ASTM D4548-11(2019)

Standard Test Method for Anion-Cation Balance of Mixed Bed Ion-Exchange Resins

SIGNIFICANCE AND USE
5.1 This test method is applicable to the analysis of new materials that are sold as mixtures and to samples taken from regenerable units containing mixtures of anion-exchanging and cation-exchanging materials. It is used to determine the ratio of the components without separating them from each other.  
5.2 This test method is intended for mixtures of ion-exchange materials that have salt-splitting capacity as measured by Test Method E of Test Methods and Practices D2187 for cation-exchange resins, and Test Method H for anion-exchange resins. In the case of cation-exchange resins, these are styrene-based polymers with sulfonic acid functional groups. The anion-exchanging materials in this class are styrene-based materials with quaternary ammonium functional groups. The test method will determine the amount of anion-exchange material of any functionality present in the mixture. However, when anionic groups that are not salt-splitting are present, the values for cationic groups will be high due to the acidic character of the anion effluent. Cationic groups that do not split salts are not measured.  
5.3 Samples are analyzed in this test method as received. It is not necessary that the cation-exchanging resin be in the hydrogen form and the anion-exchanging resin be in the hydroxide form for this test method.  
5.4 This test method may be used to determine if new materials are balanced to meet their specification values. In operating regenerable units, it may be used to determine if the components are separating properly or remixing properly. It may also be used to check for improper balance in bedding or for loss of a component during operation.  
5.5 This test method begins with the conversion to the hydrogen and chloride forms. However, it may be combined with the determination of the residual chloride and sulfate sites by elution with sodium nitrate as described in Test Methods J and L in Test Methods and Practices D2187. In such cases the hydrogen ion as well...
SCOPE
1.1 This test method determines the ratio between the equivalents of anion-exchange capacity and the equivalents of cation-exchange capacity present in a physical mixture of salt-splitting anion-exchange material and salt-splitting cation-exchange material.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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-Oct-2019
• ICS: 71.100.40 - Surface active agents
• Technical Committee: D19 - Water
• Drafting Committee: D19.08 - Membranes and Ion Exchange Materials

Relations

• Replaces: ASTM D4548-11 - Standard Test Method for Anion-Cation Balance of Mixed Bed Ion-Exchange Resins
• Effective Date: 01-Nov-2019
• Refers: ASTM D1129-13(2020)e2 - Standard Terminology Relating to Water
• Effective Date: 01-May-2020
• Refers: ASTM D2187-17 - Standard Test Methods and Practices for Evaluating Physical and Chemical Properties of Particulate Ion-Exchange Resins
• Effective Date: 01-Aug-2017
• Refers: ASTM D1129-10 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2010
• Refers: ASTM D2187-94(2009) - Standard Test Methods for Physical and Chemical Properties of Particulate Ion-Exchange Resins
• Effective Date: 01-May-2009
• Refers: ASTM D1129-06ae1 - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D1129-06a - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM D1129-06 - Standard Terminology Relating to Water
• Effective Date: 15-Feb-2006
• Refers: ASTM D2187-94(2004) - Standard Test Methods for Physical and Chemical Properties of Particulate Ion-Exchange Resins
• Effective Date: 01-Jun-2004
• Refers: ASTM D1129-04e1 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2004
• Refers: ASTM D1129-04 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2004
• Refers: ASTM D1129-03a - Standard Terminology Relating to Water
• Effective Date: 10-Aug-2003
• Refers: ASTM D1129-03 - Standard Terminology Relating to Water
• Effective Date: 10-Mar-2003
• Refers: ASTM D1129-02a - Standard Terminology Relating to Water
• Effective Date: 10-Jul-2002

Overview

ASTM D4548-11(2019): Standard Test Method for Anion-Cation Balance of Mixed Bed Ion-Exchange Resins provides a reliable approach for determining the ratio of anion- to cation-exchange capacity in mixed bed ion-exchange resins. Published by ASTM International, this standard is essential for evaluating both new and in-service mixed bed ion-exchange materials commonly used in water treatment and related processes. The method ensures accuracy without the need for prior separation of the resin components, simplifying analysis and supporting quality control.

Key Topics

• Anion-Cation Balance: Measures the ratio between equivalents of anion-exchange and cation-exchange capacities in a physical mixture of salt-splitting ion-exchange resins.
• Applicable Materials: Focuses on mixtures of styrene-based polymers with sulfonic acid functional groups (cation-exchangers) and styrene-based polymers with quaternary ammonium groups (anion-exchangers).
• Sample Requirements: Analyzes samples as received, without requiring resins in specific ionic forms (e.g., hydrogen or hydroxide).
• Test Method:
  • Simultaneous conversion of the cation-exchange component to the hydrogen form and the anion-exchange component to the chloride form.
  • Elution of released ions (hydrogen and chloride) with sodium nitrate, followed by titration to determine capacities.
• Limitations:
  • Only salt-splitting groups are measured; other functional groups may affect results.
  • The method is not directly suitable for systems with substantial non-salt-splitting anionic groups.

