1、Designation: D7169 16Standard 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 720 C.This temperature corresponds to the elution of n-C100.1.3 This test method is used for the determination of boilingpoint distribution of crude o
5、ils. 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 respons
6、e 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 in
7、jection 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
8、boiling point curve in the interval in questionas described in Test Method D7900 (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 fa
9、ct that the sample components are resolvedfrom 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 parenthes
10、es are mathematicalconversions to SI 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 sa
11、fety and health practices and determine 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 of Pe-troleum Fractions by Gas ChromatographyD2892 Test Met
12、hod for Distillation of Crude Petroleum(15-Theoretical Plate Column)D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD6352 Test Method for Boiling Range Distribution of Pe-troleum Distillates in Boiling Range from 174 C to700 C by Gas ChromatographyD7500 Test Method for Determina
13、tion of Boiling RangeDistribution of Distillates and Lubricating Base OilsinBoiling Range from 100 C to 735 C by Gas Chroma-tographyD7900 Test Method for Determination of Light Hydrocar-bons in Stabilized Crude Oils by Gas ChromatographyE594 Practice for Testing Flame Ionization Detectors Usedin Gas
14、 or Supercritical Fluid ChromatographyE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02
15、.04.0H on Chromatographic Distribution Methods.Current edition approved Oct. 15, 2016. Published November 2016. Originallyapproved in 2005. Last previous editing approved in 2011 as D7169 11. DOI:10.1520/D7169-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cu
16、stomer Service at serviceastm.org. 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
17、, PA 19428-2959. United States13. 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
18、Hz (cycles/second).3.1.3 final boiling point (FBP), nthe temperature, for fullyeluting samples (recovery = 100 %), at which 99.5 % of thesample 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
19、 ramp of the oven.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
20、correcting for 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 quenchingfact
21、or.3.1.8 quenching 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
22、amount of solvent 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
23、 %recovery of 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
24、.3.1.11 sample 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 Discuss
25、ionNormally 0.1 s is used. In cases wheresample 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), nperc
26、entage of the 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 cons
27、idered fully 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 setto 99.6 % and thus either of these results may be considered asfully e
28、luted and set to 100 %.3.2 Symbols:3.2.1 ASMPnet area of the sample3.2.2 ASTDnet area of the response factor standard3.2.3 MSLmass of solvent used in preparing sample solu-tion3.2.4 MSLSTDmass of solvent used in preparing the re-sponse factor standard solution3.2.5 MSMPsample mass used in sample pre
29、paration3.2.6 MSTDmass of the standard used in preparing theresponse factor 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 c
30、onverts mass to an electrical signal A dataacquisition 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 or
31、a gravimetric blend, which fully elutes from thecolumn under the conditions of the test method and whoseboiling point distribution have been characterized in TestMethod D6352 or D7500, is used to determine the detectorresponse factor. Solvent injections are made, and the resultingsignal is subtracte
32、d from both the response factor standard andthe sample chromatogram. Finally, the sample solution isinjected and with the use of the response factor, the amount ofsample recovered is calculated. After converting the retentiontimes of the sample slices to temperature, the boiling pointdistribution ca
33、n be calculated up to the recovered amount.5. Significance and Use5.1 The determination 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 a
34、s to thepotential mass percent yield of products. This test method mayprovide 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.D7169 1626. Apparatus6.1
35、Gas ChromatographA gas chromatograph providedwith a cryogenic valve for cooling the oven to sub ambienttemperatures is required. Typical conditions of operating theGas Chromatograph are given in Table 1. It shall also have thefollowing components:6.1.1 Flame Ionization Detector (FID)A flame ionizati
36、ondetector capable of maintaining a temperature 5 C to 10 Chigher than the highest column temperature. The flame ioniza-tion detector should possess a jet orifice of about 0.018 in.(0.45 mm) in order to delay the plugging of the orifice due tocolumn bleed. The FID should possess a sensitivity of0.00
37、5 coulombsg (see Practice E594) and should have a linearrange of 106.6.1.2 InletEither 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 50 C to the final temperature of the oven. It i
38、simportant that the temperature of the inlet, at any time duringthe analysis, be either 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-n
39、ents. It is important that a leak free seal be reestablished afterreplacement of the 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. T
40、he purificationsystem should contain a hydrocarbon trap and an oxygen trap.The latter 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 detec
41、torsignal, is recommended. Some instrumentation digitizes thesignal at the electrometer 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
42、ofsample or solvent elution immediately after injection. Dataacquisition systems facilitate 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 alsopos
43、sible to ascertain similar signal amplitude.6.4 Automatic Sample InjectorIt is mandatory to use anauto sampler since the external standard technique used in thisanalysis requires identical volumes for all injections.Additionally, small volumes (0.1 Lto 0.2 L) shall be injectedin a reproducible manne
44、r. Syringes of 5 L to 10 L havingneedle gauges of size 23 to 26 are to be used.6.5 Carrier Gas ControlThe gas chromatograph shall beoperated under constant flow conditions. The flow rate at thebeginning of the oven temperature program shall not differ bymore than 1 % from the flow measured at the fi
45、nal oventemperature. Electronic pneumatic control is highly recom-mended.7. Column and Column Performance Criteria7.1 A100 % bonded polydimethylsiloxane column having anominal inside diameter of 0.5 mm and a film thickness of0.09 m to 0.17 m is used.7.2 The column used should be capable of sustainin
46、gtemperatures of 435 C 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 highest temperature. It is important that C100beeluted during the temperature program cycle of the ove
47、n.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 The column shall be capable of allowing the start of theelution of n-C5prior to the solvent elution, w
48、hich is CS2,at20 C. 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 during the elution of compounds at these low oventemperatures.7.6 Column OverloadingThe prevention of c
49、olumn 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 and 2.0. See Eq 2 in 13.2.TABLE 1 Typical Gas Chromatographic ConditionsAInitial Oven Temperature 20 CInitial Oven Time 0 minOven Temperature Program 15 C minFinal Oven Temperature 425 C to 435 CBFinal Hold Time 10 minInlet Initial TemperatureC50 CInlet Temperature Prog
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