ASTM D7169-2011 8125 Standard Test Method for Boiling Point Distribution of Samples with Residues Such as Crude Oils and Atmospheric and Vacuum Residues by High Temperature Gas Chr.pdf

1、Designation: D7169 11Standard Test Method forBoiling Point Distribution of Samples with Residues Suchas Crude Oils and Atmospheric and Vacuum Residues byHigh Temperature Gas Chromatography1This standard is issued under the fixed designation D7169; the number immediately following the designation ind

2、icates 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. Scope*1.1 This test method covers the determinatio

3、n of the boilingpoint distribution and cut point intervals of crude oils andresidues by using high temperature gas chromatography. Theamount of residue (or sample recovery) is determined using anexternal standard.1.2 This test method extends the applicability of simulateddistillation to samples that

4、 do not elute completely from thechromatographic system. This test method is used to determinethe boiling point distribution through a temperature of 720C.This temperature corresponds to the elution of n-C100.1.3 This test method is used for the determination of boilingpoint distribution of crude oi

5、ls. This test method uses capillarycolumns with thin films, which results in the incompleteseparation of C4-C8in the presence of large amounts of carbondisulfide, and thus yields an unreliable boiling point distribu-tion corresponding to this elution interval. In addition, quench-ing of the response

6、 of the detector employed to hydrocarbonseluting during carbon disulfide elution, results in unreliablequantitative analysis of the boiling distribution in the C4-C8region. Since the detector does not quantitatively measure thecarbon disulfide, its subtraction from the sample using asolvent-only inj

7、ection and corrections to this region viaquenching factors, results in an approximate determination ofthe net chromatographic area.Aseparate, higher resolution gaschromatograph (GC) analysis of the light end portion of thesample may be necessary in order to obtain a more accuratedescription of the b

8、oiling point curve in the interval in question(see Appendix X1).1.4 This test method is also designed to obtain the boilingpoint distribution of other incompletely eluting samples such asatmospheric residues, vacuum residues, etc., that are charac-terized by the fact that the sample components are r

9、esolvedfrom the solvent.1.5 This test method is not applicable for the analysis ofmaterials containing a heterogeneous component such aspolyesters and polyolefins.1.6 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to S

10、I units that are provided for information onlyand are not considered standard.1.7 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 and health practices and deter

11、mine the applica-bility of regulatory limitations prior to use. Specific warningstatements are given in Section 8.2. Referenced Documents2.1 ASTM Standards:2D2887 Test Method for Boiling Range Distribution ofPetroleum Fractions by Gas ChromatographyD2892 Test Method for Distillation of Crude Petrole

12、um(15-Theoretical Plate Column)D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD6352 Test Method for Boiling Range Distribution ofPetroleum Distillates in Boiling Range from 174 to 700Cby Gas ChromatographyD6729 Test Method for Determination of Individual Com-ponents in Spark Ig

13、nition Engine Fuels by 100 MetreCapillary High Resolution Gas ChromatographyD6730 Test Method for Determination of Individual Com-ponents in Spark Ignition Engine Fuels by 100MetreCapillary (with Precolumn) High-Resolution Gas Chroma-tography1This test method is under the jurisdiction of ASTM Commit

14、tee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04.0H on Chromatographic Distribution Methods.Current edition approved May 1, 2011. Published July 2011. Originally approvedin 2005. Last previous editing approved in 2005 as D7169-05. DOI: 10.1520/D71691

15、1.2For 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.1*A Summary of Changes section appears at the end of this s

16、tandard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E594 Practice for Testing Flame Ionization Detectors Usedin Gas or Supercritical Fluid ChromatographyE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in G

17、as Chromatographs3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 cut point interval, nthe mass % obtained betweentwo selected temperatures of the interval.3.1.2 data acquisition rate, nthe speed of conversion ofthe analog signal to a digital signal, expressed in Hz (cycles/sec

18、ond).3.1.3 final boiling point (FBP), nthe temperature, forfully eluting samples (recovery = 100 %), at which 99.5 % ofthe sample is eluted.3.1.4 final elution time (FEt), nthe retention time of thecomponent of the reference time standard sample that elutes atthe end of the temperature ramp of the o

19、ven.3.1.5 final elution temperature (FET), nthe boiling pointof the normal paraffin that elutes at the time when the ovenreaches its final temperature.3.1.6 initial boiling point (IBP), nthe temperature corre-sponding to an accumulated 0.5 % of the total area of the elutedsample after correcting for

