 The determination of the boiling range distribution ofgasoline by GC distillatio
13、n provides an insight into thecomposition of the components from which the gasoline hasbeen blended. This insight also provides essential data neces-sary to calculate the vapor pressure of gasoline, which has beentraditionally determined byTest Method D 323. In addition, the1This test method is unde
14、r the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04 on Chromatographic Distribution Methods.Current edition approved Nov. 1, 2004. Published November 2004. Originallyapproved in 1978. Last previous edition approved in 19
15、99 as D 3710 99e1.2For referenced ASTM standards, visit 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.1Copyright ASTM International, 100 Barr Har
16、bor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Test Method D86 distillation curve can be predicted usingGCD data. See Annex A1.5.2 The GCD method facilitates online controls at therefinery, and its results offer improved means of describingseveral car performance parameters.
17、 These parameters include:(1) car-starting index, (2) vapor-lock index or vapor-liquidratio, and (3) warm-up index. The car-starting and vapor-lockindexes have been found to be mostly affected by the front endof the Test Method D86distillation curve (up to about 200F(93C). The warm-up index is affec
18、ted by the middle and to alesser extent by the back end of the Test Method D86curve,that is, the temperatures corresponding to the 50 to 90 % offrange. Since the boiling range distribution provides fundamen-tal information on composition, an improved expression for theabove performance parameters ma
19、y be worked out, even whenthe boiling range distribution curve is not smooth. Currently,car performance cannot be assessed accurately under suchconditions.6. Apparatus6.1 ChromatographAny gas chromatograph may be usedthat meets the performance requirements in Section 8. Place inservice in accordance
20、 with manufacturers instructions. Typicaloperating conditions are shown in Table 1.6.1.1 DetectorEither a thermal conductivity or a flameionization detector may be used. Detector stability must besuch that the sensitivity and baseline drift requirements asdefined in Section 8 are met. The detector a
21、lso must be capableof operating continuously at a temperature equivalent to themaximum column temperature employed, and it must beconnected to the column so as to avoid any cold spots.NOTE 1Care must be taken that the sample size chosen does not allowsome peaks to exceed the linear range of the dete
22、ctor. This is especiallycritical with the flame ionization detector. With thermal conductivitydetectors, sample sizes of the order of 1 to 5 L generally are satisfactory.With flame ionization detectors, the sample size should not exceed 1 L.NOTE 2It is not desirable to operate the detector at temper
23、atures muchhigher than the maximum column temperature employed. Operation athigher temperatures only serves to shorten the useful life of the detector,and generally contributes to higher noise levels and greater drift.6.1.2 Column Temperature ProgrammerThe chromato-graph must be capable of program t
24、emperature operation overa range sufficient to establish a retention time of at least 15 s forpropane and of allowing elution of the entire sample within areasonable time period. Subambient capability may be re-quired.The programming rate must be sufficiently reproducibleto meet the requirements of
25、8.7.NOTE 3If the column is operated at subambient temperature, exces-sively low initial column temperature must be avoided, to ensure that thestationary phase remains liquid. The initial temperature of the columnshould be only low enough to obtain a calibration curve meeting thespecifications of thi
26、s test method.6.1.3 Sample Inlet SystemThe sample inlet system mustbe capable of operating continuously at a temperature equiva-lent to the maximum column temperature employed, or provideon-column injection with some means of programming theentire column, including point of sample introduction up to
27、 themaximum temperature required. The sample inlet system mustbe connected to the chromatographic column so as to avoid anycold spots.6.1.4 Flow ControllersChromatographs must be equippedwith constant-flow controllers capable of holding carrier gasflow constant to 61 % over the full operating temper
28、aturerange.6.2 Sample IntroductionSample introduction may be ei-ther by means of a constant-volume liquid sample valve or byinjection with a microsyringe through a septum. If the sampleis injected manually, cool the syringe to 0 to 4C (32 to 40F)before taking the sample from the sample vial.NOTE 4Au
29、tomatic liquid-sampling devices or other sampling means,such as sealed septum-capped vials, may be used, provided no loss of lightends occurs. The system must be operated at a temperature sufficientlyhigh to vaporize completely hydrocarbons with an atmospheric boilingpoint of 500F (260C), and the sa
30、mpling system must be connected to thechromatographic column so as to avoid any cold spots.TABLE 1 Gas Chromatography Column and ConditionsColumn:Liquid phase, material UCW-982 Supelco 2100 UCW-98 OV-101 UCW-98weight % 10 20 10 10 10Solid support, material Chromosorb P Chromosorb W Chromosorb G Chro
31、mosorb P Supelcoportmesh size 80/100 80/100 60/80 60/80 80/100Length, m (ft) 0.5 (1.5) 1.5 (5) 0.9 (3) 1.2 (4) 1.5 (5)Outside diameter, mm (in.) 6.4 (1/4) 3.2 (1/5) 6.4 (1/4) 3.2 (1/8) 3.2 (1/8)Temperatures:Initial column temperature, C 30 40 20 0 0Final column temperature, C 250 250 200 250 230Dete
