ASTM D7883-13

Standard Test Method for Determination of 4-Carboxybenzaldehyde and <emph type="bdit" >p</emph>-Toluic Acid in Purified Terephthalic Acid by Weak Anion Exchange 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 is also imparting 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 could be used as an internal quality control tool where these products are produced or are used.
SCOPE
1.1 This test method2 covers the determination of the 4-Carboxybenzaldehyde (4-CBA) and p-Toluic acid (p-TOL) in purified terephthalic acid (PTA) by weak anion exchange 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Jul-2013
• ICS: 71.080.40 - Organic acids
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.02 - Oxygenated Aromatics

Relations

• Referred By: ASTM D8062-23 - Standard Specification for Purified Terephthalic Acid (PTA) with Low <emph type="ital" >p</emph>-Toluic Acid
• Effective Date: 01-Aug-2013
• Referred By: ASTM D7976-14(2020) - Standard Specification for Purified Terephthalic Acid (PTA)
• Effective Date: 01-Aug-2013

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D7883 −13
Standard Test Method for
Determination of 4-Carboxybenzaldehyde and p-Toluic Acid
in Purified Terephthalic Acid by Weak Anion Exchange High
1
Performance Liquid Chromatography
This standard is issued under the fixed designation D7883; 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 E29 Practice for Using Significant Digits in Test Data to
2 Determine Conformance with Specifications
1.1 This test method covers the determination of the
E177 Practice for Use of the Terms Precision and Bias in
4-Carboxybenzaldehyde (4-CBA) and p-Toluic acid (p-TOL)
ASTM Test Methods
in purified terephthalic acid (PTA) by weak anion exchange
E682 Practice for Liquid Chromatography Terms and Rela-
high performance liquid chromatography (HPLC). This
tionships
method is applicable for 4-CBA from 2 to 500 mg/kg and for
E691 Practice for Conducting an Interlaboratory Study to
p-TOL from 10 to 500 mg/kg, respectively.
Determine the Precision of a Test Method
1.2 In determining the conformance of the test results using
4
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
5
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 Weak Anion Exchange HPLC Method—PTA sample is
priate safety and health practices and determine the applica- dissolved in ammonium hydroxide solution. After pH
bility of regulatory limitations prior to use. adjustment, a fixed volume of this solution is injected into a
high performance liquid chromatograph equipped with a UV
2. Referenced Documents
detector. An anion-exchange column is used to separate the
3
2.1 ASTM Standards:
impurities 4-CBAand p-TOLfrom PTA.The external standard
D1193 Specification for Reagent Water calibration is used for quantification.
D4790 Terminology ofAromatic Hydrocarbons and Related
4. Significance and Use
Chemicals
D6809 Guide for Quality Control and Quality Assurance
4.1 The presence of 4-CBAand p-TOL in PTAused for the
Procedures for Aromatic Hydrocarbons and Related Ma-
production of polyester is undesirable because they can slow
terials
down the polymerization process, and 4-CBAis also imparting
coloration to the polymer due to thermal instability.
1
This test method is under the jurisdiction of ASTM Committee D16 on
4.2 Determining the amount of 4-CBA and p-TOL remain-
Aromatic Hydrocarbons and Related Chemicals and is the direct responsibility of
ing from the manufacture of PTA is often required. This test
Subcommittee D16.02 on Oxygenated Aromatics.
Current edition approved Aug. 1, 2013. Published October 2013. DOI: 10.1520/
method is suitable for setting specifications and could be used
D7883-13.
as an internal quality control tool where these products are
2
This standard is based on SH/T 1612.7-1995 Purified terephthalic acid for
produced or are used.
industrial use—determination of p-Toluic Acid, 4-Carboxybenzaldehyde-HPLC,
copyright SINOPEC, 22 Chaoyangmen North Street, Chaoyang District, Beijing,
China 100728. A copy of SH/T 1612.7-1995 may be obtained from China
4
Petrochemical Press, www.sinopec-press.com. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 4th Floor, New York, NY 10036, http://www.ansi.org.
5
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.
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D7883−13
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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
...