20、 the percent of sample recovery.3.1.7 quenching factor (QF), na number that corrects forthe diminished response due to the solvent profile co-elutingwith sample components.3.1.7.1 DiscussionData acquired during the quenchinginterval (QI) shall be corrected by applying the quenchingfactor.3.1.8 quenc

21、hing interval (QI), nthe time interval of thestart and end of elution of the CS2used as a solvent.3.1.8.1 DiscussionSample components that elute duringthis time interval shall be corrected by a factor due to theirdiminished response resulting from the co-elution of therelatively large amount of solv

22、ent present in the sample withthe light sample components.3.1.9 residue (R), nthe mass % of the sample that has noteluted at the temperature of calculation.3.1.9.1 DiscussionResidue is calculated from the %recov-ery.3.1.10 response factor (RF), nthe factor used in order tocalculate the %recovery of

23、the sample.3.1.10.1 DiscussionThe response factor is determinedfrom the net area of the standard (ASTD), mass of standard(MSTD), and mass of solvent (MSLSTD) used in the solution ofthe standard. A fully eluting sample, such as Reference Oil5010, is used in obtaining the response factor.3.1.11 sample

24、 area obtained (ASMP), nthe net chromato-graphic area (after baseline subtraction) obtained for thesample at the final elution time or temperature.3.1.12 slice, nthe reciprocal of the data acquisition rate;the time interval used to accumulate data, expressed in sec-onds.3.1.12.1 DiscussionNormally 0

25、.1 s is used. In caseswhere sample elutes immediately after injection, 0.05 s is used.3.1.13 start elution temperature (SET), nthe temperatureat which the first amount of hydrocarbon is detected by theflame ionization detector above a predetermined threshold.3.1.14 %recovery (RC), npercentage of the

26、 sample eluted.3.1.14.1 Discussion%Recovery is calculated from thesample area (ASMP), the response factor (RF), the sample mass,(MSMP), and the solvent mass (MSLSMP) used in sampledissolution.3.1.15 %recovery threshold (Rt), nif the %recovery fallsabove a preset limit, the sample is considered fully

27、 eluted andits recovery is assumed to be 100 %.3.1.15.1 DiscussionIf the %recovery values found forduplicate analyses of a nearly completely eluting sample are99.6 and 101.2 %, the %recovery threshold (Rt) may be set to99.6 % and thus either of these results may be considered asfully eluted and set

28、to 100 %.3.2 Symbols:ASMP= net area of the sampleASTD= net area of the response factor standardMSL= mass of solvent used in preparing sample solutionMSLSTD= mass of solvent used in preparing the responsefactor standard solutionMSMP= sample mass used in sample preparationMSTD= mass of the standard us

29、ed in preparing the responsefactor solution4. Summary of Test Method4.1 This is a gas chromatographic method utilizing an inletand a capillary column, both of which are subject to atemperature program. A flame ionization detector is used as atransducer that converts mass to an electrical signal A da

30、taacquisition system operating in the slice mode and chromatog-raphy software is used to accumulate the electronic signal. Aretention time calibration mixture is used to develop a retentiontime versus boiling point curve.Asolution of the Reference Oil5010, which fully elutes from the column under th

31、e conditionsof the test method and whose boiling point distribution hasbeen characterized in Test Method D6352, is used to determinethe detector response factor. Solvent injections are made, andthe resulting signal is subtracted from both the response factorstandard and the sample chromatogram. Fina

32、lly, the samplesolution is injected and with the use of the response factor, theamount of sample recovered is calculated.After converting theretention times of the sample slices to temperature, the boilingpoint distribution can be calculated up to the recoveredamount.5. Significance and Use5.1 The d

33、etermination of the boiling point distribution ofcrude oils and vacuum residues, as well as other petroleumfractions, yields important information for refinery operation.These boiling point distributions provide information as to thepotential mass percent yield of products. This test method mayprovi

34、de useful information that can aid in establishing opera-tional conditions in the refinery. Knowledge of the amount ofresidue produced is important in determining the economics ofthe refining process.6. Apparatus6.1 Gas ChromatographA gas chromatograph providedwith a cryogenic valve for cooling the

