1、Designation: D6563 11Standard Test Method forBenzene, Toluene, Xylene (BTX) Concentrates Analysis byGas Chromatography1This standard is issued under the fixed designation D6563; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear 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 determination of the totalnonaromatic hydrocarbons, benzene, toluene, ethylbenzene
3、,xylenes, and total C9+ aromatic hydrocarbons in BTX con-centrates by capillary column gas chromatography. This testmethod is applicable to materials with a final boiling pointbelow 215C.1.2 This test method may also be used to determine therelative distribution of the individual C8aromatic hydrocar
4、bonisomers in mixed xylenes.1.3 Individual components can be determined from 0.01 to90 %.1.4 In determining the conformance of the test results usingthis method to applicable specifications, results shall berounded off in accordance with the rounding-off method ofPractice E29.1.5 The values stated i
5、n SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.6 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 hea
6、lth practices and determine the applica-bility of regulatory limitations prior to use. For a specificprecautionary statement, see Section 9.2. Referenced Documents2.1 ASTM Standards:2D3437 Practice for Sampling and Handling Liquid CyclicProductsD6809 Guide for Quality Control and Quality AssurancePr
7、ocedures for Aromatic Hydrocarbons and Related Ma-terialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE355 Practice for Gas Chromatography Terms and Rela-tionshipsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a
8、 Test MethodE1510 Practice for Installing Fused Silica Open TubularCapillary Columns in Gas Chromatographs2.2 Other Documents:OSHA Regulations, 29 CFR paragraphs 1910.1000 and1910.120033. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 extracted reformate, nan aromatic concentrat
9、e ob-tained by solvent extraction of reformate.3.1.2 reformate, nthe product of a catalytic process thatincreases the concentration of aromatic hydrocarbons.3.1.3 pyrolysis gasoline, ndepentanized by-product re-covered from ethylene manufacture.3.1.4 synthetic blend, nblend of reagent hydrocarbonsth
10、at simulate a process product.3.1.5 hydrogenated pyrolysis gasoline, npyrolysis gaso-line that has been treated with hydrogen to reduce the olefinscontent.3.1.6 crude ethylbenzene, nproduct produced from thereaction of impure fluid cat cracking, (FCC) ethylene andbenzene.3.1.6.1 DiscussionIt typical
11、ly contains greater than 40 %of ethylbenzene and benzene.3.1.7 light blending aromatics feedstock, nlight aromaticsfraction (with high amounts of benzene and toluene) typicallyrecovered from the isomerization of a p-xylene or m-xylenedepleted C8aromatics stream.3.1.8 mixed xylenes, na mixture of C8a
12、romatic hydrocar-bon isomers including ethylbenzene, but excluding stryene.1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.01 on Benzene, Toluene, Xylenes, Cyclohexane and TheirDerivat
13、ives.Current edition approved Feb. 1, 2011. Published February 2011. Originallyapproved in 2000. Last previous edition approved in 2010 as D6463 05 (2010)1.DOI: 10.1520/D6563-11.2For 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.3Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.1*A Summary of Chang
15、es 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.4. Summary of Test Method4.1 The specimen to be analyzed is injected into a gaschromatograph equipped with a flame ionization detector (FID
16、)and a capillary column. The peak area of each component ismeasured and adjusted using effective carbon number (ECN)response factors. The concentration of each component iscalculated based on its relative percentages of total adjustedpeak area and normalized to 100.00. To determine the relativedistr
17、ibution of C8aromatic hydrocarbons, the peak areas ofthose components only are normalized to 100.00.4.2 Results can be reported as either volume or weightpercent. Volumetric results can be derived by dividing eachcomponents weight percent by its relative density and re-normalizing to 100 %.5. Signif
18、icance and Use5.1 This test method was primarily developed to determinebenzene, toluene, and xylenes in chemical intermediate andsolvent streams such as reformate, BTX extracts, pyrolysisgasoline, hydrogenated pyrolysis gasoline, crude benzene,crude ethylbenzene, commercial toluene, and light blendi
19、ngaromatic feedstocks. This test method may not detect allcomponents and there may be unknown components thatwould be assigned inappropriate response factors and thus, theresults may not be absolute.5.2 The relative distribution of C8aromatics is useful fordetermining conformance to p-xylene feedsto
