ASTM D7633-13(2022)

Standard Test Method for Carbon Black-Carbon Content

SIGNIFICANCE AND USE
4.1 The total carbon content of a carbon black is a requirement for the calculation and reporting of carbon dioxide emissions. It can also be used in calculations to estimate yield of the process.
SCOPE
1.1 This test method covers the instrumental determination of carbon content in a carbon black sample. Values obtained represent the total carbon content.  
1.2 The method is applicable to tread, carcass and specialty type carbon blacks obtained from partial combustion or thermal decomposition processes, which typically contain 95 to 100 % carbon.  
1.3 The results of these tests can be expressed as mass % carbon.  
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.  
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: 31-May-2022
• ICS: 71.060.10 - Chemical elements
• Technical Committee: D24 - Carbon Black
• Drafting Committee: D24.66 - Environment, Health, and Safety

Relations

• Refers: ASTM D1900-06(2015) - Standard Practice for Carbon Black—Sampling Bulk Shipments
• Effective Date: 01-Nov-2015
• Refers: ASTM D1799-03a(2014) - Standard Practice for Carbon Black—Sampling Packaged Shipments
• Effective Date: 01-Jun-2014
• Refers: ASTM D1900-06(2011) - Standard Practice for Carbon Black<char: emdash>Sampling Bulk Shipments
• Effective Date: 01-May-2011
• Refers: ASTM D1799-03a(2008) - Standard Practice for Carbon Black<span class='unicode'>&#x2014;</span>Sampling Packaged Shipments
• Effective Date: 01-Sep-2008
• Refers: ASTM D1900-06 - Standard Practice for Carbon Black-Sampling Bulk Shipments
• Effective Date: 01-Oct-2006
• Refers: ASTM D1799-03a - Standard Practice for Carbon Black&#8212;Sampling Packaged Shipments
• Effective Date: 01-Nov-2003
• Refers: ASTM D1799-03 - Standard Practice for Carbon Black&#8212;Sampling Packaged Shipments
• Effective Date: 10-Jun-2003
• Refers: ASTM D1799-02 - Standard Practice for Carbon Black&#8212;Sampling Packaged Shipments
• Effective Date: 10-Nov-2002
• Refers: ASTM D1799-93(1997) - Standard Practice for Carbon Black-Sampling Packaged Shipments
• Effective Date: 10-Nov-1997
• Refers: ASTM D1900-94(2002) - Standard Practice for Carbon Black&#8212;Sampling Bulk Shipments
• Effective Date: 15-Aug-1994

Overview

ASTM D7633-13(2022) - Standard Test Method for Carbon Black-Carbon Content provides a framework for determining the total carbon content in carbon black samples using instrumental analysis. This standard is critical for the rubber and carbon black manufacturing industries as it delivers authoritative guidance for accurately measuring the carbon percentage, essential for reporting carbon dioxide emissions and estimating process yield. The method applies to tread, carcass, and specialty carbon blacks produced by partial combustion or thermal decomposition, generally containing 95-100% carbon.

Key Topics

• Scope and Applicability

  • Targets carbon black produced for industrial applications, such as tire tread and specialty uses.
  • Applies to samples with a high carbon concentration (95-100%).

• Methodology

  • Involves weighing a sample and combusting it at high temperature (1350°C) in an oxygen stream.
  • The resulting emissions are analyzed for carbon dioxide using infrared (IR) absorption detectors.
  • The mass percent carbon is then reported directly from the analytical apparatus, calibrated with certified reference materials.

• Precision and Reporting

  • Strong precision guidelines are in place with repeatability and reproducibility estimates.
  • Results are reported to the nearest 0.1% carbon.
  • Emphasizes method validation through interlaboratory studies and calibration with reference materials.

• Safety and Compliance

  • Requires users to adhere to relevant health, safety, and environmental guidelines.
  • Ensures international recognition by aligning with World Trade Organization (WTO) standardization principles.

Applications

The ASTM D7633-13(2022) standard is widely adopted by:

• Manufacturers of carbon black and rubber products: Ensuring product consistency and meeting regulatory requirements for carbon content and reporting.
• Environmental compliance professionals: Calculating carbon dioxide emissions accurately for regulatory submissions and sustainability reporting.
• Quality control laboratories: Establishing consistent, repeatable protocols for verifying the carbon content in production batches.
• Research & Development: Supporting development of new carbon black types and process improvements through reliable carbon content analysis.
• Process optimization: Using carbon yield data to improve manufacturing efficiency and reduce waste.

The method’s focus on high-precision measurement and calibration ensures that carbon black producers and users can reliably compare data across facilities and regions, which is especially important for multinational operations and global supply chains.

Related Standards

Several other ASTM standards and industry references complement ASTM D7633-13(2022):

• ASTM D1799 - Practice for Carbon Black-Sampling Packaged Shipments
• ASTM D1900 - Practice for Carbon Black-Sampling Bulk Shipments
• ASTM D4483 - Practice for Evaluating Precision for Test Method Standards in Rubber and Carbon Black Industries

These standards are frequently referenced for sampling procedures, ensuring the test method’s validity, and assessing the precision of results. Adherence to these standards reinforces quality and regulatory compliance across the carbon black value chain.

Practical Value

Using ASTM D7633-13(2022) ensures:

• Reliable, standardized determination of carbon content in carbon black products.
• Accurate carbon mass percentage data for environmental impact assessments.
• Compliance with industrial and regulatory benchmarks for process yield and emissions.
• Enhanced confidence in product quality and process optimization for manufacturers and end-users.

This standard is an essential reference for anyone involved in carbon black analysis, regulatory compliance, or quality assurance in the carbon black supply chain. It ensures global harmonization of analytical methods and supports transparency in reporting carbon black carbon content.

