ASTM D7884-19

Standard Test Method for Determination of 4-Carboxybenzaldehyde and <emph type="bdit" >p</emph>-Toluic Acid in Purified Terephthalic Acid by Reverse Phase High Performance Liquid Chromatography

SIGNIFICANCE AND USE
4.1 The presence of 4-CBA and p-TOL in PTA used for the production of polyester is undesirable because they can slow down the polymerization process and 4-CBA imparts coloration to the polymer due to thermal instability.  
4.2 Determining the amount of 4-CBA and p-TOL remaining from the manufacture of PTA 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.
SCOPE
1.1 This test method covers the determination of the 4-Carboxybenzaldehyde (4-CBA) and p-Toluic acid (p-TOL) in purified terephthalic acid (PTA) by reverse phase high performance liquid chromatography (HPLC). This method is applicable for 4-CBA from 2 to 500 mg/kg and for p-TOL from 10 to 500 mg/kg, respectively.  
1.2 In determining the conformance of the test results using this method to applicable specification, results shall be rounded off in accordance with the rounding-off method of Practice E29.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 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.  
1.5 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.

General Information

• Status: Historical
• Publication Date: 31-Oct-2019
• ICS: 71.080.40 - Organic acids
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.02 - Oxygenated Aromatics

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D7884 −19
Standard Test Method for
Determination of 4-Carboxybenzaldehyde and p-Toluic Acid
in Purified Terephthalic Acid by Reverse Phase High
1
Performance Liquid Chromatography
This standard is issued under the fixed designation D7884; 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* Procedures for Aromatic Hydrocarbons and Related Ma-
terials
1.1 This test method covers the determination of the
E29 Practice for Using Significant Digits in Test Data to
4-Carboxybenzaldehyde (4-CBA) and p-Toluic acid (p-TOL)
Determine Conformance with Specifications
in purified terephthalic acid (PTA) by reverse phase high
E682 Practice for Liquid Chromatography Terms and Rela-
performance liquid chromatography (HPLC). This method is
tionships
applicablefor4-CBAfrom2to500mg/kgandfor p-TOLfrom
E691 Practice for Conducting an Interlaboratory Study to
10 to 500 mg/kg, respectively.
Determine the Precision of a Test Method
1.2 In determining the conformance of the test results using
3
2.2 ISO Document:
thismethodtoapplicablespecification,resultsshallberounded
EN ISO 8213 Chemical products for industrial use—
off in accordance with the rounding-off method of Practice
Sampling techniques—Solid chemical products in the
E29.
form of particles varying from powders to coarse lumps
4
1.3 The values stated in SI units are to be regarded as
2.3 Other Document:
standard. No other units of measurement are included in this
OSHA Regulations, 29 CFR paragraphs 1910.1000 and
standard.
1910.1200
1.4 This standard does not purport to address all of the
3. Summary of Test Method
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 3.1 Reverse Phase HPLC Method—PTAsampleisdissolved
priate safety, health, and environmental practices and deter- in ammonium hydroxide solution, and a fixed volume of this
mine the applicability of regulatory limitations prior to use. solution is injected into a high performance liquid chromato-
1.5 This international standard was developed in accor- graph equipped with a UV detector.AC18 chemically bonded
dance with internationally recognized principles on standard- column is used to separate the impurities 4-CBA and p-TOL
ization established in the Decision on Principles for the from PTA. The external standard calibration is used for
Development of International Standards, Guides and Recom- quantification.
mendations issued by the World Trade Organization Technical
4. Significance and Use
Barriers to Trade (TBT) Committee.
4.1 The presence of 4-CBAand p-TOL in PTAused for the
2. Referenced Documents
production of polyester is undesirable because they can slow
2
down the polymerization process and 4-CBA imparts color-
2.1 ASTM Standards:
ation to the polymer due to thermal instability.
D1193 Specification for Reagent Water
D6809 Guide for Quality Control and Quality Assurance
4.2 Determining the amount of 4-CBA and p-TOL remain-
ing from the manufacture of PTA is often required. This test
method is suitable for setting specifications and for use as an
1
This test method is under the jurisdiction of ASTM Committee D16 on
internal quality control tool where these products are produced
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-
or are used.
bility of Subcommittee D16.02 on Oxygenated Aromatics.
Current edition approved Nov. 1, 2019. Published December 2019. Originally
approved in 2013. Last previous edition approved in 2013 as D7884 – 13. DOI:
3
10.1520/D7884-19. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 4th Floor, New York, NY 10036, http://www.ansi.org.
4
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
Standards volume information, refer to the standard’s Document Summary page on 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
the ASTM website. www.access.gpo.gov.
*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
1

---------------------- Page: 1 ----------------------
D7884−19
5
5. Apparatus Society, where such specifications are available. Other grades
may be used, provided it is first ascertained that the reagent is
5.1 High Performance Liquid Chromatograph (HPLC)—
of sufficiently high purity to permit its use without lessening
Any HPL
...

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.
Designation: D7884 − 13 D7884 − 19
Standard Test Method for
Determination of 4-Carboxybenzaldehyde and p-Toluic Acid
in Purified Terephthalic Acid by Reverse Phase High
1
Performance Liquid Chromatography
This standard is issued under the fixed designation D7884; 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 Scope*
1.1 This test method covers the determination of the 4-Carboxybenzaldehyde (4-CBA) and p-Toluic acid (p-TOL) in purified
terephthalic acid (PTA) by reverse phase high performance liquid chromatography (HPLC). This method is applicable for 4-CBA
from 2 to 500 mg/kg and for p-TOL from 10 to 500 mg/kg, respectively.
1.2 In determining the conformance of the test results using this method to applicable specification, results shall be rounded off
in accordance with the rounding-off method of Practice E29.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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
2.1 ASTM Standards:
D1193 Specification for Reagent Water
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
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E682 Practice for Liquid Chromatography Terms and Relationships
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3
2.2 ISO Document:
EN ISO 8213 Chemical products for industrial use—Sampling techniques—Solid chemical products in the form of particles
varying from powders to coarse lumps
4
2.3 Other Document:
OSHA Regulations, 29 CFR paragraphs 1910.1000 and 1910.1200
3. Summary of Test Method
3.1 Reverse Phase HPLC Method—PTA sample is dissolved in ammonium hydroxide solution, and a fixed volume of this
solution is injected into a high performance liquid chromatograph equipped with a UV detector. A C18 chemically bonded column
is used to separate the impurities 4-CBA and p-TOL from PTA. The external standard calibration is used for quantification.
1
This test method is under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons Aromatic, Industrial, Specialty and Related Chemicals and is the direct
responsibility of Subcommittee D16.02 on Oxygenated Aromatics.
Current edition approved Aug. 1, 2013Nov. 1, 2019. Published October 2013December 2019. Originally approved in 2013. Last previous edition approved in 2013 as
D7884 – 13. DOI: 10.1520/D7884-13.10.1520/D7884-19.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
4
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.
*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
1

---------------------- Page: 1 ----------------------
D7884 − 19
4. Significance and Use
4.1 The presence of 4-CBA and p-TOL in PTA used for the production of polyester is undesirable because they can slow down
the polymerization process and 4-CBA imparts coloration to the polymer due to thermal in
...