20、ck specifications.6. Interferences6.1 Nonaromatic hydrocarbons may interfere with the de-termination of benzene and toluene when certain columns areused.6.2 Styrene may be present in some samples. It will elutewith C9+ aromatics.7. Apparatus7.1 Gas ChromatographAny gas chromatograph having aflame io
21、nization detector and a splitter injector suitable for usewith a fused silica capillary column may be used, provided thesystem has sufficient sensitivity, linearity, and range to obtain aminimum peak height response for a 0.01 % peak of five timesthe height of the signal background noise, while not
22、exceedingthe full scale of either the detector or the electronic integrationfor the highest peak. The split injection system shall notdiscriminate over the boiling range of the samples analyzed.The system shall be capable of operating at the conditionsgiven in Table 1.7.2 ColumnsThe choice of column
23、 is based upon resolu-tion requirements. Any column may be used that is capable ofresolving all the components of interest. The column andconditions described in Table 1 have been used successfullyand will be the referee in case of dispute.7.3 Recorder/Electronic IntegrationElectronic integrationwit
24、h tangent capabilities is recommended.8. Reagents8.1 Carrier GasHelium with a minimum purity of 99.99mol %.8.2 Detector GasHydrogen with a minimum purity of99.99 mol %.8.3 Flame Support GasAir, total, hydrocarbon less than 5ppm.9. Hazards9.1 Consult current OSHA regulations, suppliers MaterialSafety
25、 Data Sheets, and local regulations for all material usedin this test method.10. Sampling10.1 Sample material in accordance with Practice D3437.11. Preparation of Apparatus11.1 ChromatographFollow manufacturers instructionsfor mounting and conditioning the column in the chromato-graph. Adjust the in
26、strument to the conditions as described inTable 1 to give the desired separation using the suggestedcolumn. Other columns may require different conditions toachieve the resolution requirements. Allow sufficient time forthe instrument to reach equilibrium as indicated by a stablerecorder/electronic b
27、aseline. See Practices E355 and E1510 foradditional information on gas chromatography practices andterminology.12. Procedure12.1 Bring the sample to ambient room temperature.12.2 Inject an appropriate amount of sample into the chro-matograph that meets the criteria outlined in 7.1. See PracticesE355
28、 and E1510 for additional information on gas chromatog-raphy practices and terminology.12.3 Sample chromatograms are illustrated in Figs. 1-4.12.4 Measure the area of all peaks. The non-aromaticsfraction includes all peaks up to ethylbenzene (except for thepeaks assigned to benzene and toluene). Sum
29、 together all thenon-aromatic peaks as a total area. The C9+ aromatics fractionincludes all peaks eluting after m-xylene except for o-xylene.Sum together all the C9+ aromatic peaks as a total area.TABLE 1 Instrument ParametersColumn 50 or 60 m by 0.25 mm ID bondedpolyethylene glycol-fused silica cap
30、illary,internally coated to a 0.25-m thicknessCarrier gas heliumFlow, linear velocity at 70C, cm/s 20Split ratio 200:1Detector gasHydrogen flow rate, mL/min 30Air flow rate, mL/min 300Make-up flow rate, mL/min 30Sample size, L 0.5TemperaturesInjector, C 250Detector, C 300ColumnInitial, C 70Hold, min
31、 10Rate, C/min 5Final, C 200Hold, min 24D6563 112FIG. 1 Synthetic BlendD6563 113FIG. 2 Pyrolysis GasolineD6563 114FIG. 3 Extracted ReformateD6563 115FIG. 4 Mixed XylenesD6563 11613. Calculation13.1 Calculate the weight percent concentration of eachcomponent as follows:Ci5100 3 Ai3 ECNi(i 5 1nAi3 ECN
32、i!(1)where:Ci= concentration of component inweight percent,Ai= area of component, i peak,ECNi= effective carbon response factorfor component, and(i 5 1nAi3 ECNi! = the summation of all response cor-rected areas in the chromatogram.13.2 Calculate the volume percent concentration of eachcomponent as f
33、ollows:V 5100 C/D(i 5 1nC/D!(2)where:V = calculated vol % concentration of component,C = calculated wt % concentration of component from12.1,D = relative density of component, andi=1n= sum of the quotients C/D.13.3 Use the following effective carbon number (ECN)response factors for the calculations:
34、ComponentECN ResponseFactorA,BRelative DensityCat15.56CNon Aromatics 1.0000 0.7200 (average)Benzene 0.9100 0.8829Toluene 0.9200 0.8743Ethylbenzene 0.9275 0.8744p-Xylene 0.9275 0.8666m-Xylene 0.9275 0.8694o-Xylene 0.9275 0.8849C9+ aromatics 0.9333 0.8752 (average)AScanlon, J., T., and Willis, D., E.,
