1、Designation: D 5191 07An American National StandardStandard Test Method forVapor Pressure of Petroleum Products (Mini Method)1This standard is issued under the fixed designation D 5191; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method cov
3、ers the use of automated vaporpressure instruments to determine the total vapor pressureexerted in vacuum by air-containing, volatile, liquid petroleumproducts. This test method is suitable for testing samples withboiling points above 0C (32F) that exert a vapor pressurebetween 7 and 130 kPa (1.0 an
4、d 18.6 psi) at 37.8C (100F) ata vapor-to-liquid ratio of 4:1. Measurements are made on liquidsample sizes in the range from 1 to 10 mL. No account is madefor dissolved water in the sample.NOTE 1Samples can also be tested at other vapor-to-liquid ratios,temperatures, and pressures, but the precision
5、and bias statements need notapply.NOTE 2The interlaboratory studies conducted in 1988, 1991, and2003 to determine the precision statements in Test Method D 5191 did notinclude any crude oil in the sample sets. Test Method D 6377, as well asIP 481, have been shown to be suitable for vapor pressure me
6、asurementsof crude oils.1.1.1 Some gasoline-oxygenate blends may show a hazewhen cooled to 0 to 1C. If a haze is observed in 8.5, it shallbe indicated in the reporting of results. The precision and biasstatements for hazy samples have not been determined (seeNote 14).1.2 This test method is suitable
7、 for calculation of the dryvapor pressure equivalent (DVPE) of gasoline and gasoline-oxygenate blends by means of a correlation equation (see Eq 1in 14.2). The calculated DVPE very closely approximates thedry vapor pressure that would be obtained on the same materialwhen tested by Test Method D 4953
8、.1.3 The values stated in SI units are regarded as standard.The inch-pound units given in parentheses are provided forinformation only.1.4 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 est
9、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific safetywarning statements, see 7.2 through 7.8.2. Referenced Documents2.1 ASTM Standards:2D 2892 Test Method for Distillation of Crude Petroleum(15-Theoretical Plate C
10、olumn)D 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4953 Test Method for Vapor Pressure of Gasoline andGasoline-Oxygenate Blends (Dry Method)D 6299 Practice for Applying Statistical Quality AssuranceTechniques to Evaluate Analytical Measurement SystemPerformanceD 6377 Test
11、Method for Determination of Vapor Pressure ofCrude Oil: VPCRx(Expansion Method)D 6378 Test Method for Determination of Vapor Pressure(VPX) of Petroleum Products, Hydrocarbons, andHydrocarbon-Oxygenate Mixtures (Triple ExpansionMethod)2.2 IP Standard:IP 481 Test Method for Determination of the Air Sa
12、turatedVapour Pressure (ASVP) of Crude Oil32.3 EPA Standard:40 CFR Part 80Appendix E, Method 3 Test for DeterminingReid Vapor Pressure (RVP) of Gasoline and GasolineOxygenate BlendsEvacuated Chamber Method43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 absolute vapor pressure
13、the pressure of the air-freesample. It is calculated from the total vapor pressure of thesample by subtracting out the partial pressure of the dissolvedair.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of Subcom
14、mitteeD02.08.0D on Vapor Pressure and V/L Ratio.Current edition approved May 1, 2007. Published July 2007. Originally approvedin 1991. Last previous edition approved in 2006 as D 519106e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at service
15、astm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from the Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K.4Available from the EPA Web site at http:/www.epa.gov/docs/epacfr40/chapt-I-info/1*A Summary
16、of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.2 dry vapor pressure equivalent (DVPE)a value cal-culated by a correlation equation (see 14.2) from the totalvapor pressure.3.1
17、.2.1 DiscussionThe DVPE is expected to be equivalentto the value obtained on the sample by Test Method D 4953,Procedure A.3.1.3 total vapor pressure (Ptot)the observed pressuremeasured in the experiment that is the sum of the partialpressure of the sample and the partial pressure of the dissolvedair
18、.3.2 Abbreviations:3.2.1 DVPEdry vapor pressure equivalent3.2.2 Ptottotal vapor pressure4. Summary of Test Method4.1 A known volume of chilled, air-saturated sample isintroduced into a thermostatically controlled, evacuated testchamber, or a test chamber with a moveable piston thatexpands the volume
19、 after sample introduction, the internalvolume of which is five times that of the total test specimenintroduced into the chamber. After introduction into the testchamber, the test specimen is allowed to reach thermal equi-librium at the test temperature, 37.8C (100F). The resultingrise in pressure i
