ASTM D5713-23

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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: D5713 − 14 (Reapproved 2018) D5713 − 23
Standard Test Method for
Analysis of High Purity Benzene for Cyclohexane Feedstock
by Capillary Gas Chromatography
This standard is issued under the fixed designation D5713; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Editorial corrections made in Footnote 1 and 8.1 in June 2018.
1. Scope Scope*
1.1 This test method covers the determination of specific impurities in, and the purity of benzene for cyclohexane feedstock by
gas chromatography.
1.2 This test method has been found applicable to benzene in the range from 9999 % to 100 % purity and to impurities at
concentrations of 22 mg ⁄kg to 10 000 mg/kg.mg ⁄kg. The limit of detection (LOD) is 2 mg/kg for an impurity and the limit of
quantitation (LOQ) is 6 mg/kg for an impurity.
1.3 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off
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 any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. For specific hazard statements, see 7.2 and Section 8.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D3437 Practice for Sampling and Handling Liquid Cyclic Products
D4790 Terminology of Aromatic Hydrocarbons and Related Chemicals
D6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E260 Practice for Packed Column Gas Chromatography
E355 Practice for Gas Chromatography Terms and Relationships
This test method is under the jurisdiction of ASTM Committee D16 on Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsibility of
Subcommittee D16.01 on Benzene, Toluene, Xylenes, Cyclohexane and Their Derivatives.
Current edition approved June 1, 2018May 1, 2023. Published June 2018May 2023. Originally approved in 1995. Last previous edition approved in 20142018 as
ɛ1
D5713 – 14.D5713 – 14 (2018) . DOI: 10.1520/D5713-14R18E01.10.1520/D5713-23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*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
D5713 − 23
E1510 Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs
2.2 Other Document:
OSHA Regulations, 29 CFR paragraphs 1910.1000 and 1910.1200
3. Terminology
3.1 Definitions:
3.1.1 See Terminology D4790 for definition of terms used in this test method.
4. Summary of Test Method
4.1 In this test method, the chromatogram peak area for each impurity is compared to the peak area of the internal standard
(n-octane or other suitable known) added to the sample. From the response factor of toluene relative to that of the internal standard,
and using a response factor of 1.00 for nonaromatic impurities and the amount of internal standard added, the concentrations of
the impurities are calculated. The benzene content is obtained by subtracting the total amount of all impurities from 100.00.
5. Significance and Use
5.1 This test method is useful for benzene purity on the basis of impurities normally present in benzene and may be used for final
product inspections and process control.
5.2 This test method will detect the following impurities: toluene, methylcyclopentane, n-hexane, 2-methylhexane, cyclohexane,
cyclopentane, 2-methylpentane, 2,3-dimethylpentane, 3-methylhexane, n-heptane, methylcyclohexane, ethylcyclopentane, 2,4-
dimethylhexane, trimethylpentane, and others where specific impurity standards are available. Absolute purity cannot be accurately
determined if unknown impurities are present.
6. Apparatus
6.1 Gas Chromatograph—Any gas chromatograph having a temperature programmable oven, flame ionization detector and a
splitter injector suitable for use with a fused silica capillary column may be used, provided the system has sufficient sensitivity that
will give a minimum peak height of 3 times the background noise for 2 mg/kg of an impurity.
6.2 Column—Fused silica capillary columns have been found to be satisfactory. An example is 50 m of 0.20-mm0.20 mm inside
diameter fused silica capillary internally coated to a film thickness of 0.50 μm with polydimethylsiloxane (see Table 1 for suggested
instrument parameters). Other columns may be used after it has been established that such a column is capable of separating all
major impurities (for example, compounds listed in 5.2) and the internal standard from the benzene under operating conditions
TABLE 1 Recommended Operating Conditions
Carrier gas hydrogen
Linear velocity at 40°C, cm/s 40
Linear velocity at 40 °C, cm ⁄s 40
Detector flame ionization
Detector temperature, °C 250°C
Detector temperature, °C 250 °C
Injection port temperature, °C 250°C
Injection port temperature, °C 250 °C
Split ratio 40:1
Split flow, mL/min 60
Column 50 m by 0.20 mm ID by 0.5 μm
bonded polydimethylsiloxane
capillary column
Initial column temperature, °C 40
Initial time, min 17
Programming rate 10°C/min
Programming rate 10 °C ⁄min
Final temperature, °C 250°C
Final temperature, °C 250 °C
Final time, min 10
Sample size, μL 1.2
Available 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.
D5713 − 23
TABLE 2 Summary of Precision Data
Average
Intermediate
Component Concentration Reproducibility
Precision
mg/kg
Benzene (weight %) 99.96 0.006 0.022
99.97 0.007 0.020
99.96 0.008 0.025
Methylcyclopentane 104 8.3 27.9
43 12.2 19.4
54 2.5 15.1
Toluene 64 5.1 22.0
63 3.0 16.6
28 1.8 9.1
Methylcyclohexane 132 7.4 34.8
43 1.4 5.4
79 3.2 17.0
Methylcyclohexane + 196 7.9 54.9
Toluene 106 12.9 33.6
106 4.4 20.4
n-Hexane 4 2.2 3.7
3 1.5 2.2
2 1.8 2.5
n-Heptane 6 2.7 11.1
16 1.5 5.6
15 4.0 23.4
Ethylcyclopentane 7 1.8 3.7
6 1.9 11.0
11 1.5 6.1
Total Other Impurities 99 22.5 163.0
107 44.6 190.6
185 55.5 233.0
appropriate for the column. The column must give satisfactory resolution (distance from the valley between the peaks is not greater
than 50 % of the peak heights of the impurity) of cyclohexane from benzene as well as other impurity peaks. A poorly resolved
peak, such as cyclohexane, will often require a tangent skim from the neighboring peak.
6.3 Electronic Integration, with tangent skim capabilities is recommended.
6.4 Vial.
6.5 Microsyringes, assorted volumes.
6.6 Injector, the specimen must be precisely and repeatedly injected into the gas chromatograph. An automatic sample injection
device is highly recommended. Manual injection can be employed if the precision stated in Table 2 can be reliably and consistently
satisfied.
7. Reagents and Materials
7.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated it is intended that all
reagents shall conform to the specifications of the Committee on Analytical reagents of the American Chemical Society, where such
specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity
to permit its use without l
...