INTERNATIONAL ISO

STANDARD 23201

First edition
2015-11-15

Aluminium oxide primarily used

for production of aluminium —
Determination of trace elements
— Wavelength dispersive X-ray
fluorescence spectrometric method
Oxyde d’aluminium utilisé pour la production d’aluminium —
Détermination d’éléments traces — Spectrométrie de fluorescence des
rayons X par dispersion en longueur d’onde

Reference number
ISO 23201:2015(E)

© ISO 2015
ISO 23201:2015(E)


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 ISO 23201:2015(E)


Contents Page

Foreword......................................................................................................................................................................................................................................... iv
Introduction...................................................................................................................................................................................................................................v
1 Scope.................................................................................................................................................................................................................................. 1
2 Normative references....................................................................................................................................................................................... 1
3 Principle......................................................................................................................................................................................................................... 2
4 Reagents and materials.................................................................................................................................................................................. 2
5 Apparatus...................................................................................................................................................................................................................... 3
6 Sampling and samples..................................................................................................................................................................................... 5
7 Procedure..................................................................................................................................................................................................................... 5
7.1 General............................................................................................................................................................................................................ 5
7.2 Preparation of calibration specimens.................................................................................................................................. 6
7.2.1 Determination of loss of mass on fusion of flux and flux correction................................... 6
7.2.2 Preparation of intermediate calibration glass (ICG).......................................................................... 6
7.2.3 Preparation of the synthetic calibration disk (SCD).......................................................................... 7
7.2.4 Preparation of the blank calibration discs.................................................................................................. 9
7.3 Preparation of the sample discs................................................................................................................................................ 9
7.4 X-ray fluorescence measurement.......................................................................................................................................... 10
7.4.1 General instrumental conditions..................................................................................................................... 10
7.4.2 Guidelines for instrument optimization.................................................................................................... 11
7.4.3 Sample loading................................................................................................................................................................ 11
7.4.4 Monitor disc: correction for instrumental drift.................................................................................. 11
7.4.5 Measurements for calibration............................................................................................................................ 12
7.4.6 Measurement of test discs..................................................................................................................................... 13
8 Calculations.............................................................................................................................................................................................................13
8.1 Calculation of net intensity......................................................................................................................................................... 13
8.2 Comparison of duplicate measurements for the Al2O3 blanks and Synthetic
Calibration Discs (SCDs)............................................................................................................................................................... 14
8.2.1 SCDs criteria for the acceptability of duplicate measurements............................................ 14
8.2.2 Al2O3 blanks criteria for the acceptability of duplicate measurement........................... 14
8.3 Drift correction of measured intensities........................................................................................................................ 15
8.4 Calculation of the calibration parameters..................................................................................................................... 15
9 Consistency checks and reporting results...............................................................................................................................16
10 Precision..................................................................................................................................................................................................................... 16
11 Accuracy...................................................................................................................................................................................................................... 17
12 Quality assurance and control.............................................................................................................................................................17
13 Test report................................................................................................................................................................................................................. 17
Annex A (informative) Contamination issues and care of platinum ware...................................................................19
Annex B (normative) Example of instrument optimization.......................................................................................................21
Annex C (informative) Calculation of reagent masses for different sample/flux
combinations and synthetic calibration discs when omitting some elements..................................25
Annex D (informative) Preparation of monitor disc..........................................................................................................................27
Annex E (informative) Interlaboratory test program analysis of NIST 699 and ASCRM 27
smelter grade alumina, certified reference materials................................................................................................29
Annex F (informative) Comments on flux purity...................................................................................................................................31
Bibliography.............................................................................................................................................................................................................................. 32

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ISO 23201:2015(E)


Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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different types of ISO documents should be noted.  This document was drafted in accordance with the
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The committee responsible for this document is ISO/TC 226, Materials for the production of primary
aluminium.

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 ISO 23201:2015(E)


Introduction
This International Standard is based on Australian Standard AS 2879.7–1997, Alumina — Determination
of trace elements  — Wavelength dispersive X-ray fluorescence spectrometric method, developed by the
Standards Australia Committee on Alumina and Materials used in Aluminium Production to provide an
XRF method for the analysis of alumina.
The objective of this International Standard is to provide those responsible for the analysis of smelting-
grade alumina with a standardized, validated procedure that will ensure the integrity of the analysis.

© ISO 2015 – All rights reserved  v

INTERNATIONAL STANDARD ISO 23201:2015(E)

Aluminium oxide primarily used for production of

aluminium — Determination of trace elements —
Wavelength dispersive X-ray fluorescence spectrometric
method

1 Scope
This International Standard sets out a wavelength dispersive X-ray fluorescence spectrometric method
for the analysis of aluminium oxide for trace amounts of any or all of the following elements: sodium,
silicon, iron, calcium, titanium, phosphorus, vanadium, zinc, manganese, gallium, potassium, copper,
chromium and nickel. These elements are expressed as the oxides Na2O, SiO2, Fe2O3, CaO, TiO2, P2O5,
V2O5, ZnO, MnO, Ga2O3, K 2O, CuO, Cr2O3, and NiO on an un-dried sample basis.
The method is applicable to smelting-grade aluminium oxide. The concentration range covered for each
of the components is given in Table 1.

Table 1 — Applicable concentration range

Concentration range
Component
%
Na2O 0,10 to 1,00
SiO2 0,003 to 0,05
Fe2O3 0,003 to 0,05
CaO 0,003 to 0,10
TiO2 0,000 5 to 0,010
P2O5 0,000 5 to 0,050
V2O5 0,000 5 to 0,010
ZnO 0,000 5 to 0,010
MnO 0,000 5 to 0,010
Ga2O3 0,000 5 to 0,020
K2O 0,000 5 to 0,010
CuO 0,000 5 to 0,010
Cr2O3 0,000 5 to 0,010
NiO 0,000 5 to 0,010

2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
AS 2563, Wavelength dispersive X-ray fluorescence spectrometers — Determination of precision
AS 2706, Numeric values — Rounding and interpretation of limiting values
AS 4538.1-1999 (R2013), Guide to the sampling of alumina — Sampling procedures
AS 4538.2-2000 (R2013), Guide to the sampling of alumina — Preparation of samples

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