ASTM D4789-20e1

Standard Test Method for Solution Color of Bisphenol A (4,4<emph type="ital">′</emph >-Isopropylidenediphenol)

SIGNIFICANCE AND USE
4.1 Color is caused by impurities in the bisphenol A. The acceptable amount of color depends on the end-use of the bisphenol A.  
4.2 This test method can be used for internal quality control. This method provides the information required to set specifications.
SCOPE
1.1 This test method covers the procedure for determination of the Platinum-Cobalt Color of bisphenol A (4,4′-Isopropylidenediphenol) dissolved in methanol.  
1.2 This test method has been found applicable for the determination of solution color of bisphenol A to 20 Pt–Co color units.  
1.3 The following applies for the purposes of determining the conformance of the test results using this test 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-Sep-2020
• ICS: 71.080.90 - Phenols
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.02 - Oxygenated Aromatics

Relations

• Refers: ASTM D4297-15(2020) - Standard Practice for Sampling and Handling Bisphenol A<brk/>(4,4<emph type="ital" >&#x2032;</emph> -Isopropylidinediphenol)
• Effective Date: 01-Jan-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 D4297-15 - Standard Practice for Sampling and Handling Bisphenol A<brk/>(4,4<emph type="ital" >&#x2032;</emph> -Isopropylidinediphenol)
• Effective Date: 01-Jun-2015
• Refers: ASTM E691-13 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-May-2013
• Refers: ASTM E691-11 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Nov-2011
• Refers: ASTM D4297-10 - Standard Practice for Sampling and Handling Bisphenol A (4,4' -Isopropylidinediphenol)
• Effective Date: 01-Jun-2010
• Refers: ASTM D4297-05(2009) - Standard Practice for Sampling and Handling Bisphenol A (4,4' -Isopropylidinediphenol)
• Effective Date: 01-Jun-2009
• Refers: ASTM E691-08 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Oct-2008
• 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 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 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 E29-06 - Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
• Effective Date: 01-May-2006
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM E691-05 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Nov-2005

Overview

ASTM D4789-20e1 is the internationally recognized standard test method for determining the solution color of Bisphenol A (4,4′-Isopropylidenediphenol) in methanol, measured via the Platinum-Cobalt Color Scale. This test method provides a reliable approach for color assessment, primarily to monitor product purity and ensure quality in industrial chemical processes. The level of color observed is directly related to the presence of impurities, and the results are critical for setting product specifications and for quality control in manufacturing and processing environments.

Key Topics

• Measurement Scope: The standard details a procedure for determining the Platinum-Cobalt (Pt-Co) Color of Bisphenol A solutions up to 20 Pt–Co color units, using SI units exclusively.
• Analysis Method: Bisphenol A is dissolved in methanol, and the solution's color is compared against calibrated Platinum-Cobalt standards using matched Nessler tubes and white light.
• Quality Control: This method is ideal for internal quality control, enabling manufacturers to monitor purity and set product specifications.
• Impurity Impact: Color intensity is typically caused by impurities. The acceptable color threshold is application-specific, underscoring the method’s role in end-use product assurance.
• Data Conformance: Results must be rounded in line with ASTM Practice E29, ensuring conformance and uniform reporting across laboratories.
• Safety Practices: Users are responsible for safety and regulatory compliance, following all relevant health and environmental practices.

Applications

ASTM D4789-20e1 is widely used in the chemical and plastics industries where Bisphenol A serves as a key raw material, particularly for:

• Manufacturing Quality Assurance: Ensures batch-to-batch consistency by detecting color changes attributable to contaminants, supporting compliance with global product quality standards.
• Product Specification Setting: Provides quantifiable color measurements to define and verify product acceptance criteria tailored to specific industry requirements.
• Supplier and Customer Assurance: Facilitates conformance data exchange between producers and customers, building confidence in product uniformity and minimizing disputes.
• Interlaboratory Comparability: Supports the implementation of quality protocols that guarantee color measurement reliability, equally recognized in both internal and external laboratory environments.
• Process Optimization: Helps identify deviations in production processes that might affect Bisphenol A purity, enabling timely corrective interventions.

Related Standards

For holistic quality control and data management in solution color analysis of Bisphenol A and related materials, the following ASTM standards provide critical guidelines and complementary methods:

• ASTM D1193: Specification for Reagent Water - Ensures reagent consistency and purity for accurate testing.
• ASTM D4297: Practice for Sampling and Handling Bisphenol A - Provides detailed sampling and handling procedures for test integrity.
• ASTM D6809: Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials - Offers frameworks for establishing quality systems.
• ASTM E29: Practice for Using Significant Digits in Test Data - Standardizes results rounding and presentation.
• ASTM E691: Practice for Conducting Interlaboratory Studies - Guides precision and reproducibility assessment through multi-lab studies.

Using these interrelated standards supports robust and reproducible solution color measurements, further enhancing product reliability throughout the Bisphenol A supply chain.

