1、Designation: E475 10Standard Test Method forAssay of Di-tert-Butyl Peroxide Using Gas Chromatography1This standard is issued under the fixed designation E475; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 assay of di-tert-butylperoxide using gas chromatography. It is applicable to com-mercial di-tert-buty
3、l peroxide which may contain smallamounts of isobutylene, tert-butanol, tert-butyl hydroperoxide,triisobutylenes, and water as impurities.1.2 Review the current appropriate Material Safety DataSheets (MSDS) for detailed information concerning toxicity,first aid procedures, and safety precautions.1.3
4、 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 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-p
5、riate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific hazardsstatements are given in Section 9.2. Referenced Documents2.1 ASTM Standards:2E203 Test Method for Water Using Volumetric Karl FischerTitration3. Terminology3.1 Definitions:3.1.1
6、 active oxygenthe oxidizing power present in organicperoxides expressed as oxygen (equivalent = 8.00).4. Summary of Test Method4.1 A sample is diluted in dodecane and injected into a gaschromatograph containing a wide-bore capillary column with anonpolar stationary phase. A temperature program is us
7、ed toseparate di-tert-butyl peroxide from impurities using helium asa carrier gas. The flame ionization detector response, propor-tional to component concentration, is recorded and the peakareas are measured. The concentration of di-tert-butyl peroxideis determined by area normalization after correc
8、ting for thearea of the solvent peak. The assay of di-tert-butyl peroxide iscorrected for water, which is determined using a separate KarlFischer titration since water is not detected using flameionization detection. The area percent of di-tert-butyl peroxideis assumed to be equal to mass percent.5.
9、 Significance and Use5.1 Di-tert-butyl peroxide is widely used as a catalyst andreaction initiator. Knowledge of the peroxide content is impor-tant in such applications. This test method provides a proce-dure for determining the active peroxide content of commercialdi-tert-butyl peroxide.6. Interfer
10、ences6.1 Interferences will be encountered if other componentsare present in the sample that have the same retention time asdi-tert-butyl peroxide.7. Apparatus7.1 InstrumentationGas chromatograph, capable of col-umn oven temperature programming from 40 to 160C at a rateof 10C/min and from 160 to 240
11、C at a rate of 35C/min.7.2 Injection SystemGlass-lined sample injection port,maintained at 150C.7.3 Sample IntroductionMicroliter syringes or automaticsyringe injectors, capable of delivering 0.5 L of a liquidsample, have been used successfully.7.4 DetectionFlame ionization detector, maintained at25
12、0C.7.5 Data Acquisition SystemElectronic data acquisitionand area integration capabilities are recommended.7.6 Chromatographic Column30 m wide-bore capillarycolumn (0.53 mm inside diameter) with a 5.0 m dimethylpol-ysiloxane stationary phase.8. Reagents and Materials8.1 Carrier Gas (Helium), chromat
13、ographic grade.8.2 Hydrogen, chromatographic grade.8.3 Compressed Air, oil-free.1This test method is under the jurisdiction of ASTM Committee E15 onIndustrial and Specialty Chemicals and is the direct responsibility of SubcommitteeE15.02 on Product Standards.Current edition approved March 1, 2010. P
14、ublished April 2010. Originallyapproved in 1973. Last previous edition approved in 2005 as E475 00(05). DOI:10.1520/E0475-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、refer to the standards Document Summary page onthe ASTM website.1*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.8.4 Dodecane, for use as a sample diluent, 99 % or grea
16、terchromatographic purity.9. Hazards9.1 Organic peroxides are strong oxidizing agents andpresent potential fire and explosion hazards. While di-tert-butyl peroxide is one of the more stable peroxides, contact withreducing agents and sources of heat, sparks, or open flamesmust be avoided. Organic per
17、oxides in general are irritating tothe skin, eyes, and mucous membranes. Avoid bodily contactand handle only in a well-ventilated area.10. Procedure10.1 Install the column in the chromatograph. The operatingconditions required to give the desired separation are given inTable 1. Set the helium flow t
18、o 10.0 mL/min and the oventemperature to 40C and allow sufficient time for the instru-ment to equilibrate as indicated by a stable baseline.10.2 Prepare test samples by transferring approximately0.2 g of di-tert-butyl peroxide into a flask or vial and addapproximately 10 mL of dodecane. Mix well.10.
