ASTM D1512-23

Standard Test Methods for Carbon Black—pH Value

SIGNIFICANCE AND USE
3.1 The pH level of a carbon black is known to affect the vulcanization of some rubber compounds.
SCOPE
1.1 These test methods, Test Method A—Boiling Slurry and Test Method B—Sonic Slurry, are used to indicate the pH of the carbon black surface by measuring the pH of water in contact with the carbon black.
Note 1: The pH of the carbon black is often used in this industry to indicate the relative acidity or alkalinity of carbon black and will be used in the remainder of these test methods to describe this property.
Note 2: Test Method A and Test Method B do not always give the same results.  
1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.  
1.3 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.  
1.4 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: 31-May-2023
• ICS: 83.040.20 - Rubber compounding ingredients
• Technical Committee: D24 - Carbon Black
• Drafting Committee: D24.31 - Non-Carbon Black Components of Carbon Black

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: D1512 − 23
Standard Test Methods for
1
Carbon Black—pH Value
This standard is issued under the fixed designation D1512; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope Standards in the Rubber and Carbon Black Manufacturing
Industries
1.1 These test methods, Test Method A—Boiling Slurry and
E70 Test Method for pH of Aqueous Solutions With the
Test Method B—Sonic Slurry, are used to indicate the pH of
Glass Electrode
the carbon black surface by measuring the pH of water in
contact with the carbon black.
3. Significance and Use
NOTE 1—The pH of the carbon black is often used in this industry to
3.1 The pH level of a carbon black is known to affect the
indicate the relative acidity or alkalinity of carbon black and will be used
vulcanization of some rubber compounds.
in the remainder of these test methods to describe this property.
NOTE 2—Test Method A and Test Method B do not always give the
TEST METHOD A—BOILING SLURRY
same results.
4. Apparatus
1.2 The values stated in SI units are to be regarded as the
standard. The values in parentheses are for information only.
4.1 pH Meter, (digital is recommended) having an accuracy
1.3 This standard does not purport to address all of the of 60.05 pH and equipped with a combination electrode and
safety concerns, if any, associated with its use. It is the RNC connector.
3
responsibility of the user of this standard to establish appro-
4.2 Container, stainless steel or copper, 125 cm or larger.
priate safety, health, and environmental practices and deter-
4.3 Hot Plate.
mine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accor- 4.4 High Speed Mill, Mixer or Mortar and Pestle.
dance with internationally recognized principles on standard-
4.5 Beakers, glass, appropriate beaker size to keep the ratio
ization established in the Decision on Principles for the
of Carbon Black to water 1:10, graduated with watch glasses.
Development of International Standards, Guides and Recom-
4.6 Magnetic Stir Plate.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4.7 Magnetic Stir Bars.
5. Reagents
2. Referenced Documents
2
5.1 Purity of Reagents—Reagent grade chemicals shall be
2.1 ASTM Standards:
used in all tests. Unless otherwise indicated, it is intended that
D1193 Specification for Reagent Water
all reagents shall conform to the specifications of the Commit-
D1799 Practice for Carbon Black—Sampling Packaged
tee on Analytical Reagents of the American Chemical Society,
Shipments
3
where such specifications are available. Other grades may be
D1900 Practice for Carbon Black—Sampling Bulk Ship-
used, provided it is first ascertained that the reagent is of
ments
sufficiently high purity to permit its use without lessening the
D4483 Practice for Evaluating Precision for Test Method
accuracy of the determination.
5.2 Purity of Water—Unless otherwise indicated, references
1
These test methods are under the jurisdiction of ASTM Committee D24 on to water shall be understood to mean reagent water as defined
Carbon Black and are the direct responsibility of Subcommittee D24.31 on
by Type 1 in Specification D1193.
Non-Carbon Black Components of Carbon Black.
Current edition approved June 1, 2023. Published July 2023. Originally approved
3
in 1975. Last previous edition approved in 2021 as D1512 – 21. DOI: 10.1520/ Reagent Chemicals, American Chemical Society Specifications, American
D1512-23. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or listed by the American Chemical Society, see Analar Standards for Laboratory
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Standards volume information, refer to the standard’s Document Summary page on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
the ASTM website. MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D1512 − 23
TABLE 1 Carbon Black Weight and Water Volumes
10. Precision and Bias
Carbon black Volume of water Beaker o
...

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: D1512 − 21 D1512 − 23
Standard Test Methods for
1
Carbon Black—pH Value
This standard is issued under the fixed designation D1512; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 These test methods, Test Method A—Boiling Slurry and Test Method B—Sonic Slurry, are used to indicate the pH of the
carbon black surface by measuring the pH of water in contact with the carbon black.
NOTE 1—The pH of the carbon black is often used in this industry to indicate the relative acidity or alkalinity of carbon black and will be used in the
remainder of these test methods to describe this property.
NOTE 2—Test Method A and Test Method B do not always give the same results.
1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.3 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.
1.4 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
D1799 Practice for Carbon Black—Sampling Packaged Shipments
D1900 Practice for Carbon Black—Sampling Bulk Shipments
D4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing Industries
E70 Test Method for pH of Aqueous Solutions With the Glass Electrode
3. Significance and Use
3.1 The pH level of a carbon black is known to affect the vulcanization of some rubber compounds.
1
These test methods are under the jurisdiction of ASTM Committee D24 on Carbon Black and are the direct responsibility of Subcommittee D24.31 on Non-Carbon Black
Components of Carbon Black.
Current edition approved May 1, 2021June 1, 2023. Published May 2021July 2023. Originally approved in 1975. Last previous edition approved in 20202021 as
D1512 – 15b (2020).D1512 – 21. DOI: 10.1520/D1512-21.10.1520/D1512-23.
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D1512 − 23
TEST METHOD A—BOILING SLURRY
4. Apparatus
4.1 pH Meter, (digital is recommended) having an accuracy of 60.05 pH and equipped with a combination electrode and RNC
connector.
3
4.2 Container, stainless steel or copper, 125 cm or larger.
4.3 Hot Plate.
4.4 High Speed Mill, Mixer or Mortar and Pestle.
3
4.5 Beakers, glass, 100 cmappropriate beaker size to keep the ratio of Carbon Black to water 1:10, graduated with watch glasses.
4.6 Magnetic Stir Plate.
4.7 Magnetic Stir Bars.
5. Reagents
5.1 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
3
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.
5.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean reagent water as defined by Type
1 in Specification D1193.
5.3 Distilled Water, high purity.
5.4 Buffer Solutions, pH of 4.00, 7.00, and 10.00.
5.5 Acetone, reagent grade.
6. Sampling
6.1 Samples shall be taken in accordance with Practices D1799 or D1900.
7. Calibration
7.1 Calibrate the pH meter using buffer solutions according to manufacturer’s instructions. Rinse
...