32、ctor temperature, C 250 250 345 250 250Injection zone temperature, C 250 300 345 250 230Operating Variables:Program rate, C/min 10.6 16 10 15 16Carrier gas He He He He Heflow rate, cm3/min 50 30 60 29 30Sample size, L 3 2 3 2 1Detector voltage (or mA) 150 mA 160 mA 135 mA . 175 mAInstrument:Detector
33、 type TC TC TC TC TCSampling system automatic syringe syringe syringe valve valveArea measurement method integrating A/D integrating A/D integrating A/D time slice time sliceTime slices per second 2 1/2 5 5 1/2D 3710 95 (2004)26.3 RecorderA recording potentiometer or equivalentwith a full-scale resp
34、onse time of2sorless may be used.6.4 ColumnAny column and conditions may be used,provided, under the conditions of the test method, separationsare in order of boiling points and the column meets theperformance requirements in Section 8. See Table 1 forcolumns and conditions that have been used succe
35、ssfully. Sincea stable baseline is an essential requirement of this test method,provisions must be made to compensate for column bleed.Traditionally this is done by using matching dual columns anddetectors.At best, this procedure is only marginally successful.An even more satisfactory procedure is t
36、o record the areaprofile of the column bleed during a blank run, and subtract thisprofile from subsequent sample runs, as outlined in 11.1.6.4.1 Column PreparationAny satisfactory method, usedin the practice of the art, that will produce a column meetingthe requirements of Section 8, may be used. Th
37、e column mustbe conditioned at the maximum operating temperature toreduce baseline shifts due to bleeding of column substrate.NOTE 5The column can be conditioned very rapidly and effectivelyby the following procedure:(1) Disconnect column from detector.(2) Purge the column thoroughly at ambient temp
38、erature with carriergas.(3) Turn off the carrier gas and allow the column to depressurizecompletely.(4) Raise the column temperature to the maximum operating tempera-ture and hold at this temperature for at least 1 h with no flow through thecolumn.(5) Cool the column to at least 100C before turning
39、on carrier gasagain.(6) Program the column temperature up to the maximum several timeswith normal carrier gas flow. The column then should be ready for use.NOTE 6An alternative method of column conditioning, which hasbeen found effective for columns with an initial loading of 10 % liquidphase, consi
40、sts of purging the column with carrier gas at the normal flowrate while holding the column at maximum operating temperature for 12to 16 h.6.5 IntegratorMeans must be provided for determiningthe accumulated area under the chromatogram. This can bedone by means of a computer, or automatic operation ca
41、n beachieved with electronic integration.Atiming device is used torecord the accumulated area at set time intervals. The samebasis for measuring time must be used to determine retentiontimes in the calibration, the blank, and the sample. If anelectronic integrator is used, the maximum area measureme
42、ntmust be within the linear range of the integrator.6.6 Sample ContainersPressure cylinders or vials withseptums should be provided for the calibration mixture andsamples to avoid loss of light ends.6.7 SystemAny satisfactory combination of the abovecomponents that will meet the performance requirem
43、ents ofSection 8.7. Reagents and Materials7.1 Calibration MixtureAsynthetic mixture of pure liquidhydrocarbons of known boiling point covering the boilingrange of the sample. At least one compound in the mixturemust have a boiling point equal to or lower than the initialboiling point of the sample,
44、and one compound must have aretention time greater than any component in the sample. Theconcentration of all compounds heavier than n-butane must beknown within 0.1 %. The synthetic composition shown inTable 1 should be used for gasoline analysis. Compoundsnecessary for evaluation of system performa
45、nce are noted inTable 2.NOTE 7If the sample contains significant quantities of compoundsthat can be identified on the chromatogram, these peaks may be used asinternal boiling point calibrations.NOTE 8Two calibration mixtures can be used for convenience. Onethat contains known concentrations of isope
46、ntane and heavier compoundscan be used for determining response factors, sensitivity, and concentra-tion repeatability. The other would contain a complete boiling range ofcompounds including propane, butane, and isobutane, whose concentra-tions are known only approximately. It would be used for meas
47、uringTABLE 2 Calibration MixturePeak Number Compound Identification NBP, FRelative Density,A60/60FApproximateVolume, %Typical ThermalConductivityResponse Factors1BnC344 0.5077 1 1.152BisoC411 0.5631 3 1.143BnC431 0.5844 10 1.074BisoC582 0.6248 9 1.085 nC597 0.6312 7 1.036 2-MeC5140 0.6579 5 1.037CnC
48、6156 0.6640 5 1.018D2,4-DiMeC5177 0.6772 5 1.079 nC7209 0.6882 9 1.0010CToluene 231 0.8719 10 0.8911 nC8258 0.7068 5 0.9812Cp-Xylene 281 0.8657 12 0.9013Cn-Propylbenzene 319 0.8666 4 0.9414 nC10345 0.7341 3 0.9915Cn-Butylbenzene 362 0.8646 3 0.9316CnC12421 0.7526 3 1.0017CnC13456 0.7601 2 1.0218 nC1
49、4486 0.7667 2 1.0419 nC15519 0.7721 2 1.05A“Selected Values of Properties of Hydrocarbons and Related Compounds,” American Petroleum Institute Project 44, Table 23-2, April 1956.BNecessary if sample contains isopentane and lighter compounds.CNecessary for system evaluation.DReplace 2-methylhexane (2-MeC6) or benzene if the sample contains more than 5 % benzene.D 3710 95 (2004)3resolution, skewness, retention time repeatability, polarity, and retentiontime-boiling point relationship.NOTE 9If the sample is known to contain more than
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1