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: D7633 − 13 (Reapproved 2022)
Standard Test Method for
Carbon Black—Carbon Content
This standard is issued under the fixed designation D7633; 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 Standards in the Rubber and Carbon Black Manufacturing
Industries
1.1 This test method covers the instrumental determination
of carbon content in a carbon black sample. Values obtained
3. Summary of Test Method
represent the total carbon content.
3.1 In this test method, a sample is weighed in a combustion
1.2 The method is applicable to tread, carcass and specialty
boat and the carbon content is determined by placing the boat
type carbon blacks obtained from partial combustion or ther-
in a tube furnace operating at 1350°C in a stream of oxygen
mal decomposition processes, which typically contain 95 to
resulting in complete combustion. Carbon in the sample is
100 % carbon.
oxidized to carbon dioxide. Moisture and particulates are
1.3 The results of these tests can be expressed as mass %
removed from the gas stream by traps filled with anhydrous
carbon.
magnesium perchlorate. The gas stream is then passed through
1.4 The values stated in SI units are to be regarded as a cell in which carbon dioxide concentration is measured by an
standard. No other units of measurement are included in this infrared (IR) absorption detector at a precise wavelength in the
standard. IR spectrum.
1.5 This standard does not purport to address all of the
3.2 This test method is for use with commercially available
safety concerns, if any, associated with its use. It is the
carbon analyzers equipped to carry out the combustion and
responsibility of the user of this standard to establish appro-
measurement operations automatically.
priate safety, health, and environmental practices and deter-
3.3 The carbon analyzer must be calibrated using an appro-
mine the applicability of regulatory limitations prior to use.
priate calibration standard (see 6.4).
1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard-
4. Significance and Use
ization established in the Decision on Principles for the
4.1 The total carbon content of a carbon black is a require-
Development of International Standards, Guides and Recom-
ment for the calculation and reporting of carbon dioxide
mendations issued by the World Trade Organization Technical
emissions. It can also be used in calculations to estimate yield
Barriers to Trade (TBT) Committee.
of the process.
2. Referenced Documents
5. Apparatus
2.1 ASTM Standards:
5.1 Analytical Balance,orequivalent,capableofaweighing
D1799 Practice for Carbon Black—Sampling Packaged
sensitivity of 1 mg or better resolution.
Shipments
D1900 Practice for Carbon Black—Sampling Bulk Ship-
5.2 Gravity Convection Drying Oven, capable of maintain-
ments
ing 125 6 5°C.
D4483 Practice for Evaluating Precision for Test Method
5.3 Measurement Apparatus, equipped to automatically
combust the sample and measure carbon content.
5.4 Combustion tube and boat made of a suitable material
This test method is under the jurisdiction ofASTM Committee D24 on Carbon
such as mullite, porcelain or zircon.
Black and is the direct responsibility of Subcommittee D24.66 on Environment,
Health, and Safety.
CurrenteditionapprovedJune1,2022.PublishedJuly2022.Originallyapproved
6. Reagents
in 2010. Last previous edition approved in 2018 as D7633 – 13 (2018). DOI:
10.1520/D7633-13R22.
6.1 Purity of Reagents—Reagent grade chemicals shall be
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
used in all tests. Unless otherwise indicated, it is intended that
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
all reagents shall conform to the specifications of the Commit-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. tee onAnalytical Reagents of theAmerican Chemical Society,
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7633 − 13 (2022)
where such specifications are available. Other grades may be 10.4 Weigh approximately 0.1 g of the sample or use
used, provided it is first ascertained that the reagent is of recommended mass per manufacturer.
sufficiently high purity to permit its use without lessening the
10.5 Spread the sample in the combustion boat and record
accuracy of the determination.
the sample weight.
6.2 Magnesium Perchlorate.
10.6 Initiate the analysis and place the sample in the
6.3 Oxygen, high purity, 99.9 %. instrument using a boat puller or the auto-sampler mechanism.
6.4 Calibration standard. 10.7 When the analysis is complete, the instrument should
indicate the carbon value. Refer to the manufacturer’s recom-
7. Sampling
mended procedure.
7.1 Samples of candidate carbon blacks shall be taken in
11. Report
accordance with Practice D1799 or D1900.
11.1 The percent carbon value is obtained directly from the
8. Preparation of Apparatus
apparatus.
8.1 Assemble the apparatus according to the manufacturer’s
11.2 Report results from individual determinations to the
instructions.
nearest 0.1 %.
8.2 Stabilize the furnace temperature at 1350 6 15°C.
NOTE 1—The most representative measurement of carbon content in a
carbon black sample is an average value from multiple individual
8.3 Makeaminimumoftwodeterminationstoconditionthe
determinations.Agood practice is to report a minimum of two individual
equipment or follow manufacturer’s recommendation to con-
determinations for a given sample.
dition equipment prior to calibrating the instrument.
12. Precision and Bias
9. Calibration
12.1 These precision statements have been prepared in
9.1 Calibrate the instrument per manufacturer’s recommen-
accordance with Practice D4483. Refer to this practice for
dation using a carbon calibration standard.
terminology and other statistical details.
9.2 Adjustment of Response of Measurement System—
12.2 The precision results in this precision and bias section
Weigh approximately 0.1 g of calibration standard or use
give an estimate of the precision of this test method with the
recommended mass per manufacturer.Analyze the sample (see
materials used in the particular interlaboratory program de-
Section 10). Repeat this procedure. Adjust instrument as
scribed below.The precision parameters should not be used for
recommended by the manufacturer until the absence of drift is
acceptance or rejection testing of any group of materials
indicated.
without documentation that they are applicable to those par-
9.3 Calibration Procedure—Follow the calibration proce-
ticular materials and the specific testing protocols of
...