ASTM D5917-24 用气相色谱法和外标法测定单环芳烃中痕量杂质的标准试验方法

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Designation: D5917 −24
Standard Test Method for
Trace Impurities in Monocyclic Aromatic Hydrocarbons by
Gas Chromatography and External Calibration
1
This standard is issued under the ﬁxed designation D5917; 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.
1. Scope*
1.1 This test method covers the determination of the total
nonaromatic hydrocarbons and trace monocyclic aromatic
hydrocarbons in toluene, mixed xylenes, and p-xylene by gas
chromatography. The purity of toluene, mixed xylenes, or
p-xylene can also be calculated. Calibration of the gas chro-
matographic system is done by the external standard calibra-
tion technique.
1.2 Total aliphatic hydrocarbons containing 1 through 10
carbon atoms (methane through decanes) can be detected by
this test method at concentrations ranging from 0.001 mass %
to 2.500 mass %.
1.2.1 A small amount of benzene in mixed xylenes or
p-xylenes may not be distinguished from the nonaromatics and
the concentrations are determined as a composite (see 6.1).
1.3 Monocyclic aromatic hydrocarbon impurities containing
6 through 10 carbon atoms (benzene through C
10
aromatics)
can be detected by this test method at individual concentrations
ranging from 0.001 mass % to 1.000 mass %.
1.4 In determining the conformance of the test results to
applicable speciﬁcations, results shall be rounded off in accor-
dance with the rounding-off method of Practice E29.
1.5 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
standard.
1.6 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 appro-
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
For speciﬁc hazard statement, see Section 9.
1.7 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
2
D841 Speciﬁcation for Nitration Grade Toluene
D3437 Practice for Sampling and Handling Liquid Cyclic
Products
D4052 Test Method for Density, Relative Density, and API
Gravity of Liquids by Digital Density Meter
D4307 Practice for Preparation of Liquid Blends for Use as
Analytical Standards
D4790 Terminology of Aromatic Hydrocarbons and Related
Chemicals
D5136 Speciﬁcation for High Purity p-Xylene
D5211 Speciﬁcation for Xylenes for p-Xylene Feedstock
D6809 Guide for Quality Control and Quality Assurance
Procedures for Aromatic Hydrocarbons and Related Ma-
terials
D7504 Test Method for Trace Impurities in Monocyclic
Aromatic Hydrocarbons by Gas Chromatography and
Effective Carbon Number
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 Relation-
ships
E691 Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method
E1510 Practice for Installing Fused Silica Open Tubular
Capillary Columns in Gas Chromatographs
1
This test method is under the jurisdiction of ASTM Committee D16 on
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-
bility of Subcommittee D16.01 on Benzene, Toluene, Xylenes, Cyclohexane and
Their Derivatives.
Current edition approved Oct. 1, 2024. Published November 2024. Originally
approved in 1996. Last previous edition approved in 2019 as D5917 – 15 (2019).
DOI: 10.1520/D5917-24.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at www.astm.org/contact. 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
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.
1

2.2 Other Document:

OSHA Regulations, 29 CFR paragraphs 1910.1000 and

1910.1200

3. Terminology

3.1 See Terminology D4790 for deﬁnitions of terms used in

this test method.

3.2 Mixed xylenes are a mixture of C

aromatics including

m-xylene, o-xylene, and p-xylene. Industry convention in-

cludes ethylbenzene as a ‘mixed xylene’ though ethylbenzene

is not technically a xylene. Styrene is excluded.

4. Summary of Test Method

4.1 A repeatable volume of the specimen to be analyzed is

precisely injected into a gas chromatograph equipped with a

ﬂame ionization detector (FID). The peak area of each impurity

is measured. Concentration of each impurity is determined

from the linear calibration curve of peak area versus concen-

tration. Purity by gas chromatography (GC) is calculated by

subtracting the sum of the impurities found from 100.00.

Results are reported in mass percent.

