1、Designation: D 5135 07Standard Test Method forAnalysis of Styrene by Capillary Gas Chromatography1This standard is issued under the fixed designation D 5135; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of the impu-rities typically found in styrene and uses those values todetermine the pur
3、ity of styrene by difference by gas chroma-tography. Typical impurities in commercial styrene are foundin Table 1.1.2 This test method is applicable to impurity concentra-tions in the range of 0.001 to 1.00 % and for styrene purities of99 % or higher when using the internal standard procedure.1.3 In
4、 determining the conformance of the test results usingthis method to applicable specifications, results shall berounded off in accordance with the rounding-off method ofPractice E29.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thissta
5、ndard.1.5 This standard does not purport to address all the safetyconcerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use. For a specific
6、hazard statement, seeSection 9.2. Referenced Documents2.1 ASTM Standards:2D 3437 Practice for Sampling and Handling Liquid CyclicProductsD 4307 Practice for Preparation of Liquid Blends for Use asAnalytical StandardsD 4790 Terminology of Aromatic Hydrocarbons and Re-lated ChemicalsE29 Practice for U
7、sing Significant Digits in Test Data toDetermine Conformance with SpecificationsE 355 Practice for Gas Chromatography Terms and Rela-tionshipsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE 1510 Practice for Installing Fused Silica Open TubularCapil
8、lary Columns in Gas Chromatographs2.2 Other DocumentOSHA Regulations, 29 CFR paragraphs 1910.1000 and1910.120033. Terminology3.1 See Terminology D 4790 for definitions of terms used inthis test method.4. Summary of Test Method4.1 In this test method, the chromatogram peak area for eachimpurity is co
9、mpared to the peak area of the internal standard(n-heptane or other suitable known) added to the sample. Fromthe response factors of these impurities relative to that of theinternal standard and the amount of internal standard added,the concentration of the impurities are calculated. The styrenecont
10、ent is obtained by subtracting the total amount of allimpurities from 100.00.5. Significance and Use5.1 This test method is designed to obtain styrene purity onthe basis of impurities normally present in styrene and may beused for final product inspections and process control.1This test method is un
11、der the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10 AtomaticHydrocarbons.Current edition approved June 1, 2007. Published June 2007. Originallyapproved in 1990. Last pr
12、evious edition approved in 2002 as D 5135 02e1.2For 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.3Available fro
13、m U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.TABLE 1 Impurities Known or Suggested to be Present inCommercial StyreneEthylbenzeneo-xylenem-xylenep-xyleneIsopropylbenzenen-propylbenzenem-ethyltolue
14、nep-ethyltoluenea-methylstyrenem-vinyltoluenep-vinyltoluenePhenylacetylene1*A Summary 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.5.2 This test method will detect the impuriti
15、es shown inTable 1, non-aromatic hydrocarbons containing ten carbons orless, and others where specific impurity standards are available.Absolute purity cannot be determined if unknown impuritiesare present.6. Interferences6.1 The internal standard chosen must be satisfactorilyresolved from any impur
16、ity as well as the product peak.Apeakwill be satisfactorily resolved from a neighboring peak if thedistance from the valley to the baseline between the two peaksis not greater than 50 % of the peak height of the smaller of thetwo peaks.7. Apparatus7.1 Gas ChromatographAny instrument having a flameio
17、nization detector that can be operated at the conditions givenin Table 2. The system shall have sufficient sensitivity to obtaina minimum peak height response for 0.001 weight % impurityof twice the height of the background noise.7.2 ColumnA capillary column containing a stationaryphase of cross-lin
18、ked polyethylene glycol has been found to besatisfactory. Any column can be used that is capable ofresolving all significant impurities from styrene and from theinternal standard.7.3 RecorderElectronic integration, with tangent capabili-ties is recommended.7.4 100-mL Volumetric Flask.7.5 Microsyring
19、es, assorted volumes.8. Reagents and Materials8.1 Purity of ReagentReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee onAnalytical Reagents of theAmerican Chemical Society,4where such sp
20、ecifications are available.8.2 Carrier Gas, makeup and detector gases 99.999 %purity. Oxygen in carrier gas less than 1 ppm, less than 0.5 ppmis preferred. Purify carrier, makeup and detector gases toremove oxygen, water, and hydrocarbons.8.3 Air, purify to remove hydrocarbons and water. Airshould c
21、ontain less than 0.1 ppm THC.8.4 n-Heptane, 99.0 % minimum purity, or other internalstandard, such as n-octane, previously analyzed to be free ofcompounds coeluting with impurities in the sample.8.5 Styrene, the highest purity available, but not less than99.7 %.8.6 Pure Compounds, for calibration, s
22、hall be those com-pounds that are typically present in commercial styrene. Theseshould be at least 99 % pure as they are to be used fordetermining response factors.9. Hazards9.1 Consult current OSHA regulations, suppliers MaterialSafety Data Sheets, and local regulations for all materials usedin thi
23、s procedure.10. Sampling10.1 Sample the material in accordance with PracticeD 3437.11. Preparation of Apparatus11.1 Follow manufacturers instructions for mounting andconditioning the column into the chromatograph and adjustingthe instrument conditions described in Table 2, allowingsufficient time fo
24、r the equipment to reach equilibrium. SeePractices E 355 and E 1510 for additional information on gaschromatographic practices and terminology.12. Calibration12.1 Prepare a calibration mixture containing approximately99.5 weight % styrene and the expected significant impuritiesat their expected conc
