1、Designation: D6142 12D6142 16Standard Test Method forAnalysis of Phenol by Capillary Gas Chromatography1This standard is issued under the fixed designation D6142; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. 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 known impurities in phenol by gas chromatography (GC). It is generally meantfor
3、the analysis of phenol of 99.9 % or greater purity.1.2 This test method has been found applicable over impurity concentrations of 15 to 70 mg/kg. Users of this method believeit is linear over a wider range.1.3 In determining the conformance of the test results using this method to applicable specifi
4、cations, results shall be roundedoff in accordance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if a
5、ny, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific hazard statements, see Section 9.2. Referenced Documents2.1 ASTM Standards:2D3852
6、 Practice for Sampling and Handling Phenol, Cresols, and Cresylic AcidD4307 Practice for Preparation of Liquid Blends for Use as Analytical StandardsD4790 Terminology of Aromatic Hydrocarbons and Related ChemicalsD6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarb
7、ons and Related MaterialsE29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsE355 Practice for Gas Chromatography Terms and RelationshipsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE1510 Practice for
8、Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs2.2 Other Document:OSHA Regulations, 29 CFR paragraphs 1910.1000 and 1910.120033. Terminology3.1 See Terminology D4790 for definition of terms used in this test method.4. Summary of Test Method4.1 A known amount of an intern
9、al standard is added to a sample of phenol. The prepared sample is mixed and analyzed bya gas chromatograph equipped with a flame ionization detector (FID). The peak area of each impurity and the internal standardis measured. The amount of each impurity is calculated from the ratio of the peak area
10、of the internal standard versus the peakarea of the impurity. Results are reported in milligrams per kilogram.1 This test method is under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of SubcommitteeD16.02 on Oxygenated Aromati
11、cs.Current edition approved June 1, 2012June 1, 2016. Published June 2012June 2016. Originally approved in 1997. Last previous edition approved in 20082012 as D6142 08.12. DOI: 10.1520/D6142-12.10.1520/D6142-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Custo
12、mer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.
13、access.gpo.gov.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users co
14、nsult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocke
15、n, PA 19428-2959. United States15. Significance and Use5.1 This test method is suitable for setting specifications on phenol and for use as an internal quality control tool where phenolis produced or is used in a manufacturing process. It may also be used in development or research work involving ph
16、enol. It isgenerally applied to determining those commonly occurring impurities such as mesityl oxide, cumene, hydroxyacetone, acetone,alpha-methylstyrene, 2-methylbenzofuran, and acetophenone.5.2 Purity is commonly reported by subtracting the determined expected impurities from 100.00. However, a g
17、as chromato-graphic analysis cannot determine absolute purity if water is present or unknown components are contained within the materialbeing examined.6. Interferences6.1 The internal standard chosen must be sufficiently resolved from any impurity and the phenol peak.6.2 Any solvent used must also
18、be sufficiently resolved from any impurity, the internal standard, and the phenol peak.7. Apparatus7.1 Gas ChromatographAny chromatograph having a flame ionization detector that can be operated at the conditions givenin Table 1. The system should have sufficient sensitivity to obtain a minimum peak
19、height response for a 2 mg/kg impurity twicethe height of the signal background noise.7.2 ColumnsThe choice of column is based on resolution requirements.Any column may be used that is capable of resolvingall significant impurities from the major component. The column and conditions described in Tab