5. Signiﬁcance and Use

5.1 Determining the type and amount of hydrocarbon im-

purities remaining from the manufacture of toluene, mixed

xylenes, and p-xylenes used as chemical intermediates and

solvents is often required. This test method is suitable for

setting speciﬁcations and for use as an internal quality control

tool where these products are produced or are used. Typical

impurities are: alkanes containing 1 to 10 carbons atoms,

benzene, toluene, ethylbenzene (EB), xylenes, and aromatic

hydrocarbons containing nine carbon atoms.

5.2 Purity is commonly reported by subtracting the deter-

mined expected impurities from 100.00. However, a gas

chromatographic analysis cannot determine absolute purity if

unknown or undetected components are contained within the

material being examined.

6. Interferences

6.1 In some cases for mixed xylenes and p-xylene, it may be

difficult to resolve benzene from the nonaromatic hydrocar-

bons. Therefore the concentrations are determined as a com-

posite. In the event that the benzene concentration must be

determined, an alternate method such as Test Method D7504

must be selected to ensure an accurate assessment of the

benzene concentration.

6.2 Complete separation of ethylbenzene and m-xylene

from p-xylene is difficult and can be considered adequate if the

distance from baseline to valley between peaks is not greater

than 50 % of the peak height of the impurity.

7. Apparatus

7.1 Gas Chromatograph—Any instrument having a ﬂame

ionization detector that can be operated at the conditions given

in Table 1. The system shall have sufficient sensitivity to obtain

aminimum peak height response for 0.001 mass % impurity of

twice the height of the background noise.

7.2 Columns—The choice of column is based on resolution

requirements. Any column may be used that is capable of

resolving all signiﬁcant impurities from the major component.

The column and conditions described in Table 1 have been

used successfully and shall be used as a referee in cases of

dispute.

7.2.1 Contamination on the front end of the column can be

minimized by baking out the column on a periodic basis or

eliminated by cutting off a few inches from the front end.

7.2.2 It is helpful to dedicate GC’s for each high purity

product and other GCs for samples with signiﬁcant impurities.

7.3 Chromatographic data systems are preferred but elec-

tronic integration may be used if the user can demonstrate that

the results are consistent with the precision statement.

7.4 Injector—An automatic sample injection device is re-

quired.

7.5 Volumetric Flask, 100 mL capacity.

7.6 Syringe, 100 µL.

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.

TABLE 1 Recommended Operating Conditions

Inlet Split

Temperature, °C 270

Column:

Tubing fused silica

Length, m 60

Internal diameter, mm 0.32

Stationary phase crosslinked polyethylene glycol

Film thickness, µm 0.25

Column temperature program

Initial temperature, °C 60

Initial time, min 10

Programming rate, °C/min 5

Final, °C 150

Time 2, min 10

Carrier gas Helium or Hydrogen

Linear velocity, cm/s at 145 °C 20 Helium or 45 Hydrogen

Split ratio 100:1

Sample size, µL 1.0

Detector: ﬂame ionization

Temperature, °C 300

Analysis time, min 30

D5917 − 24

8. Reagents

8.1 Purity of Reagent—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 Commit-

tee on Analytical Reagents of the American Chemical Society,

where such speciﬁcations are available.

8.2 Carrier Gas—Chromatographic grade helium or

hydrogen, 99.999 % is recommended. Purify carrier, fuel and

makeup gases by adding traps to reduce the concentration of

any remaining oxygen, water, and hydrocarbons. Purify air by

adding traps to reduce the concentration of any remaining

hydrocarbons and water.

8.3 Air, Chromatographic grade, containing less than

0.1 ppm THC.

8.4 High Purity p-Xylene, 99.999 mass % or greater purity.

8.4.1 Most p-xylene is available commercially at a purity

less than 99.9 % and can be puriﬁed by recrystallization. To

prepare 1.9 L of high purity p-xylene, begin with approxi-

mately 3.8 L of material and cool in a ﬂammable storage

freezer at −10 °C 65 °C until approximately

⁄

of the

p-xylene has frozen. This should require about 5 h. Remove the

sample and decant the liquid portion. The solid portion is the

puriﬁed p-xylene. Allow the p-xylene to thaw and repeat the

crystallization procedure on the remaining sample until the

p-xylene is free of contamination as indicated by gas chroma-

tography.