25、entration (see Practice D 4307). Weighall components to the accuracy required to calculate theconcentration of each to the nearest 0.001 %.12.2 With a microsyringe, add 50 L of internal standard toa 100mL volumetric flask about three-fourths full of calibra-tion mixture. Mix well. Add calibration mi
26、xture to mark andagain mix well. If n-heptane is used as the internal standard,using a density of 0.684 for n-heptane and 0.906 for styrene,this solution will contain 0.0377 weight % n-heptane.12.3 Also prepare a sample of the styrene used for thecalibration blend with and without n-heptane to deter
27、mine theconcentration of existing impurities and interfering compoundswith internal standard. If impurities in the styrene emerge withthe chosen internal standard, an alternate internal standardmust be used.12.4 Inject an appropriate amount of sample into the chro-matograph and obtain a chromatogram
28、.12.5 Measure the areas of all peaks, including the internalstandard, except the styrene peak.12.6 Calculate the response factors for each impurity rela-tive to the internal standard as follows:4Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. F
29、or suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 2 Typical Instru
30、ment ParametersCarrier gas heliumCarrier gas flow rate at 110C, mL/min 1.2Detector flame ionizationDetector temperature, C 240Injection port temperature, C 230Hydrogen flow rate, mL/min 30Air flow rate, mL/min 275Make up gas nitrogenMake up gas flow rate, mL/min 23Split flow, mL/min 150Column 60 m 3
31、 0.32 mm ID 3 0.5 mbonded polyethylene glycol-fused silica capillaryColumn temperature, C 110Chart speed, cm/min 1Sample size, L 0.6D5135072RFi5CiCs!SAiAsi2AbAsbD(1)where:RFi= response factor relative to the internal standard,Asi= area of internal standard in calibration mixture,Ai= area of impurity
32、 peak in calibration mixture,Asb= area of internal standard in styrene used in makingcalibration mixture,Ab= area of impurity in styrene used to make calibrationmixture,Cs= weight percent internal standard in calibration mix-ture, andCi= weight percent impurity in calibration mixture.13. Procedure13
33、.1 Establish stable instrument operation at the prescribedor selected operating conditions. Reference should be made toinstructions provided by the manufacturer of the chromato-graph.13.2 Prepare sample as described in 12.2.13.3 Inject appropriate amount of sample into the chromato-graph and obtain
34、the chromatogram.Atypical chromatogram isshown in Fig. 1.14. Calculation14.1 Measure the areas of all peaks, including the internalstandard, except the styrene peak.14.2 Calculate the weight percent of the individual impuri-ties, Ci, as follows:Ci5Ai! RFi! Cs!As(2)where:Ai= area of impurity,As= area
35、 of internal standard,RFi= response factor for impurity, relative to the internalstandard, andCs= concentration of internal standard, in weight percent.14.3 Calculate the styrene content by subtracting the sum ofthe impurities from 100.00. Styrene weightpercent = 100.00 (sum of impurities).15. Repor
36、t15.1 Report the concentration of impurities to the nearest0.001 % and the styrene content to the nearest 0.01 %.16. Precision and Bias516.1 PrecisionThe following criteria should be used tojudge the acceptability (95 % probability level) of resultsobtained by this test method (see Practice E 691).
37、The criteriawere derived from a round robin among six laboratories. Thedata were run on two days using different operators.16.2 Intermediate PrecisionResults in the same labora-tory should not be considered suspect unless they differ bymore than the normal amount shown in Table 3 and Table 4.5Suppor
38、ting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D161031.FIG. 1 Typical Chromatogram (see Table 2)D513507316.3 ReproducibilityThe results by each of two laborato-ries should not be considered suspect unless they differ bymore than the
39、amount shown in Table 3 and Table 4.16.4 BiasBias of this test method for the analysis ofstyrene has not been determined because no acceptable refer-ence material is available.17. Quality Control17.1 Quality ControlConfirm the performance of theinstrument or the test method procedure by regularly an
40、alyzingQC samples.17.2 The following practice has been found to be effective.A sufficient quantity (5 gal) process sample of styrene iscollected and stored in a tightly sealed, stainless steel metalcan. This container is equipped with a stainless steel safetyfaucet, a pressure-relief cap and an inte
41、rnal flame arrestor. The5 gal can is kept in a refrigerator. Samples are withdrawn fromthis can once a week and transferred to a quart glass amberbottle that is fitted with a poly-seal cap. The material used forthe quality control sample is taken from the glass bottle, whichis not kept refrigerated.
42、18. Keywords18.1 analysis by gas chromatography; impurities in styrene;purity of styrene; styrene; styrene monomerSUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to this standard since the last issue(D 5135 - 02e1) that may impact the use of this standard. (Approved J
43、une 1, 2007.)(1) Editorial changes were made to 1.3 and 9.1.(2) 8.2 and 8.3 were modified to specify the purity of gasesused to conform to D16 Editorial Guidelines for gas chromato-graphic test methods.ASTM International takes no position respecting the validity of any patent rights asserted in conn
44、ection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the respons
45、ible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful c
46、onsideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 10
47、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM w
48、ebsite(www.astm.org).TABLE 3 Precision for Styrene and Impurities at Stated LevelsComponentConcentration,weight %IntermediatePrecision,%Reproducibility,%Styrene 99.74 0.017 0.054a-methylstyrene 0.028 0.0001 0.004Isopropylbenzene 0.008 0.001 0.001n-propylbenzene 0.004 0.0003 0.001m- and p-ethyltoluen
49、e 0.014 0.001 0.005p, m-xylene 0.125 0.005 0.007o-xylene 0.030 0.001 0.042TABLE 4 Precision for High Purity Styrene and Impurities atStated LevelsComponentConcentration,weight %IntermediatePrecision,%Reproducibility,%Styrene 99.96 0.024 0.033Ethylbenzene 0.014 0.003 0.004a-methylstyrene 0.007 0.002 0.003D5135074