20、n the chamber is measured using a pressuretransducer sensor and indicator. Only total pressure measure-ments (sum of the partial pressure of the sample and the partialpressure of the dissolved air) are used in this test method,although some instruments can measure the absolute pressureof the sample
21、as well.4.2 The measured total vapor pressure is converted to a dryvapor pressure equivalent (DVPE) by use of a correlationequation (see Eq 1 in 14.2).5. Significance and Use5.1 Vapor pressure is a very important physical property ofvolatile liquids.5.2 The vapor pressure of gasoline and gasoline-ox
22、ygenateblends is regulated by various government agencies.5.3 Specifications for volatile petroleum products generallyinclude vapor pressure limits to ensure products of suitablevolatility performance.5.4 This test method is more precise than Test MethodD 4953, uses a small sample size (1 to 10 mL),
23、 and requiresabout 7 min to complete the test.6. Apparatus6.1 Vapor Pressure ApparatusThe type of apparatus suit-able for use in this test method employs a small volume testchamber incorporating a transducer for pressure measurementsand associated equipment for thermostatically controlling thechambe
24、r temperature and for evacuating the test chamber priorto sample introduction or expanding the volume after sampleintroduction by a moveable piston.6.1.1 The test chamber shall be designed to contain between5 and 50 mL of liquid and vapor and be capable of maintaininga vapor-to-liquid ratio between
25、3.95 to 1.00 and 4.05 to 1.00.NOTE 3The test chamber employed by the instruments used ingenerating the precision and bias statements were constructed of stainlesssteel, aluminum, or brass.NOTE 4Test chambers exceeding a 15 mL capacity can be used, butthe precision and bias statements (see Section 16
26、) are not known to apply.6.1.2 The pressure transducer shall have a minimum opera-tional range from 0 to 177 kPa (0 to 25.7 psi) with a minimumresolution of 0.1 kPa (0.01 psi) and a minimum accuracy of60.8 kPa (60.12 psi). The pressure measurement system shallinclude associated electronics and reado
27、ut devices to displaythe resulting pressure reading.6.1.3 A thermostatically controlled heater shall be used tomaintain the test chamber at 37.8 6 0.1C (100 6 0.2F) forthe duration of the vapor pressure measurement.6.1.4 A platinum resistance thermometer shall be used formeasuring the temperature of
28、 the test chamber with a resolu-tion of 0.1C (0.2F) and an accuracy of 0.1C (0.2F).6.1.5 The vapor pressure apparatus shall have provisions forintroduction of the test specimen into an evacuated testchamber, or into a test chamber by a moveable piston, and forthe cleaning or purging of the chamber f
29、ollowing or precedingthe test.6.2 Vacuum Pump, capable of reducing the pressure in thetest chamber to less than 0.01 kPa (0.001 psi) absolute.6.3 Syringe, (optional, depending on sample introductionmechanism employed with each instrument) gas-tight, 1 to 20mL capacity with a 61 % or better accuracy
30、and a 61%orbetter precision. If a syringe is used to measure the samplevolume, the capacity of the syringe should not exceed twotimes the volume of the test specimen being dispensed.6.4 Iced Water Bath, Refrigerator, or Air Bath, for chillingthe samples and syringe to temperatures between 0 to 1C (3
31、2to 34F).6.5 Pressure Measuring Device, capable of measuring localstation pressure with an accuracy of 0.20 kPa (0.03 psi), orbetter, at the same elevation relative to sea level as theapparatus in the laboratory.6.5.1 When a mercury barometer is not used as the pressuremeasuring device, the calibrat
32、ion of the pressure measuringdevice employed shall be periodically checked (with traceabil-ity to a nationally recognized standard) to ensure that thedevice remains within the required accuracy specified in 6.5.6.6 McLeod Vacuum Gage or Calibrated Electronic VacuumMeasuring Device for Calibration, t
33、o cover at least the rangefrom 0.01 to 0.67 kPa (0.1 to 5 mm Hg). The calibration of theelectronic vacuum measuring device shall be regularly verifiedin accordance with the annex section on Vacuum Sensors(A6.3) of Test Method D 2892.7. Reagents and Materials7.1 Purity of ReagentsUse chemicals of at
34、least 99 %purity for verification of instrument performance (see Section11). Unless otherwise indicated, it is intended that all reagentsconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society where suchD5191072specifications are available.5Lower puritie
