FprEN ISO 14720-2

SLOVENSKI STANDARD
oSIST prEN ISO 14720-2:2025
01-maj-2025
Preskušanje keramičnih materialov - Ugotavljanje žvepla v neoksidativnih
keramičnih surovinah in osnovnih materialih - 2. del: Atomska emisijska
spektrometrija z induktivno sklopljeno plazmo (ICP AES) ali ionska kromatografija
(IC) po izpostavitvi ognju v pretoku kisika (ISO/DIS 14720-2:2025)
Testing of ceramic materials - Determination of sulfur in non-oxidic ceramic raw materials
and ceramic materials - Part 2: Inductively coupled plasma optical emission spectrometry
(ICP-OES) or ion chromatography (IC) after burning in the oxygen flow (ISO/DIS 14720-
2:2025)
Prüfung keramischer Werkstoffe - Bestimmung des Schwefelgehaltes in nichtoxidischen
keramischen Roh- und Werkstoffen - Teil 2: Optische Emissionsspektrometrie mit
induktiv gekoppeltem Plasma (ICP-OES) oder Ionenchromatographie (IC) nach
Verbrennung im Sauerstoffstrom (ISO/DIS 14720-2:2025)
Essai des matières céramiques - Détermination de la teneur en soufre des matières
premières céramiques non oxydes et des matériaux céramiques non oxydes - Partie 2:
Spectrométrie d'émission optique avec plasma couplé inductif (ICP-OES) ou
chromatographie ionique (IC) après combustion dans le courant d'oxygène (ISO/DIS
14720-2:2025)
Ta slovenski standard je istoveten z: prEN ISO 14720-2
ICS:
81.060.10 Surovine Raw materials
oSIST prEN ISO 14720-2:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 14720-2:2025
oSIST prEN ISO 14720-2:2025
DRAFT
International
Standard
ISO/DIS 14720-2
ISO/TC 33
Testing of ceramic materials -
Secretariat: BSI
Determination of sulfur in non-
Voting begins on:
oxidic ceramic raw materials and
2025-02-24
ceramic materials —
Voting terminates on:
2025-05-19
Part 2:
inductively coupled plasma optical
emission spectrometry (ICP-OES)
or ion chromatography (IC) after
burning in the oxygen flow
Essai des matières céramiques — Détermination de la teneur
en soufre des matières premières céramiques non oxydes et des
matériaux céramiques non oxydes —
Partie 2: Spectrométrie d'émission optique avec plasma couplé
inductif (ICP-OES) ou chromatographie ionique (IC) après
combustion dans le courant d'oxygène
ICS: 81.060.10
THIS DOCUMENT IS A DRAFT CIRCULATED
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IS THEREFORE SUBJECT TO CHANGE
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NOTIFICATION OF ANY RELEVANT PATENT
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PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 14720-2:2025(en)
oSIST prEN ISO 14720-2:2025
DRAFT
ISO/DIS 14720-2:2025(en)
International
Standard
ISO/DIS 14720-2
ISO/TC 33
Testing of ceramic materials -
Secretariat: BSI
Determination of sulfur in non-
Voting begins on:
oxidic ceramic raw materials and
ceramic materials —
Voting terminates on:
Part 2:
inductively coupled plasma optical
emission spectrometry (ICP-OES)
or ion chromatography (IC) after
burning in the oxygen flow
Essai des matières céramiques — Détermination de la teneur
en soufre des matières premières céramiques non oxydes et des
matériaux céramiques non oxydes —
Partie 2: Spectrométrie d'émission optique avec plasma couplé
inductif (ICP-OES) ou chromatographie ionique (IC) après
combustion dans le courant d'oxygène
ICS: 81.060.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
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BE CONSIDERED IN THE LIGHT OF THEIR
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Published in Switzerland Reference number
ISO/DIS 14720-2:2025(en)
ii
oSIST prEN ISO 14720-2:2025
ISO/DIS 14720-2:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Interferences . 2
5.1 Inductively coupled plasma optical emission spectrometry (ICP-OES) .2
5.1.1 Spectral interferences .2
5.1.2 Physical interferences .2
5.2 Ion chromatography (IC) .2
6 Apparatus . 3
7 Reagents . 3
8 Sampling and sample preparation . 4
9 Preparation . 4
9.1 Combustion device .4
9.2 Oxygen (7.10) .4
9.3 Inductively coupled plasma optical emission spectrometer (6.7) .4
9.4 Ion chromatograph (6.8) . .4
10 Calibration . 4
10.1 Inductively coupled plasma optical emission spectrometer .4
10.2 Ion chromatograph .4
11 Performance . 5
11.1 Determination of the blank value .5
11.2 Determination of the sulfur content .5
12 Calculation and report of the results . 5
13 Precision . 6
13.1 Repeatability .6
13.2 Reproducibility .6
14 Test report . 6
Annex A (informative) Example of a combustion device . 7
Annex B (informative) Example for suitable operating parameters for the determination of
sulfur by ion chromatography . . 8
Annex C (informative) Example for suitable operating parameters for the determination of
sulfur by inductively coupled plasma optical emission spectroscopy . 9
Annex D (informative) Results of the round-robin test . 10
Annex E (informative) Information regarding the validation of the uncertainty of the mean
value .13
Annex F (informative) Commercial Certified Reference Materials (CRM) . 14
Bibliography .15

