Overview
ISO 13100:2024 - Methods for zeta potential determination - Streaming potential and streaming current methods for porous materials specifies standardized procedures to determine the zeta potential of porous materials that are saturated with a liquid and whose pores are readily accessible. The standard covers both direct current (DC) streaming potential and alternating current (AC) streaming current methods using aqueous media, applies to pores on the scale of hundreds of micrometres or smaller (no restriction on pore geometry), and is restricted to linear electrokinetic effects. There is no restriction on the numerical value of zeta potential or material porosity.
Key topics and requirements
- Measurement methods: Procedures for DC streaming potential (measurement of streaming potential coupling coefficient and calculation of zeta potential) and AC streaming current for particle deposits and consolidated porous bodies.
- Instrument setup and sample holders: Guidance on instrument location, sample holder design, and special sample-handling systems for different porous material types.
- Sample preparation and test solutions: Requirements for preparing saturated porous samples and choosing appropriate aqueous test solutions.
- Calibration, verification and quality: Procedures for calibration, reference materials, verification, and checks for repeatability, reproducibility, and intermediate precision.
- Sources of measurement error: Identification and mitigation of common errors such as contamination from previous samples, inappropriate preparation or solution, air bubbles, faulty electrodes, and limitations of theoretical approximations (e.g., Smoluchowski approximation).
- Reporting: Mandatory general and specific information to include when reporting zeta potential results for porous materials.
- Informative annexes: Electric double layer models in porous media, Debye length considerations, and porosity determination methods.
Practical applications
ISO 13100:2024 supports reliable electrokinetic characterization in applications such as:
- Surface-property assessment of porous ceramics, membranes, filters and catalyst supports
- Optimization of dispersant or surfactant dosing by identifying adsorption saturation plateaus
- Determination of isoelectric point (via titration with pH or reagents) for process control and formulation
- Comparative screening of materials by electrical surface behavior for R&D and quality control
- Research in colloid science, environmental engineering, and geophysics where electrokinetic signals are relevant
Who should use this standard
- Materials scientists and surface-chemistry researchers
- Analytical and testing laboratories performing zeta potential on porous solids
- Instrument manufacturers and calibration labs
- Process engineers working with membranes, porous catalysts, filters, and coated substrates
Related standards
- ISO 13099-1:2012 (terminology and related electrokinetic definitions referenced in ISO 13100:2024)
- Prepared by ISO/TC 24 (Particle characterization including sieving), Subcommittee SC 4
Keywords: ISO 13100:2024, zeta potential determination, streaming potential, streaming current, porous materials, electrokinetic methods, AC/DC methods, isoelectric point.