Applications

Quality Control in Resin Manufacturing

• Verification of Product Specifications: Ensures that mixed bed ion-exchange resins meet specified anion-cation balance requirements.
• Assessment of New Materials: Useful for manufacturers to verify batch consistency before shipment.

Operation and Maintenance of Water Treatment Units

• Performance Monitoring: Determines whether components in regenerable mixed bed units are remixing or separating properly during operation.
• Troubleshooting: Diagnoses improper resin bed balance, component loss, or malfunction in mixed bed service.

Research and Development

• Material Characterization: Supports R&D by providing accurate measurement of anion-cation ratios in experimental resin blends.

Regulatory and Compliance

• International Standards Alignment: Developed in accordance with WTO Technical Barriers to Trade (TBT) guidelines, aiding organizations in meeting international quality assurance criteria.

Related Standards

• ASTM D1129: Terminology Relating to Water - provides definitions for relevant water treatment and testing terms.
• ASTM D1193: Specification for Reagent Water - outlines quality requirements for reagent water used in testing.
• ASTM D2187: Test Methods and Practices for Evaluating Physical and Chemical Properties of Particulate Ion-Exchange Resins - referenced for determining salt-splitting capacities.
• ASTM D4548: This document - the primary reference for anion-cation balance in mixed beds.

Practical Value

Implementing ASTM D4548-11(2019) in manufacturing and operational settings helps ensure the reliability and effectiveness of ion-exchange resins in critical water treatment processes. By delivering a standardized, easy-to-apply methodology, it enables routine quality assurance, supports troubleshooting in water processing plants, and lays the groundwork for compliance with both national and international regulatory mandates. Proper use of this standard improves operational efficiency and product consistency in industries reliant on mixed bed ion-exchange technology.

