ASTM D4471-22

Standard Test Method for Pyridine Bases in Cresylic Acid by Direct Titration

SIGNIFICANCE AND USE
5.1 The pyridine base content of cresylic acids is important in certain applications. This test method may be used as a tool for quality control and specification purposes by producers and users.
SCOPE
1.1 This test method covers the determination of pyridine and other basic nitrogen impurities in crude and refined cresylic acids streams, including mixtures.  
1.2 This test method is applicable for pyridine base levels of 0.001 % to 0.5 %.  
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 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2022
• ICS: 71.080.30 - Organic nitrogen compounds
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.02 - Oxygenated Aromatics

Relations

• Refers: ASTM D3852-20 - Standard Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• Effective Date: 01-Jun-2020
• Refers: ASTM D6809-02(2016) - Standard Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
• Effective Date: 01-Nov-2016
• Refers: ASTM D3852-16 - Standard Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• Effective Date: 01-Jun-2016
• Refers: ASTM D4790-14 - Standard Terminology of Aromatic Hydrocarbons and Related Chemicals
• Effective Date: 01-Jul-2014
• Refers: ASTM D3852-07(2012) - Standard Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• Effective Date: 01-Jun-2012
• Refers: ASTM D4790-11 - Standard Terminology of Aromatic Hydrocarbons and Related Chemicals
• Effective Date: 01-Feb-2011
• Refers: ASTM E29-08 - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 01-Oct-2008
• Refers: ASTM D4790-07 - Standard Terminology of Aromatic Hydrocarbons and Related Chemicals
• Effective Date: 15-Jul-2007
• Refers: ASTM D6809-02(2007) - Standard Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
• Effective Date: 01-Jun-2007
• Refers: ASTM D3852-07 - Standard Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• Effective Date: 01-Jan-2007
• Refers: ASTM E29-06b - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 15-Nov-2006
• Refers: ASTM E29-06a - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 15-Sep-2006
• Refers: ASTM D3852-06 - Standard Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• Effective Date: 01-Jul-2006
• Refers: ASTM E29-06 - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 01-May-2006
• Refers: ASTM E29-04 - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 01-Dec-2004

Overview

ASTM D4471-22: Standard Test Method for Pyridine Bases in Cresylic Acid by Direct Titration is an internationally recognized standard developed by ASTM International. This test method provides a reliable procedure for determining pyridine and other basic nitrogen impurities in both crude and refined cresylic acid streams, including various mixtures. The standard plays a vital role in quality control and specification verification for cresylic acid producers and users, helping to ensure product purity for industrial and chemical applications.

The test covers pyridine base content detection in the range of 0.001% to 0.5% by weight, supporting the precise monitoring of nitrogenous contaminants. Compliance with this method aids organizations in meeting industry quality and regulatory requirements.

Key Topics

• Scope and Applicability
  • Determines pyridine and basic nitrogen impurities in cresylic acids (crude, refined, or mixtures)
  • Applicable to pyridine base levels from 0.001% to 0.5%
  • Results are rounded off according to Practice E29
  • SI units are used exclusively as standard
• Test Methodology
  • Employs a direct, nonaqueous titration using perchloric acid in acetic acid as the titrant
  • Endpoints may be identified by potentiometric means or indicator (quinaldine red), making it suitable for both highly colored and lighter colored samples
  • All basic components detected are reported as percent pyridine
• Significance and Use
  • Essential for quality control and specification processes in the manufacturing and use of cresylic acids
  • Helps identify contamination or improper levels of pyridine base in industrial feedstocks or end-products
  • Supports regulatory compliance for safety, health, and environmental standards
• Precision and Quality Assurance
  • Encourages the use of internal laboratory quality control practices and interlaboratory testing for result validation
  • Precision is defined for within-laboratory and between-laboratory differences to ensure confidence and comparability of results

Applications

The ASTM D4471-22 standard is widely applied within the chemical and petrochemical industries, particularly in the production and processing of cresylic acids. Key applications include:

• Quality Control: Ensuring that cresylic acid batches meet required pyridine base limits before shipping or further chemical processing.
• Specification Verification: Supporting both buyers and sellers in confirming that chemical products meet the contractual or regulatory specifications.
• Process Monitoring: Tracking changes within production streams to promptly identify process drifts or contamination.
• Regulatory Compliance: Providing standardized data to demonstrate conformance with health, safety, and environmental regulations governing cresylic acids and nitrogen base content.

Proper application of this method helps prevent downstream processing issues and safeguards the integrity and performance of cresylic acid-based products used in industries such as resins, solvents, and specialty chemicals.