8.5 Pure compounds for calibration, shall include n-nonane,

benzene, toluene, ethylbenzene, o-xylene, m-xylene, and

cumene. If applicable, the calibration may include paradieth-

ylbenzene (PDEB). The purity of all reagents should be >99

mass %. If the purity is less than 99 %, the concentration and

identiﬁcation of impurities must be known so that the compo-

sition of the standard can be adjusted for the presence of the

impurities.

9. Hazards

9.1 Consult current OSHA regulations, supplier’s Safety

Data Sheets, and local regulations for all materials used in this

test method.

10. Sampling

10.1 Sample the material in accordance with Practice

D3437.

11. Preparation of Apparatus

11.1 Follow manufacturer’s instructions for mounting and

conditioning the column into the chromatograph and adjusting

the instrument to the conditions described in Table 1, allowing

sufficient time for the equipment to reach equilibrium. See

Practices E260,E355, and E1510 for additional information on

gas chromatography practices and terminology.

12. Calibration

12.1 Prepare a synthetic mixture of high purity p-xylene

containing impurities at concentrations representative of those

expected in the samples to be analyzed. The volume of each

hydrocarbon impurity must be measured to the nearest 1 µL

and all liquid reference compounds must be brought to the

same temperature before mixing. Refer to Table 2 for an

example of a calibration blend. n-Nonane will represent the

nonaromatic fraction, o-xylene the o-xylene fraction, m-xylene

the m-xylene fraction. Cumene will represent the aromatic

hydrocarbons containing nine carbon atoms or greater, with

exception of PDEB. If PDEB is included in the calibration,

PDEB will represent PDEB.

12.1.1 Prior to preparing the calibration standard, all refer-

ence compounds and any samples to be analyzed must be

brought to the same temperature, preferably ambient or 20 °C.

12.2 Using the exact volumes and densities in Table 2,

calculate the mass % concentration for each impurity in the

calibration blend as follows:

5100 D

(1)

where:

= density of impurity ifrom Table 2,

= volume of impurity i, mL,

ACS Reagent Chemicals, Speciﬁcations and Procedures for Reagents and

Standard-Grade Reference Materials, American Chemical Society, Washington,

DC. For suggestions on the testing of reagents not listed by the American Chemical

Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,

U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-

copeial Convention, Inc. (USPC), Rockville, MD.

TABLE 2 Preparation of Calibration Blend

Compound Density

Recommended

Vol, µL

Resulting Concentration (including

PDEB)

Resulting Concentration (excluding

PDEB)

volume % mass % volume % mass %

p-Xylene 0.861 99.60-99.62 ml 99.60 99.60 99.62 99.62

Benzene 0.879 20 0.020 0.020 0.020 0.020

Toluene 0.867 20 0.020 0.020 0.020 0.020

Ethylbenzene 0.867 100 0.100 0.100 0.100 0.100

o-Xylene 0.880 100 0.100 0.102 0.100 0.102

Cumene 0.862 20 0.020 0.020 0.020 0.020

n-Nonane 0.718 20 0.020 0.017 0.020 0.017

m-Xylene 0.864 100 0.100 0.101 0.100 0.101

PDEB 0.866 20 0.020 0.020 n/a n/a

Density at 20 °C. Values obtained from “Physical Constants of Hydrocarbons C

to C

;” ASTM Publication DS 4A, 1971.

D5917 − 24

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标签： #标准试验 #试验方法 #标准试验方法

摘要：

本文档详细介绍了ASTM D5917-24标准，即采用气相色谱法与外部标准校准法，准确测定单环芳烃（如苯、甲苯、二甲苯等）中痕量杂质的标准试验方法。该标准适用于分析纯芳烃产品中微量烃类及其他杂质成分，为质量控制、产品纯度验证及科研检测提供可靠依据。通过本方法，实验室可实现对非芳烃、特定取代芳烃等杂质的高灵敏度定性与定量分析，确保结果符合国际规范。文档涵盖了试验原理、仪器配置、样品处理步骤、定量计算方式以及精密度与偏差要求，是石化、化工及环境监测领域专业人员优化检测流程、提升数据可重复性的重要参考

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