35、 “Calculation of Flame Ionization DetectorRelative Response Factors Using the Effective Carbon Number Concept” Journalof Chromatographic Science, Vol 23, August, 1985, pp. 333-339.BResponse Factors are relative to n-heptane.CDS#4APhysical Constants of Hydrocarbons C1through C10, ASTM, 1971.14. Repor
36、t14.1 Report the following information:14.1.1 All component concentrations to the nearest 0.01 wt(or vol) %.14.1.2 For concentrations less than 0.01 wt (or vol) %,report as 0.01 wt (or vol) %.15. Precision and Bias415.1 PrecisionThe following criteria should be used tojudge the acceptability of resu
37、lts obtained by this test method(95 % confidence level). The precision criteria were derivedfrom an interlaboratory study using data submitted by fourteenlaboratories (ten laboratories for mixed xylenes. Each inter-laboratory study participant was provided two gravimetricallyprepared BTX known sampl
38、es and three unknown samples ofvarying concentrations. Each sample was run twice on twodays by two different operators. Results of the interlaboratorystudy were calculated and analyzed using Practice E691.15.2 Intermediate Precision, (formerly Repeatability)Results in the same laboratory should not
39、be consideredsuspect unless they differ by more than 6 the amount shown inTable 2, Table 3, Table 4, Table 5, Table 6,orTable 7.Onthebasis of test error alone, the difference between two resultsobtained in the same laboratory on the same material will beexpected to exceed this value only 5 % of the
40、time.15.3 ReproducibilityResults submitted by each of twolaboratories should not be considered suspect unless they differby more than 6 the amount shown in Table 2, Table 3, Table4, Table 5,orTable 6. On the basis of test error alone, thedifference between two results obtained in different laborato-
41、ries on the same material will be expected to exceed this valueonly 5 % of the time.15.4 BiasFor mixed xylenes, the interlaboratory test uti-lized a sample prepared gravimetrically from individual fromindividual C8isomers obtained at the highest purity available.However, this sample has not been app
42、roved as an acceptablereference material and consequently bias has not been deter-mined.15.4.1 As an aid for the users in determining the possibilityof bias, calculated C8distributed for the round robin sample islisted in Table 7 as the “Expected Concentration.” The averagevalue for each C8isomer as
43、 calculated from the reportedconcentrations is listed as “Average Concentration Reported.”4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D16-1025. Supporting data formixed xylenes are available separately: Request Research Repo
44、rt RR:D16-1015.TABLE 2 Interlaboratory Precision and Reproducibility forSynthetic Blend SampleNOTE 1This data was calculated after removal of outliers usingPractice E691.ComponentConcentrationWeight %IntermediatePrecisionReproducibilityNonaromatics 22.447 0.296 1.746Benzene 42.891 0.781 1.887Toluene
45、 19.961 0.212 0.715Ethylbenzene 3.061 0.055 0.191Total xylenes 7.921 0.195 0.512C9+ aromatics 4.192 0.169 1.009TABLE 3 Interlaboratory Precision and Reproducibility forPyrolysis Gasoline SampleNOTE 1This data was calculated after removal of outliers usingPractice E691.ComponentConcentrationWeight %I
46、ntermediatePrecisionReproducibilityNonaromatics 17.918 0.237 1.394Benzene 36.580 0.666 1.610Toluene 17.117 0.181 0.613Ethylbenzene 1.519 0.027 0.095Total xylenes 6.271 0.154 0.406C9+ aromatics 20.419 0.823 4.917D6563 11716. Quality Guidelines16.1 Laboratories shall have a quality control system inpl
47、ace.16.1.1 Confirm the performance of the test instrument ortest method by analyzing a quality control sample followingthe guidelines of standard statistical quality control practices.16.1.2 A quality control sample is a stable material isolatedfrom the production process and representative of the s
48、amplebeing analyzed.16.1.3 When QA/QC protocols are already established inthe testing facility, these protocols are acceptable when theyconfirm the validity of test results.16.1.4 When there are no QA/QC protocols established inthe testing facility, use the guidelines described in GuideD6809 or simi
49、lar statistical quality control practices.17. Keywords17.1 BTX concentrates; BTX extracts; capillary gas chro-matography; commercial toluene; crude benzene; crude ethyl-benzene; hydrogenated pyrolysis gas; light blending aromaticfeedstock; mixed xylenes; pyrolysis gasSUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to this standard since the last issue(D6563 - 05 (2010)1) that may impact the use of this standard. (Approved February 1, 2011.)(1) Deleted paragraph 13.4.ASTM International takes no positio