35、oven to sub ambientD7169 112temperatures is required. The conditions of operating the GasChromatograph are given in Table 1. It shall also have thefollowing components:6.1.1 Flame Ionization Detector (FID)A flame ionizationdetector capable of maintaining a temperature 5 to 10C higherthan the highest

36、 column temperature. The flame ionizationdetector should possess a jet orifice of about 0.018 in. (0.45mm) in order to delay the plugging of the orifice due to columnbleed. The FID should possess a sensitivity of 0.005coulombs/g (see Practice E594) and should have a linear rangeof 106.6.1.2 InletEit

37、her a temperature programmable inlet with aglass liner or a cool-on-column inlet can be used. The inletshall be capable of operating in a temperature-programmedmode from 50C to the final temperature of the oven. It isimportant that the temperature of the inlet, at any time duringthe analysis, be eit

38、her equal to or greater than the oventemperature. With the use of either inlet, frequent replacementof the liner or removal of a section of the column may berequired due to accumulation of non-volatile sample compo-nents. It is important that a leak free seal be reestablished afterreplacement of the

39、 liner or the removal of a small section of thecolumn.6.2 Carrier Gas Purification SystemGas purifiers are usedin order to remove traces of oxygen as well as moisture andother impurities present in the carrier gas. The purificationsystem should contain a hydrocarbon trap and an oxygen trap.The latte

40、r should preferably have a visible indicator in order toassess the remaining capacity of the oxygen trap.6.3 Data SystemA data system composed of a computerand software for data acquisition, which digitizes the detectorsignal, is recommended. Some instrumentation digitizes thesignal at the electrome

41、ter board in order to reduce noise. Thedata system is used at acquisition rates of about 10 Hz, whichcorrespond to slices of 0.1 s. This rate of data acquisition isnecessary to obtain a minimum number of slices void ofsample or solvent elution immediately after injection. Dataacquisition systems fac

42、ilitate the inspection of the baselineunder high magnification and allow the inspection of theretention time calibration mixture chromatogram. Retentiontime shifts can be measured. Overlaying chromatograms is alsopossible to ascertain similar signal amplitude.6.4 IntegratorAn integrator that digitiz

43、es the signal canalso be used to acquire chromatograms of the retention timecalibration mixture, the sample, the solvent and the referenceoil standard.6.5 Automatic Sample InjectorIt is mandatory to use anauto sampler since the external standard technique used in thisanalysis requires identical volu

44、mes for all injections.Addition-ally, small volumes (0.1 to 0.2 L) shall be injected in areproducible manner. Syringes of 5 to 10 L having needlegauges of size 23 to 26 are to be used.6.6 Carrier Gas ControlThe gas chromatograph shall beoperated under constant flow conditions. The flow rate at thebe

45、ginning of the oven temperature program shall not differ bymore than 1 % from the flow measured at the final oventemperature. Electronic pneumatic control is highly recom-mended.7. Column and Column Performance Criteria7.1 A100 % bonded polydimethylsiloxane column having anominal inside diameter of

46、0.5 mm and a film thickness of 0.09to 0.17 m is used.7.2 The column used should be capable of sustainingtemperatures of 435C under temperature programming. Alu-minum covered fused silica and metal columns have beensuccessfully used.7.3 The column should be capable of eluting carbon number100 at its

47、highest temperature. It is important that C100beeluted during the temperature program cycle of the oven.7.4 Column resolution is determined from the separation ofcarbons 50 and 52 in the retention time calibration mixturechromatogram. The resolution should be between 1.8 to 4.0.See Eq 1 in 13.1.7.5

48、The column shall be capable of allowing the start of theelution of n-C5prior to the solvent elution, which is CS2,at20C. The descending edge of the n-C5peak co-elutes withthe solvent. It is to be noted that at these low temperaturesliquid phases may turn solid, and retention shifts may beobserved du

49、ring the elution of compounds at these low oventemperatures.7.6 Column OverloadingThe prevention of column over-loading is carried out by determining the skewness of aselected peak among the components of the retention timecalibration mixture chromatogram. Any paraffin with a carbonnumber between C12and C24may be chosen. The skewnessshould be between 0.8 to 1.2. See Eq 2 in 13.2.7.7 Column FlowHelium is used as carrier. Column flowrate is set to 20 mL/min.TABLE 1 Gas Chromatographic ConditionsAInitial Oven Temperature 20CInitial Oven Time