ISO 2597-2:2019

INTERNATIONAL ISO
STANDARD 2597-2
Third edition
2019-04
Iron ores — Determination of total
iron content —
Part 2:
Titrimetric methods after
titanium(III) chloride reduction
Minerais de fer — Dosage du fer total —
Partie 2: Méthodes titrimétriques après réduction au chlorure de
titane(III)
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 . 2
4.1 Decomposition of the test portion . 2
4.1.1 Acid decomposition . 2
4.1.2 Fusion-filtration . . 2
4.2 Titration of iron . 2
5 Reagents . 2
6 Apparatus . 4
7 Sampling and samples . 4
7.1 Laboratory sample . 4
7.2 Preparation of test samples . 5
7.2.1 General. 5
7.2.2 Ores having significant contents of combined water or oxidizable compounds . 5
7.2.3 Ores outside the scope of 7.2.2 . 5
8 Procedure. 5
8.1 Number of determinations . 5
8.2 Blank test and check test . 5
8.3 Determination of hygroscopic moisture content. 6
8.4 Test portion . 6
8.5 Determination . 6
8.5.1 Decomposition of the test portion . 6
8.5.2 Reduction . 7
9 Expression of results . 8
9.1 Calculation of total iron content . 8
9.2 General treatment of results . 9
9.2.1 Repeatability and permissible tolerance . 9
9.2.2 Determination of analytical result .10
9.2.3 Between-laboratories precision .10
9.2.4 Check for trueness .10
9.2.5 Calculation of final result .11
9.2.6 Oxide factors .12
10 Test report .12
Annex A (normative) Flowsheet of the procedure for the acceptance of analytical values for
test samples .13
Annex B (normative) Procedure of Japanese weighing method .14
Bibliography .15
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 102, Iron ore and direct reduced iron,
Subcommittee SC 2, Chemical analysis.
This third edition cancels and replaces the second edition (ISO 2597-2:2015), which has been technically
revised with the following changes:
— the Scope has been reworded to describe the second method using perchloric acid;
— a terms and definitions clause has been added as Clause 3 and the subsequent clauses have been
renumbered accordingly;
— in 4.2 (previously 3.2) a description of the second method using perchloric acid has been added;
— in the second paragraph of 4.1.1 (previously 3.1.1), “water more hydrochloric acid” has been replaced
with “water and hydrochloric acid”;
— in 5.19 (previously 4.19), “5,58” has been replaced with “7,978 1”;
— Clause 5, potassium disulfate (K S O ) has been added as a reagent (5.23);
2 2 7
— in the sixth paragraph of 8.5.1.1 (previously 7.5.1.1), “4.20” has been replaced with “5.23”;
— in the description for V in 9.1 (previously 8.1), “4.13” has been replaced with “5.20”;
— in 9.2.4 (previously 8.2.4), Formula (8) and the relevant descriptions have been modified to harmonize
this subclause across all International Standards for which ISO/TC 102/SC 2 is responsible.
A list of all parts in the ISO 2597 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 2597-2:2019(E)
Iron ores — Determination of total iron content —
Part 2:
Titrimetric methods after titanium(III) chloride reduction
WARNING — This document may involve hazardous materials, operations and equipment. This
document does not purport to address all of the safety problems associated with its use. It is the
responsibility of the user of this document to establish appropriate health and safety practices.
1 Scope
This document specifies two titrimetric methods, free from mercury pollution, for the determination
of total iron content in iron ores, using potassium dichromate as titrant after reduction of the iron(III)
by tin(II) chloride and titanium(III) chloride. The excess reductant is then oxidized by either dilute
potassium dichromate (Method 1) or perchloric acid (Method 2).
Both methods are applicable to a concentration range of 30 % mass fraction to 72 % mass fraction of
iron in natural iron ores, iron ore concentrates and agglomerates, including sinter products.
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 385, Laboratory glassware — Burettes
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 2596, Iron ores — Determination of hygroscopic moisture in analytical samples — Gravimetric, Karl
Fischer and mass-loss methods
ISO 3082, Iron ores — Sampling and sample preparation procedures
ISO 80000-1:2009, Quantities and units — Part 1: General
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Principle
4.1 Decomposition of the test portion
4.1.1 Acid decomposition
For samples containing not more than 0,05 % mass fraction of vanadium, the test portion is treated
with hydrochloric acid in the presence of tin chloride.
The residue is filtered, ignited and treated with hydrofluoric and sulfuric acids. The mixture is fused
with potassium disulfate and the cold melt is dissolved in water and hydrochloric acid and combined
with the main iron solution, which is treated with potassium permanganate and evaporated.
4.1.2 Fusion-fi
...