35、s can be used,provided it is first ascertained that the reagent is of sufficientpurity to permit its use without lessening the accuracy of thedetermination.7.1.1 The chemicals in sections 7.3, 7.4, 7.7, and 7.8(blended by mass with pentane) are suggested for verificationof instrument performance (se
36、e Section 11), based on thereference fuels analyzed in the 2003 interlaboratory study(ILS)6(see Table 1). Such reference fuels are not to be used forinstrument calibration. Table 1 identifies the accepted referencevalue (ARV) and uncertainty limits, as well as the acceptabletesting range for each of
37、 the reference fuels listed.NOTE 5Verification fluids reported by 28 of the 29 D 5191 data setparticipants in the 2003 ILS6included the following (with number of datasets identified in parenthesis): 2,2-dimethylbutane (18), cyclopentane (5),pentane (2), 2,3-dimethylbutane (1), 3-methylpentane (1), a
38、nd methanol(1).7.2 Cyclopentane,(WarningCyclopentane is flammableand a health hazard).7.3 2,2-Dimethylbutane,(Warning2,2-dimethylbutane isflammable and a health hazard).7.4 2,3-Dimethylbutane,(Warning2,3-dimethylbutane isflammable and a health hazard).7.5 Methanol,(WarningMethanol is flammable and a
39、health hazard).7.6 2-Methylpentane,(Warning2-methylpentane is flam-mable and a health hazard).7.7 Pentane,(WarningPentane is flammable and a healthhazard).7.8 Toluene,(WarningToluene is flammable and a healthhazard).8. Sampling8.1 General Requirements:8.1.1 The extreme sensitivity of vapor pressure
40、measure-ments to losses through evaporation and the resulting changesin composition is such as to require the utmost precaution andthe most meticulous care in the drawing and handling ofsamples.8.1.2 Obtain a sample and test specimen in accordance withPractice D 4057, except do not use the “Sampling
41、 by WaterDisplacement” section for fuels containing oxygenates. Useeither a 250-mL or 1-L (1-qt) sized container filled between 70and 80 % with sample. For best testing precision (reproduc-ibility), it is recommended that a 1-L sized container be used.NOTE 6The current precision statements were deri
42、ved from the 2003ILS6using samples in 250-mL and 1-L (1-qt) clear glass containers.However, samples in containers of other sizes, as prescribed in PracticeD 4057, may be used with the same ullage requirement if it is recognizedthat the precision can be affected. The differences in precision resultso
43、btained from 250-mL and 1-L containers were found to be statisticallysignificant, whereas there was no statistically observable bias detectedbetween 250-mL and 1-L containers. See Tables 2 and 3, as well as Figs.1 and 2 for more specific details on precision differences as a function ofDVPE value an
44、d container size. In general, numerically better repeatabil-ity values were determined at DVPE values 100 kPa, such as pentane, theprecision appears to worsen with diminishing liquid volume in the bottle.It is recommended that if pentane is used, that the % capacity in thecontainer be $50 %.11.2 Val
45、ues obtained within the acceptable testing rangeintervals in Table 1 indicate that the instrument is performingat the level deemed acceptable by this standard. If valuesoutside the acceptable testing range intervals are obtained,verify the quality of the pure compound(s) and re-check thecalibration
46、of the instrument (see Section 10).NOTE 1240 CFR Part 80 Appendix E, Method 3 provides additionalexamples of verification fluids available along with the Ptotlower andupper control limit reference values (that is, acceptance limits) identifiedfor each material. Just as in this test method, verificat
47、ion fluid resultsdetermined by the EPA method need to fall within the allowable range foracceptance. However, the tolerance intervals for pentane and 2,2 dimeth-ylbutane identified in the EPA method are tighter than in Table 1 of thistest method. In addition, the range covered in the EPA method for
48、thesetwo reference standards differ slightly from the range identified in Table 1,based on the separate EPA study that was conducted. In the EPA method,the Ptotreference value range for pentane is listed as 111.7 to 113.1 kPa(16.20 to 16.40 psi) and for 2,2 dimethylbutane as 73.4 to 75.4 kPa (10.64t
49、o 10.93 psi). Users of this test method that may also be analyzing samplesby the EPA method should be aware of the differences in the verificationfluid acceptance criteria that exist and need to meet the acceptance criteriaidentified in the corresponding method that is being followed.12. Quality Control Checks12.1 After having verified that the instrument is performingproperly, use a quality control (QC) sample that is representa-tive of the fuel(s) routinely tested by the laboratory to confirmthat the instrument is in statistical control followin
