ISO 4907-1:2023

Overview

ISO 4907-1:2023 - Plastics - Ion exchange resin - Part 1 specifies standardized laboratory methods for determining the exchange capacity of acrylic anion exchange resins. The standard defines procedures to quantify three functional-group capacities: strong-base group capacity, weak-base group capacity and weak-acid group capacity of acrylic resins in their defined “standard form”. Methods rely on controlled chemical reactions and titrations and include requirements for reagents, apparatus, sampling, sample preparation, calculations and test reporting.

Key technical topics and requirements

• Scope and definitions: Clear definitions for “standard form acrylic anion exchange resin” and capacities expressed in mmol/g or mol/l.
• Principles: Determination of capacities by exchange reactions with neutral salts, acids or alkalis and subsequent titrations (chloride ion content, unreacted acid/alkali).
• Reagents and calibration: Analytical-grade reagents (e.g., NaOH, HCl, AgNO3, NaNO3) with described preparation and routine calibration procedures (examples: weekly calibration of standard solutions).
• Procedure elements:
  • Removal of external water and determination of resin water content (Annex B covers centrifugation method).
  • Specific test procedures for: strong-base, weak-base and weak-acid group capacities.
  • Calculation formulas and units for reporting capacities.
• Sampling and sample preparation: Normative guidance on representative sampling and transforming samples into the standard form required for testing (Annex A normative).
• Test report: Required information to document results for manufacturing control, inspection and arbitration.

Practical applications and users

ISO 4907-1:2023 is intended for organizations that manufacture, test, specify or use acrylic anion exchange resins, including:

• Resin manufacturers for product specification and batch quality control.
• Analytical and QC laboratories performing acceptance testing and certification.
• Process engineers in water treatment, petrochemicals, hydrometallurgy, food & pharmaceutical production who need reliable resin performance data.
• Procurement, regulatory bodies and arbitration panels requiring standardized test evidence.
• R&D groups developing or comparing ion exchange materials.

Practical benefits:

• Enables consistent measurement of exchange capacity across suppliers and labs.
• Supports product specification, process optimization and compliance testing.
• Facilitates technical communication and dispute resolution using a common method.

Related standards

• ISO 3696 - Water for analytical laboratory use (referenced for reagent water quality)
• ISO 4907 series - other parts of the series (see ISO catalogue for additional parts)

Keywords: ISO 4907-1:2023, acrylic anion exchange resins, exchange capacity, ion exchange resin testing, strong-base capacity, weak-base capacity, weak-acid capacity, titration methods, resin quality control.