Related Standards

Organizations using ASTM D4471-22 may also find the following standards relevant:

• ASTM D3852: Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
• ASTM D4790: Terminology of Aromatic Hydrocarbons and Related Chemicals
• ASTM D6809: Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
• ASTM E29: Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

These related standards support accurate sampling, correct terminology, effective QA/QC procedures, and proper data reporting-further enhancing the reliability and regulatory acceptance of results obtained using ASTM D4471-22.

Keywords: pyridine bases, cresylic acid, direct titration, nitrogen impurities, quality control, ASTM standards, phenol, cresols, tar acids.

Standards Content (Sample)

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.
Designation: D4471 − 22
Standard Test Method for
Pyridine Bases in Cresylic Acid by Direct Titration
This standard is issued under the fixed designation D4471; 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* D6809 Guide for Quality Control and Quality Assurance
Procedures for Aromatic Hydrocarbons and Related Ma-
1.1 This test method covers the determination of pyridine
terials
and other basic nitrogen impurities in crude and refined
E29 Practice for Using Significant Digits in Test Data to
cresylic acids streams, including mixtures.
Determine Conformance with Specifications
1.2 Thistestmethodisapplicableforpyridinebaselevelsof
2.2 Other Document:
0.001 % to 0.5 %.
OSHA Regulations, 29 CFR paragraphs 1910.1000 and
1.3 In determining the conformance of the test results using 1910.1200 Air Contaminates – Table of Exposure Limits
this method to applicable specifications, results shall be
and Hazard Communication
rounded off in accordance with the rounding-off method of
3. Terminology
Practice E29.
3.1 For definitions of terms used in this test method see
1.4 The values stated in SI units are to be regarded as
Terminology D4790.
standard. No other units of measurement are included in this
standard.
4. Summary of Test Method
1.5 This standard does not purport to address all of the
4.1 This test method is a direct, nonaqueous titration tech-
safety concerns, if any, associated with its use. It is the
nique utilizing perchloric acid in acetic acid as titrant and the
responsibility of the user of this standard to establish appro-
cresylic acid itself as titration solvent. Endpoints may be
priate safety, health, and environmental practices and deter-
established potentiometrically as well as by indicator so that
mine the applicability of regulatory limitations prior to use.
the method is applicable to highly colored as well as lighter
For specific hazard statements, see Section 8.
colored materials. This test method will detect basic compo-
1.6 This international standard was developed in accor-
nents other than pyridine bases should they be present. All
dance with internationally recognized principles on standard-
basic compounds detected by this procedure are calculated and
ization established in the Decision on Principles for the
expressed as percent pyridine.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
5. Significance and Use
Barriers to Trade (TBT) Committee.
5.1 The pyridine base content of cresylic acids is important
in certain applications. This test method may be used as a tool
2. Referenced Documents
for quality control and specification purposes by producers and
2.1 ASTM Standards:
users.
D3852 Practice for Sampling and Handling Phenol, Cresols,
and Cresylic Acid
6. Apparatus
D4790 Terminology ofAromatic Hydrocarbons and Related
6.1 Titrimeter or pH meter, equipped with half cell or
Chemicals
combination glass pH and Ag/AgCl reference electrodes. The
pair of electrodes shall be mounted to extend well below the
liquid level. Storage in water between titrations is essential
This test method is under the jurisdiction of ASTM Committee D16 on
because prolonged immersion in nonaqueous medium signifi-
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-
cantly deadens response.
bility of Subcommittee D16.02 on Oxygenated Aromatics.
Current edition approved May 1, 2022. Published June 2022. Originally
6.2 Buret, 50-mL capacity. For low pyridine base concen-
approved in 1985. Last previous edition approved in 2018 as D4471 – 18. DOI:
trations: 10 mL burette that reads to 0.05 mL.
10.1520/D4471-22.
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 AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
the ASTM website. 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.
*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
D4471 − 22
6.3 Magnetic Stirrer, with TFE-fluorocarbon or glass cov- 10.2 Thespecimenistitratedwithperchloricacidtitrantand
ered stirring bar. the endpoint determined by either of the following methods:
10.2.1 Indicator—Afew drops of quinaldine red indicator is
6.4 Autotitration Equipment may be used if available.
added to the solution. The titration is terminated when the red
color disappears and the color of the sample returns to its
7. Reagents
original hue.
7.1 Purity of Reagents—Reagent grade chemicals shall be
10.2.2 Potentiometric—The electrodes are inserted into the
used in all tests. Unless otherwise indicated, it is intended that
specimen and the observed potentials are plotted as a function
all reagents shall conform to the specifications of the Commit-
of the titrant volume consumed. The point where∆E/∆V is the
tee onAnalytical Reagents of theAmerican Chemical Society,
greatest is taken as the endpoint.
where such specifications are available. Other grades may be
10.3 Repeat 10.1 through 10.2, but with no specimen to
used, provided it is first ascertained that the reagent is of
obtain a reagent blank when titration solvent is used.
sufficiently high purity to permit its use without lessening the
accuracy of the determination.
11. Calculation
7.2 Perchloric Acid Titrant (0.02 N in glacial acetic acid)—
11.1 Results are calculated as weight percent pyridine, P,as
Add 1.8 mL of 70 % perchloric acid (HClO ) to 1 L of glacial
follows:
acetic acid and mix well. To standardize, weigh accurately
0.0800 to 0.0950 g of primary standard potassium acid
7.91 3 N 3 V 2 V
~ !
S B
P 5
phthalate in glacial acetic acid and titrate potentiometrically or
W
to the indicator endpoint, as described in 10.2. Calculate the
where:
normality, N, of
...