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: D4548 − 11 (Reapproved 2019)
Standard Test Method for
Anion-Cation Balance of Mixed Bed Ion-Exchange Resins
This standard is issued under the fixed designation D4548; 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 3.2 Definitions of Terms Specific to This Standard:
3.2.1 anion-exchange material, n—an ion-exchange mate-
1.1 This test method determines the ratio between the
rial capable of the reversible exchange of negatively charged
equivalents of anion-exchange capacity and the equivalents of
ions.
cation-exchange capacity present in a physical mixture of
3.2.2 cation-exchange material, n—an ion-exchange mate-
salt-splitting anion-exchange material and salt-splitting cation-
rial capable of the reversible exchange of positively charged
exchange material.
ions.
1.2 The values stated in SI units are to be regarded as
3.2.3 ion-exchange material, n—an insoluble material that
standard. No other units of measurement are included in this
has the ability to exchange reversibly certain ions in its
standard.
structure or attached to its surface as functional groups with
1.3 This standard does not purport to address all of the
ions in a surrounding medium.
safety concerns, if any, associated with its use. It is the
3.2.4 ion-exchange resin, n—a synthetic organic ion-
responsibility of the user of this standard to establish appro-
exchange material.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
3.2.5 mixed bed, n—a physical mixture of anion-exchange
1.4 This international standard was developed in accor-
material and cation-exchange material.
dance with internationally recognized principles on standard-
3.2.6 salt-splitting, adj—the ability of anion-exchange or
ization established in the Decision on Principles for the
cation-exchange materials to exchange hydroxide or hydrogen
Development of International Standards, Guides and Recom-
ions respectively for the ions in neutral salts.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4. Summary of Test Method
4.1 This test method consists of simultaneous conversion of
2. Referenced Documents
2 the cation-exchange component to the hydrogen form and the
2.1 ASTM Standards:
anion-exchange component to the chloride form with hydro-
D1129 Terminology Relating to Water
chloric acid. After rinsing to remove the excess acid, the
D1193 Specification for Reagent Water
hydrogen ion from the cation resin and the chloride ion from
D2187 Test Methods and Practices for Evaluating Physical
the anion resin are simultaneously eluted with neutral sodium
and Chemical Properties of Particulate Ion-Exchange
nitrate, and the amount eluted is determined by titration of the
Resins
effluent for both ions.
3. Terminology
5. Significance and Use
3.1 Definitions:
5.1 This test method is applicable to the analysis of new
3.1.1 For definitions of terms used in this standard, refer to
materials that are sold as mixtures and to samples taken from
Terminology D1129.
regenerableunitscontainingmixturesofanion-exchangingand
cation-exchangingmaterials.Itisusedtodeterminetheratioof
the components without separating them from each other.
This test method is under the jurisdiction of ASTM Committee D19 on Water
and is the direct responsibility of Subcommittee D19.08 on Membranes and Ion
5.2 This test method is intended for mixtures of ion-
Exchange Materials.
exchange materials that have salt-splitting capacity as mea-
Current edition approved Nov. 1, 2019. Published January 2020. Originally
sured by Test Method E of Test Methods and Practices D2187
approved in 1986. Last previous edition approved in 2011 as D4548 – 11. DOI:
10.1520/D4548-11R19.
for cation-exchange resins, and Test Method H for anion-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
exchange resins. In the case of cation-exchange resins, these
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
are styrene-based polymers with sulfonic acid functional
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. groups. The anion-exchanging materials in this class are
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4548 − 11 (2019)
styrene-based materials with quaternary ammonium functional tee onAnalytical Reagents of theAmerican Chemical Society.
groups. The test method will determine the amount of anion- Other grades may be used, provided it is first ascertained that
exchange material of any functionality present in the mixture. the reagent is of sufficiently high purity to permit its use
However, when anionic groups that are not salt-splitting are without lessening the accuracy of the determination.
present, the values for cationic groups will be high due to the
7.2 Purity of Water—Unless otherwise indicated, reference
acidic character of the anion effluent. Cationic groups that do
to water shall be understood to mean reagent water, conform-
not split salts are not measured.
ing to Specification D1193, Type IV.
5.3 Samples are analyzed in this test method as received. It
7.3 Ammonium Hydroxide (1+9)—Pour 1 vol of ammo-
is not necessary that the cation-exchanging resin be in the
nium hydroxide (sp gr 0.90) into 9 vol of water and mix well.
hydrogen form and the anion-exchanging resin be in the
7.4 Hydrochloric Acid (1+9)—Carefully pour 100 mL of
hydroxide form for this test method.
hydrochloric acid (sp gr 1.19) into 500 mL of water, stirring
5.4 This test method may be used to determine if new
constantly. Cool to 25 6 5°C and dilute to 1 L.
materials are balanced to meet their specification values. In
7.5 Isopropyl Alcohol, neutral.
operating regenerable units, it may be used to determine if the
components are separating properly or remixing properly. It 7.6 Methyl Orange Indicator Solution (0.5 g/L)—Dissolve
may also be used to check for improper balance in bedding or
0.05 g of methyl orange in water and dilute to 100 mL with
for loss of a component during operation. water.
5.5 This test method begins with the conversion to the
7.7 NitricAcid(1+9)—Pour1volofnitricacid(spgr1.42)
hydrogen and chloride forms. However, it may be combined into 9 vol of water and mix thoroughly.
with the determination of the residual chloride and sulfate sites
7.8 Phenolphthalein Indicator Solution (5.0 g/L)—Dissolve
by elution with sodium nitrate as described in Test Methods J
0.5 g of phenolphthalein in 50 mL of 95 % ethanol (see Note
and L in Test Methods and Practices D2187. In such cases the
1). Transfer to a volumetric flask and dilute to 100 mL with
hydrogen ion as well as the chloride ion is determined in the
water.
second sodium nitrate elution described in Test Method I of
NOTE 1—Isopropyl alcohol or specially denatured ethyl alcohol con-
Test Methods and Practices D2187, and the calculations given
forming to Formula 3A or 30 of the US Bureau of Internal Revenue may
herein are made using the titration values so determined.
be substituted for 95 % alcohol.
7.9 Potassium Chromate Solution (50 g/L)—Dissolve 5.0 g
6. Apparatus
of potassium chromate in 50 mL of water. Dilute to 100 mL
6.1 Test Apparatus, as shown in Fig. 1, shall consist of a
with water.
filter tube of at least 30 mLin capacity having a diameter of at
7.10 Silver Nitrate Solution, Standard (0.10 N)—Dry crys-
least 20 mm, containing a sintered glass plate of coarse (A)
talline silver nitrate at 105°C for 1 h and cool in a desiccator.
porosity, a 1-L separatory funnel, and a 1-L volumetric flask.
Weigh out 17 6 0.05 g ofAgNO .Transfer to a 1-Lvolumetric
flask with water. Dissolve in 500 mL of water. Dilute to 1-L
7. Reagents and Materials
with water at
...