Keywords: Bisphenol A, solution color, Platinum-Cobalt Color, ASTM D4789, color test, quality control, 4,4′-Isopropylidenediphenol, chemical purity, industrial standards

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.
´1
Designation: D4789 − 20
Standard Test Method for
Solution Color of Bisphenol A (4,4'-Isopropylidenediphenol)
This standard is issued under the fixed designation D4789; 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.
ε NOTE—Research report information in Section 12 was updated editorially in February 2021.
1. Scope* -Isopropylidinediphenol)
D6809 Guide for Quality Control and Quality Assurance
1.1 This test method covers the procedure for determination
Procedures for Aromatic Hydrocarbons and Related Ma-
of the Platinum-Cobalt Color of bisphenol A (4,4'-
terials
Isopropylidenediphenol) dissolved in methanol.
E29 Practice for Using Significant Digits in Test Data to
1.2 This test method has been found applicable for the
Determine Conformance with Specifications
determination of solution color of bisphenol A to 20 Pt–Co
E691 Practice for Conducting an Interlaboratory Study to
color units.
Determine the Precision of a Test Method
1.3 The following applies for the purposes of determining 2.2 Other Documents:
OSHA Regulations, 29 CFR paragraphs 1910.1000 and
the conformance of the test results using this test method to
applicable specifications, results shall be rounded off in accor- 1910.1200
dance with the rounding-off method of Practice E29.
3. Summary of Test Method
1.4 The values stated in SI units are to be regarded as
3.1 Bisphenol A is dissolved in methanol. This solution is
standard. No other units of measurement are included in this
then transferred to a color comparison tube and the color
standard.
compared to that of the Platinum-Cobalt Color Standards,
1.5 This standard does not purport to address all of the
either visually or by means of a spectrophotometer. The color
safety concerns, if any, associated with its use. It is the
is reported as that closest to the applicable standard.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter- 4. Significance and Use
mine the applicability of regulatory limitations prior to use.
4.1 Color is caused by impurities in the bisphenol A. The
For specific hazard statements, see Section 8.
acceptable amount of color depends on the end-use of the
1.6 This international standard was developed in accor-
bisphenol A.
dance with internationally recognized principles on standard-
4.2 Thistestmethodcanbeusedforinternalqualitycontrol.
ization established in the Decision on Principles for the
This method provides the information required to set specifi-
Development of International Standards, Guides and Recom-
cations.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
5. Interferences
5.1 The presence of any turbidity or haze will affect the
2. Referenced Documents
color reading.
2.1 ASTM Standards:
5.2 AbisphenolAcolorthatisoff-hue,ortintedwithrespect
D1193 Specification for Reagent Water
to the color standards, may interfere with proper color com-
D4297 PracticeforSamplingandHandlingBisphenolA(4,4'
parison.
6. Apparatus
This test method is under the jurisdiction of ASTM Committee D16 on
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-
6.1 Color Comparison Tubes—Matched Nessler tubes with
bility of Subcommittee D16.02 on Oxygenated Aromatics.
50 mL or 100 mL graduation marks, or both, provided with
Current edition approved Oct. 1, 2020. Published December 2020. Originally
approved in 1988. Last previous edition approved in 2012 as D4789 – 12. DOI:
ground-on, optically clear, glass caps.
10.1520/D4789-20E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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
D4789 − 20
TABLE 2 Platinum-Cobalt Color Standards
6.2 Tube Racks, constructed to keep the tubes upright and to
permit visual comparison of light transmitted through Nessler Color Standard Stock Solution, Color Standard Stock Solution,
Number mL Number mL
tubes in the direction of their longitudinal axis; and so that
1 0.2 11 2.2
white light is passed through or reflected off a white glass plate
2 0.4 12 2.4
and directed with equal intensity through the tubes.
3 0.6 13 2.6
4 0.8 14 2.8
6.3 Filter Paper, glass fiber filter, 1.2-µm pore retention.
5 1.0 15 3.0
6 1.2 16 3.2
7. Reagents
7 1.4 17 3.4
8 1.6 18 3.6
7.1 Purity of Reagents—Reagent grade chemicals shall be
9 1.8 19 3.8
used in all tests. Unless otherwise indicated, it is intended that 10 2.0 20 4
all reagents shall conform to the specifications of the Commit-
tee onAnalytical Reagents of theAmerican Chemical Society,
where such specifications are available. Other grades may be
used, provided it is first ascertained that the reagent is of
8. Hazards
sufficiently high purity to permit its use without lessening the
8.1 Consult current OSHA regulations, suppliers’ Safety
accuracy of the determination.
Data Sheets, and local regulations for all materials utilized in
7.2 Methanol—Check for color against deionized water; if
this test method.
the methanol is not water white, redistill in an all-glass system.
9. Sampling
7.3 Platinum-Cobalt Stock Solution—Dissolve 1.245 g of
potassium chloroplatinate (K PtCl ) and 1.00 g of cobalt
2 6 9.1 Sample the material in accordance with Practice D4297.
chloride (CoCl ·6H O) in water. Carefully add 100 mL of
2 2
hydrochloric acid (HCl, sp gr 1.19) and dilute to 1 L with
10. Procedure
water. The absorbance of the 500 platinum-cobalt stock solu-
10.1 Weigh 50 g of bisphenol A. Transfer to a 150-mL
tion in a cell having a 10-mm light path, with reagent water in
Erlenmeyer flask.
a matched cell as the reference solution, must fall within the
10.2 Measure 70 mL of methanol. Add to the Erlenmeyer
limits given in Table 1.
flask containing the bisphenol A.
NOTE 1—This stock solution is commercially available from reputable
10.3 Stir until all the bisphenol A is dissolved.
chemical suppliers.
7.4 Platinum-Cobalt Standards—From the stock solution, 10.4 Transfer the methanol solution to a color comparison
prepare color standards in accordance with Table 2 by diluting tube, fill to the 50-mL or 100-mL mark, and cap the tube.
the required volumes to 100 mL with water in the Nessler
10.5 If there is any visible turbidity, pass the methanol
tubes. Cap the tubes and seal th
...