20、le 1 have been used successfullyand shall be used as referee in cases of dispute.7.3 RecorderElectronic integration is recommended.Chromatographic data systems are preferred but electronic integrationmay be used if the user can demonstrate that the results are consistent with the precision statement
21、. Recorders are not consideredadequate for meeting the precision requirements of this standard.8. Reagents8.1 Purity of ReagentReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analy
22、tical Reagents of the American Chemical Society, wheresuch specifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.8.2 High Purity Phenol(99.99 % or
23、greater purity).8.3 Carrier Gas, Makeup, and Detector GasesHelium, hydrogen, nitrogen, or other carrier, makeup and detector gases99.999 % minimum purity. Oxygen in carrier gas less than 1 ppm, less than 0.5 ppm is preferred. Purify carrier, makeup, anddetector gases to remove oxygen, water, and hyd
24、rocarbons.8.4 Compressed AirPurify air to remove water and hydrocarbons. Air for an FID should contain less than 0.1 ppm THC.4 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American
25、Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Dorset, U.K., and the United States Pharmacopeia and National Formulary,U.S. Parmacopeial Convention, Inc. (USPC), Rockville, MD.TABLE 1 Recommended Operating ConditionsColumn: To use for identification of all componentsColum
26、n: To use for identification of all componentsTubing fused silicaStationary phase polyethylene glycol-acid modifiedSolid support crosslinkedFilm thickness, 0.5Length, m 50Inside diameter, m 0.32Flow rate mL/min 1.3Temperature, CInjector 180Detector 230OvenInitial, C 110 for 6 minRate, C 12 per minFi
27、nal, C 210 for 90 minInternal Standard sec-butyl alcoholD6142 1628.5 Pure Compounds for Calibration, shall include mesityl oxide, cumene, hydroxyacetone, acetone, alpha-methylstyrene,2-methylbenzofuran, and acetophenone. The purity of all reagents should be 99.9 % or greater. If the purity is less t
28、han 99 %, theconcentration and identification of impurities must be known so that the composition of the standard can be adjusted for thepresence of the impurities.8.6 Internal Standardsec-Butylalcohol is one possible internal standard. However, other compounds may be found acceptableprovided they m
29、eet the criteria as defined in Section 6 and 8.5.9. Hazards9.1 Consult current OSHA regulations, suppliers Material Safety Data Sheets, and local regulations for all materials used inthis test method.10. Sampling and Handling10.1 Sample the material in accordance with Practice D3852.11. Preparation
30、of Apparatus11.1 Follow manufacturers instructions for mounting and conditioning the column into the chromatograph and adjusting theinstrument to the conditions described in Table 1.Allow sufficient time for the equipment to reach equilibrium. See Practices E355and E1510 for additional information o
31、n gas chromatography practices and terminology.12. Calibration12.1 Prepare synthetic mixtures of phenol with representative impurities on a weight basis. Weigh each impurity to the nearest0.0001 g.NOTE 1Phenol will freeze at room temperature. The sample and syringe must be kept warm to prevent freez
32、ing. An alternative is to add about 10 %by weight of a solvent such as methanol that will not be an interference in the chromatogram.12.2 Using the exact weight, or alternatively exact volumes and densities (see Table 2), calculate the mg/kg concentration foreach impurity in each calibration blend o
33、f 12.1.12.3 To a known weight of synthetic mixture, add a measured weight of sec-butyl alcohol as the internal standard. Calculatethe concentration of internal standard in mg/kg (25 to 50 mg/kg is reasonable). Mix well.12.4 Inject the resulting solution from 12.3 into the chromatograph. A typical ch
34、romatogram is illustrated in Fig. 1.Fig. 112.5 Determine the response factor for each impurity relative to sec-butyl alcohol by measuring the area under each peak andcalculate as follows:Ri 5 AsCi/CsAi (1)where:Ri = response factor for impurity i relative to the internal standard,Ai = peak area of i
35、mpurity i,As = peak area of the internal standard,Cs = concentration of the internal standard, mg/kg, andCi = concentration of impurity i, as calculated in 12.3, mg/kg.12.6 Calculate the response factors to the nearest 0.001.13. Procedure13.1 See 12.3 for the addition of the internal standard.13.2 D