iii
oSIST prEN ISO 14720-2:2025
ISO/DIS 14720-2:2025(en)
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 through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 14720-2 was prepared by Technical Committee ISO/TC 33, Refractories.
ISO 14720 consists of the following parts, under the general title Testing of ceramic materials — Determination
of sulfur in non-oxidic ceramic raw materials and ceramic materials:
— Part 1: Infrared measurement methods
— Part 2: Inductively coupled plasma optical emission spectrometry (ICP-OES) or ion chromatography (IC)
after burning in the oxygen flow

iv
oSIST prEN ISO 14720-2:2025
DRAFT International Standard ISO/DIS 14720-2:2025(en)
Testing of ceramic materials - Determination of sulfur in non-
oxidic ceramic raw materials and ceramic materials —
Part 2:
inductively coupled plasma optical emission spectrometry
(ICP-OES) or ion chromatography (IC) after burning in the
oxygen flow
1 Scope
This part of ISO 14720 defines a method for the determination of sulfur in non-oxidic ceramic raw materials
and ceramic materials, which are completely oxidized at a higher temperature in an oxygen atmosphere, for
example carbon and graphite materials.
For materials which are not completely oxidizable under these conditions, it is possible to determine sulfur
that can be released under these conditions, for example the adherent sulfur.
This part of ISO 14720 is applicable for materials with mass fractions of sulfur ≤ 10 % and mass fractions of
ash < 20 %, The defined method is limited for materials with mass fractions of barium < 10 mg/kg, because
the sulfur bonded in barium sulfate is not detectable with this method.
For the lower detection limit of this method, a mass fraction of sulfur of 0,5 mg/kg in the case of inductively
coupled plasma optical emission spectrometry (ICP-OES) and 5 mg/kg in the case of ion chromatography
(IC) has to be considered as a recommended value.
2 Normative references
The following referenced documents are indispensable for the application 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 11885, Water quality — Determination of selected elements by inductively coupled plasma optical emission
spectrometry (ICP-OES)
ISO 10304-1, Water quality — Determination of dissolved anions by liquid chromatography of ions — Part 1:
Determination of bromide, chloride, fluoride, nitrate, nitrite, phosphate and sulfate
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
sulfur content
mass fraction of inorganic and organic bound sulfur
4 Principle
The dried sample is oxidized in a flow of oxygen at a temperature of 1 100 °C using a porcelain crucible.
The resulting sulfur oxides are absorbed in a solution of sodium hydroxide and hydrogen peroxide. The
remaining material (ash) is dissolved and combined with the absorption liquid in the case of calcium-sulfate-

oSIST prEN ISO 14720-2:2025
ISO/DIS 14720-2:2025(en)
containing sample material. The concentration of sulfur in the sample solution is determined by inductively
coupled plasma optical emission spectrometry (ICP-OES) according to ISO 11885 or by ion chromatography
(IC) as sulfate according to ISO 10304-1 .
5 Interferences
5.1 Inductively coupled plasma optical emission spectrometry (ICP-OES)
5.1.1 Spectral interferences
The compensation of spectral interferences is performed according to the manual of the manufacturer of the
spectrometer.
NOTE 1 Spectral interferences can be caused by:
a) Overlapping with the emission line of another element;
b) Overlapping with molecular bands;
c) Unspecific background (for example scattering, recombinations).
Overlapping of lines can be compensated for by arithmetical correction of the raw data if applicable.
Correction factors are determined by measuring at least one undisturbed additional emission line of the
interfering element and considering the relation of the intensity of this emission line to the emission line
which interferes with the analyte element.
In the case of overlapping with molecular bands, an alternative emission line has to be chosen.
NOTE 2 Unspecific background is usually compensated for by measuring the background signal in the surroundings
of the analyte emission line.
5.1.2 Physical interferences
To compensate physical interferences, suitable measures shall be taken.
NOTE Physical interferences occur as plasma interferences or as transport interferences. Both are caused
by a different behaviour of the calibration solution compared to the sample solution based on a different chemical
composition. Plasma interferences are caused by changes in plasma conditions, for example temperature distribution
and electron density, leading to a changed excitation of emission lines. Transport interferences are caused by
differences in physical characteristics of the calibration solution and sample solution, mainly density, viscosity and
surface tension.
Some of the transport interferences can be reduced by using appropriate (peristaltic) pumps. Plasma
interferences as well as transport interferences can be reduced significantly by using suitable reference
lines of a reference element with the same concentration in both the calibration and analyte solution
(internal standard). Other possibilities are to equalize the chemical composition of the calibration and
sample solution as much as possible (matrix matching) or to use a standard addition procedure or a standard
addition calibration procedure instead of the standard calibration procedure.
5.2 Ion chromatography (IC)
To avoid cross-interferences by additional anions, suitable measures shall be taken.
NOTE Anions like chloride, bromide, fluoride, nitrite, nitrate, formiate and acetate in the absorption liquid may
lead to cross-interferences. By using the chromatographic parameters given in Annex B, the sulfate signal usually can
be separated completely from the signals of the other anions.

oSIST prEN ISO 14720-2:2025
ISO/DIS 14720-2:2025(en)
6 Apparatus
6.1 Combustion device, adjustable to (1 100 ± 20) °C, suitable for oxidizing the sample in a
...