ISO 21822:2019

INTERNATIONAL ISO
STANDARD 21822
First edition
2019-11
Fine ceramics (advanced ceramics,
advanced technical ceramics) —
Measurement of iso-electric point of
ceramic powder
Céramiques techniques — Mesure du point iso-électrique de poudres
céramiques
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 3
5 Apparatus and calibration . 3
5.1 Zeta potential analyser and calibration . 3
5.2 pH meter . 3
5.3 Sample dispersion vessel . 3
5.4 Sonicator . 4
5.5 Balance . 4
5.6 Temperature-control device . 4
5.7 Magnetic stirrer . 4
6 Operational procedures . 4
6.1 Dispersion solution . 4
6.2 pH-adjusting acid or base and electrolyte solution . 4
6.3 Sample preparation and dispersion . 4
6.3.1 Preparation . 4
6.3.2 Dispersion . 4
6.3.3 Stabilization . 5
7 Measurement . 5
8 Determination of the iso-electric point . 5
9 Test report . 6
Bibliography . 7
Foreword
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iv © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 21822:2019(E)
Fine ceramics (advanced ceramics, advanced technical
ceramics) — Measurement of iso-electric point of
ceramic powder
1 Scope
This document specifies the test method to determine the iso-electric point of fine ceramic powders,
which is measured in the state of suspension.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4316, Surface active agents — Determination of pH of aqueous solutions — Potentiometric method
ISO 13099-1, Colloidal systems — Methods for zeta-potential determination — Part 1: Electroacoustic and
electrokinetic phenomena
ISO 13099-2, Colloidal systems — Methods for zeta-potential determination — Part 2: Optical methods
ISO 13099-3, Colloidal systems — Methods for zeta potential determination — Part 3: Acoustic methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13099-1, ISO 13099-2 and
ISO 13099-3 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
zeta potential
ζ-potential
difference between the electric potential at the slipping plane and that of the bulk
...