36、epending upon the actual chromatographs operating conditions, charge an appropriate amount of sample into theinstrument.TABLE 2 Densities of CompoundsComponent Density at 25C (unless otherwise noted)Phenol 1.072 (at 45C)Acetone 0.791Mesityl oxide 0.853Cumene 0.862Hydroxyacetone 1.082-Methylstyrene 0
37、.9092-Methylbenzofuran 1.057Acetophenone 1.026sec-Butanol 0.808D6142 16313.3 Measure the area of all peaks except phenol. Measurements on the sample must be consistent with those made on thecalibration blend. A poorly resolved peak will often require a tangent skim from the neighboring peak. Make co
38、nsistentmeasurements on the sample and calibration chromatograms for tangents or poorly resolved peaks. A typical chromatogram isshown in Fig. 1.Fig. 1.14. Calculation14.1 Calculate the concentration of each impurity as follows:Ci 5 Ai! Ri! Cs!As!(2)15. Report15.1 Report the following information:15
39、.1.1 Individual impurities to the nearest 1 mg/kg, and15.1.2 For concentrations of impurities less than 2 mg/kg, report as 2 mg/kg and consider as 0 in summation of impurities.16. Precision and Bias16.1 PrecisionAn interlaboratory study was conducted which included seven laboratories. The data were
40、obtained over 1 dayusing the same operators. Each laboratory received one standard for calibration purposes plus two samples with two levels ofimpurities. Except for the use of only two materials, Practice E691 was followed for the design and analysis of the data.516.1.1 RepeatabilityResults in the
41、same laboratory should not be considered suspect unless they differ by more than theamount (r) shown in Table 3. Results differing by less than this amount have a 95 % probability of being correct.16.1.2 ReproducibilityResults submitted by two laboratories should not be considered suspect unless the
42、y differ by more thanthe amount shown (R) in Table 3. Results differing by less than this amount have a 95 % probability of being correct.16.2 BiasSince there is no accepted reference material suitable for determining the bias in this test method for measuringimpurities in phenol, bias has not been
43、determined.17. Quality Guidelines17.1 Laboratories shall have a quality control system in place.17.1.1 Confirm the performance of the test instrument or test method by analyzing a quality control sample following theguidelines of standard statistical quality control practices.17.1.2 Aquality control
44、 sample is a stable material isolated from the production process and representative of the sample beinganalyzed.17.1.3 When QA/QC protocols are already established in the testing facility, these protocols are acceptable when they confirmthe validity of test results.17.1.4 When there are no QA/QC pr
45、otocols established in the testing facility, use the guidelines described in Guide D6809 orsimilar statistical quality control practices.5 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D16-1021. Contact ASTM CustomerService at
46、 serviceastm.org.TABLE 3 Repeatability and ReproducibilityImpurity mg/kg Repeatability (r) Reproducibility (R)Acetone 18 1.9 3.373 3.7 10.3Acetophenone 16 1.1 1.470 3.2 18.9-Methylstyrene 20 1.5 4.351 2.0 5.6Cumene 17 4.0 4.070 4.9 10.9Hydroxyacetone 25 2.9 10.970 4.0 6.3Mesityl oxide 24 3.1 5.877 5
47、.3 16.42-Methylbenzofuran 17 1.9 4.963 3.0 12.3D6142 164FIG. 119 Typical Phenol Chromatogram Polyethylene Glycol - Acid Modified Column, Phenol MethodD614216518. Keywords18.1 2-methylbenzofuran; acetone; acetophenone; -methylstyrene; cumene; gas chromatography; hydroxyacetone; mesityloxide; phenol;
48、sec-butyl alcoholSUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to this standard since the last issue(D6142 - 08D6142)12) that may impact the use of this standard. (Approved June 1, 2012.)2016.)(1) Section 5 reference to cresols was removed.5Modified 7.3 regarding cu
49、rrent Editorial Guideline recommendations.(2) Section 7 modified to meet current editorial guidelines and Section 7.2.1 removed.Changed MSDS to SDS.(3) Section 8 modified to meet current editorial guidelines.Moved Table 2 to Section 12 and Table 3 to Section 16.(4) Section 12 reference to Fig. 2 removed.(5) Section 16 modified to meet current editorial guidelines. All references to Table 4 and the use of a (5 %-Phenyl)methylpolysiloxane column were removed.(6) Section 17 modified to meet current editorial guidelines.(7) Section 18