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: D4471 − 18 D4471 − 22
Standard Test Method for
Pyridine Bases in Cresylic Acid by Direct Titration
This standard is issued under the fixed designation D4471; 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 pyridine and other basic nitrogen impurities in crude and refined cresylic acids
streams, including mixtures.
1.2 This test method is applicable for pyridine base levels of 0.001 % to 0.5 %.
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 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:
D3852 Practice for Sampling and Handling Phenol, Cresols, and Cresylic Acid
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
2.2 Other Document:
OSHA Regulations, 29 CFR paragraphs 1910.1000 and 1910.1200 paragraphs 1910.1000 and 1910.1200Air Contaminates –
Table of Exposure Limits and Hazard Communication
3. Terminology
3.1 For definitions of terms used in this test method see Terminology D4790.
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 D16.02 on Oxygenated Aromatics.
Current edition approved June 1, 2018May 1, 2022. Published July 2018June 2022. Originally approved in 1985. Last previous edition approved in 20102018 as
D4471 – 10.D4471 – 18. DOI: 10.1520/D4471-18.10.1520/D4471-22.
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.
Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.
*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
D4471 − 22
4. Summary of Test Method
4.1 This test method is a direct, nonaqueous titration technique utilizing perchloric acid in acetic acid as titrant and the cresylic
acid itself as titration solvent. Endpoints may be established potentiometrically as well as by indicator so that the method is
applicable to highly colored as well as lighter colored materials. This test method will detect basic components other than pyridine
bases should they be present. All basic compounds detected by this procedure are calculated and expressed as percent pyridine.
5. Significance and Use
5.1 The pyridine base content of cresylic acids is important in certain applications. This test method may be used as a tool for
quality control and specification purposes by producers and users.
6. Apparatus
6.1 Titrimeter or pH meter, equipped with half cell or combination glass pH and Ag/AgCl reference electrodes. The pair of
electrodes shall be mounted to extend well below the liquid level. Storage in water between titrations is essential because prolonged
immersion in nonaqueous medium significantly deadens response.
6.2 Buret, 50-mL capacity. For low pyridine base concentrations: 10 mL burette that reads to 0.05 mL.
6.3 Magnetic Stirrer, with TFE-fluorocarbon or glass covered stirring bar.
6.4 Autotitration Equipment may be used if available.
7. Reagents
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 lessening the accuracy of the determination.
7.2 Perchloric Acid Titrant (0.02 N in glacial acetic acid)—Add 1.8 mL of 70 % perchloric acid (HClO ) to 1 L 1 L of glacial
acetic acid and mix well. To standardize, weigh accurately 0.0800 to 0.0950 g of primary standard potassium acid phthalate in
glacial acetic acid and titrate potentiometrically or to the indicator endpoint, as described in 10.2. Calculate the normality, N, of
the perchloric acid solution as follows:
W
N 5
V 30.2041
where:
W = weight of potassium acid phthalate, g, and
V = volume of perchloric acid titrant consumed, mL.
7.3 Potassium Acid Phthalate (KH C H O ), primary standard—Dry for 2 h at 110°C.110 °C.
8 8 4
7.4 Quinaldine Red Indicator Solution—Dissolve 0.2 g of quinaldine red indicator in 100 g of glacial acetic acid.
7.5 Titration Solvent—Glacial acetic acid (CH CO H) may be used as an additional titration solvent in order to decrease the
3 2
viscosity of a particular sample or to keep it from freezing.
Reagent Chemicals, American Chemical Society Specifications,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
Labor
...