ISO 23028:2019

INTERNATIONAL ISO
STANDARD 23028
First edition
2019-07
Aluminium oxide primarily used
for the production of aluminium —
Preparation and storage of test
samples
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 . 1
5 Apparatus . 2
5.1 Rotary splitter . 2
5.2 Laboratory top-pan balance . 2
5.3 Sample bottles/containers . 2
5.4 Small rotary splitter . 2
5.5 Brush . 2
5.6 Powder funnel . 2
6 Procedure. 2
6.1 Sample integrity . 2
6.2 Mixing sample . 3
6.3 Division of sample . 3
6.4 Splitting of sample for analysis . 3
6.5 Identification of sample. 3
6.6 Storage and use . . 3
Annex A (informative) Rotary splitter . 5
Annex B (informative) Example of calculation for sample division . 7
Foreword
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This document was prepared by Technical Committee ISO/TC 226, Materials for the production of
primary aluminium.
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iv © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 23028:2019(E)
Aluminium oxide primarily used for the production of
aluminium — Preparation and storage of test samples
1 Scope
This document describes methods for the sample preparation of smelter-grade aluminium oxide. It
covers the reduction of a bulk sample between 1 kg and 20 kg to produce a sample that is suitable for
chemical and physical analysis. The reduced sample produced will be representative of the initial bulk
sample. The bulk sample is considered to be from one source.
The methods are suitable for dry, free-flowing aluminium oxide.
As the moisture content will influence many physical analyses, the method aims to minimize the
exposure of the sample to the atmosphere to avoid water absorption.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
increment
quantity of material collected in a single operation of a sample device
3.2
sample preparation
process of preparing the sample for analysis or testing, which may involve air-drying, particle size
reduction, mixing and division, and may be performed in several stages
3.3
sample preparation stage
stage in the sample preparation sequence of operations that may consist of sample drying, reduction in
particle size or mixing, and which culminates in sample
...