19、3 Inject 0.5 L of the sample solution into the chromato-graph. A typical chromatogram is shown in Fig. 1 and Fig. 2.10.4 Determine the water content of the sample using a KarlFischer titration in accordance with Test Method E203.NOTE 1Water can be determined in samples of di-tert-butyl peroxideusing
20、 Test Method E203 without pretreatment with SO2if the sampletemperature is maintained below 20C during the titration. If the sampletemperature cannot be maintained below 20C, the sample must bepretreated by bubbling SO2through the sample for several minutes priorto titrating.11. Calculation11.1 Meas
21、ure the peak areas and calculate the total area bysumming the individual areas for all peaks except for that ofthe solvent peak, as follows:At5 A11 A21 A31 . 1 An(1)where:At= total area (excluding the solvent peak), andA1.n= area of individual component peaks.11.2 Calculate the area percent of di- t
22、ert-butyl peroxide asfollows:di2tert2butyl peroxide, area % 5AD100 2 W!At(2)where:AD= area of the di-tert-butyl peroxide peak,At= sum total of all component peaks (except solvent),andW = mass percent of water in the sample, as determined in10.4.The area percent of di-tert-butyl peroxide is assumed t
23、o beequal to the mass percent.11.3 If desired, calculate the mass percent of active oxygendue to di-tert-butyl peroxide as follows:active oxygen, mass % 5C 3 8.00073.11(3)where:C = di-tert-butyl peroxide, mass %.12. Report12.1 Report the purity of the di-tert-butyl peroxide to thenearest 0.01 %.13.
24、Precision and Bias13.1 Precision:13.1.1 Repeatability (Single Analyst)The coefficient ofvariation for a single determination has been estimated to be0.05 % relative at 18 degrees of freedom (df). The 95 % limitfor the difference between two such runs is 0.13 % relative.13.1.2 Laboratory Precision (W
25、ithin-Laboratory, Between-Days Variability, Formerly Called Repeatability)The coeffi-cient of variation of results (each the average of duplicates)obtained by the same analyst on different days has beenestimated to be 0.04 % relative at 9 df. The 95 % limit for thedifference between two such average
26、s is 0.10 % relative.13.1.3 Reproducibility (Multilaboratory)The coefficientof variation of results (each the average of duplicates) obtainedby analysts in different laboratories has been estimated to be0.24 % relative at 8 df. The 95 % limit for the differencebetween two such averages is 0.67 % rel
27、ative.NOTE 2The precision statements are based on an interlaboratorystudy3performed in 1995 on one sample of di-tert-butyl-peroxide.13.2 BiasThe bias of this test method has not beendetermined due to the unavailability of suitable referencematerials.14. Keywords14.1 active oxygen; di-tert-butyl pero
28、xide; gas chromatog-raphy; peroxides3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:E15-1044.TABLE 1 Operating Conditions Required to Give the DesiredSeparationDetector flame ionization (FID)Temperatures, CInjection port 150Dete
29、ctor 250Column temperature programInitial temperature, C 40Initial time, min 3Program rate, C/min 10Temperature 2, C 160Time 2, min 2Program rate, C/min 35Final temperature, C 240Final time, min 2Carrier gas heliumFlow rate, mL/min 10.0Injection volume, L 0.5E475 102FIG. 1 Typical ChromatogramFIG. 2
30、 Typical Chromatogram (Expanded View)E475 103SUMMARY OF CHANGESSubcommittee E15.02 has identified the location of selected changes to this standard since the last issue(E475-00(2005) that may impact the use of this standard.(1) Updated units of measure to comply with the InternationalSystem of Units
31、 (SI).(2) Added Summary of Changes section.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and
32、the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision
33、 of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shou
34、ldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 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 website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).E475 104
