FprEN 12485
(Main)Chemicals used for treatment of water intended for human consumption - Calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime - Test methods
Chemicals used for treatment of water intended for human consumption - Calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime - Test methods
This document specifies the methods used for the chemical analyses and the determination of physical properties of calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime used to treat water for human consumption.
This document specifies the reference methods and, in certain cases, an alternative method which can be considered to be equivalent.
Any other methods may be used provided they are calibrated, either against the reference methods or against internationally accepted reference materials, in order to demonstrate their equivalence.
Produkte zur Aufbereitung von Wasser für den menschlichen Gebrauch - Calciumcarbonat, Weißkalk, halbgebrannter Dolomit, Magnesiumoxid, Calciummagnesiumcarbonat und Dolomitkalk - Prüfverfahren
Dieses Dokument legt die Verfahren für die chemischen Analysen und zur Bestimmung von physikalischen Eigenschaften von Calciumcarbonat, Weißkalk, halbgebranntem Dolomit, Magnesiumoxid, Calciummagnesiumcarbonat und Dolomitkalk zur Aufbereitung von Wasser für den menschlichen Gebrauch fest.
Dieses Dokument legt die Referenzverfahren und in einigen Fällen ein Alternativverfahren, das als gleichwertig angesehen werden kann, fest.
Andere Verfahren dürfen unter der Voraussetzung angewendet werden, dass diese gegen die Referenzverfahren oder gegen international anerkannte Referenzmaterialien kalibriert sind, um ihre Gleichwertigkeit nachzuweisen.
Produits chimiques utilisés pour le traitement de l'eau destinée à la consommation humaine - Carbonate de calcium, chaux et dolomie semi calcinée - Méthodes d'analyse
Le présent document spécifie les méthodes utilisées pour réaliser les analyses chimiques et déterminer les propriétés physiques du carbonate de calcium, de la chaux, et de la dolomie semi-calcinée, de l’oxyde de magnésium, du carbonate de calcium et de magnésium et de la chaux dolomitique utilisés pour le traitement de l’eau destinée à la consommation humaine.
Le présent document spécifie les méthodes de référence et, dans certains cas, une méthode alternative qui peut être considérée comme étant équivalente.
D’autres méthodes peuvent être utilisées, dans la mesure où elles sont étalonnées, soit par rapport aux méthodes de référence, soit par rapport aux matériaux de référence internationalement reconnus, de manière à démontrer leur équivalence.
Kemikalije, ki se uporabljajo za pripravo pitne vode - Kalcijev karbonat, visoko kalcijevo apno in polžgan dolomit, magnezijev oksid in kalcij-magnezijev karbonat in dolomitno apno - Preskusne metode
General Information
Relations
Overview
The FprEN 12485:2024 standard, developed by CEN (European Committee for Standardization), specifies precise test methods for chemicals used in water treatment intended for human consumption. The chemicals covered include calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate, and dolomitic lime. This standard focuses on the chemical analysis and physical property determinations essential to ensure these substances meet quality and safety requirements for potable water treatment.
Replacing the previous EN 12485:2017, this updated document integrates new analytical techniques such as XRF methods and refines conditions like the loss on ignition temperature, aligning with enhanced regulatory and quality standards.
Key Topics
Scope and Application
This standard governs the reference and alternative analytical methods to evaluate the chemical composition and physical properties of water treatment chemicals, ensuring their proper use in treating drinking water.Sample Preparation and Analysis
Procedures for sampling, subsampling, and preparation are defined to maintain sample integrity. Emphasis is placed on rapid handling and airtight storage to prevent contamination by moisture and CO2.Chemical and Physical Test Methods
The standard details various gravimetric, titrimetric, and instrumental techniques for:- Determination of free water content and loss on ignition
- Measurement of carbon dioxide and residue insoluble in hydrochloric acid
- Quantification of water-soluble calcium oxide/hydroxide using reference and alternative sugar-soluble methods
- Analysis of calcium oxide (CaO), magnesium oxide (MgO), and other major and minor constituents through complexometric titration, AAS flame, or ICP-OES
- Detection of heavy metals including lead, cadmium, chromium, nickel, arsenic, antimony, selenium, and mercury using sensitive AAS or ICP techniques
- Particle size assessments for high-calcium lime through air-jet sieving or wet sieving
Performance and Reporting
Requirements are set for method repeatability, reproducibility, and detailed test reporting, ensuring reliable and consistent results. Calibration against internationally accepted reference materials is mandatory when alternative methods are adopted.
Applications
This standard applies principally to laboratories and organizations involved in:
Water treatment chemical manufacturing
Ensuring raw materials like lime and dolomite meet required compositions for effective water softening, pH adjustment, and contaminant removal.Water utilities and treatment plants
For quality control of chemicals used in purifying drinking water, maintaining compliance with health and safety regulations.Regulatory bodies and certification agencies
To evaluate and validate chemical products for potable water treatment with reference to recognized European norms and international standards.Research and development
Innovating and optimizing chemical agents for enhanced water treatment performance, relying on precise analytical data.
Using the prescribed test methods supports safe, effective water treatment, ultimately protecting public health by controlling chemical contaminants and ensuring water quality.
Related Standards
FprEN 12485 references and aligns with several related European and international standards to provide a comprehensive analytical framework:
- EN 1017:2014+A1:2017 – Half-burnt Dolomite
- EN 1018:2021 – Calcium Carbonate
- EN 12518:2014 – High-calcium Lime
- EN 16003:2011 – Calcium Magnesium Carbonate
- EN 16004:2011 – Magnesium Oxide
- EN 16409:2013 – Dolomitic Lime
- EN 459-2 – Building Lime Test Methods
- ISO 3696 – Water for Analytical Laboratory Use
- ISO 3165 – Sampling of Chemical Products for Industrial Use
By integrating these referenced standards, FprEN 12485 ensures harmonization of test methods, traceability of results, and adherence to best practices in chemical analysis for drinking water treatment.
This thorough and standardized approach promotes safe drinking water production, facilitating the effective use of critical chemicals in the water treatment industry. It supports regulatory compliance while enabling innovation in water treatment technologies.
Frequently Asked Questions
FprEN 12485 is a draft published by the European Committee for Standardization (CEN). Its full title is "Chemicals used for treatment of water intended for human consumption - Calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime - Test methods". This standard covers: This document specifies the methods used for the chemical analyses and the determination of physical properties of calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime used to treat water for human consumption. This document specifies the reference methods and, in certain cases, an alternative method which can be considered to be equivalent. Any other methods may be used provided they are calibrated, either against the reference methods or against internationally accepted reference materials, in order to demonstrate their equivalence.
This document specifies the methods used for the chemical analyses and the determination of physical properties of calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium carbonate and dolomitic lime used to treat water for human consumption. This document specifies the reference methods and, in certain cases, an alternative method which can be considered to be equivalent. Any other methods may be used provided they are calibrated, either against the reference methods or against internationally accepted reference materials, in order to demonstrate their equivalence.
FprEN 12485 is classified under the following ICS (International Classification for Standards) categories: 71.100.80 - Chemicals for purification of water. The ICS classification helps identify the subject area and facilitates finding related standards.
FprEN 12485 has the following relationships with other standards: It is inter standard links to EN 12485:2017. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase FprEN 12485 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of CEN standards.
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2024
Kemikalije, ki se uporabljajo za pripravo pitne vode - Kalcijev karbonat, visoko
kalcijevo apno in polžgan dolomit, magnezijev oksid in kalcij-magnezijev karbonat
in dolomitno apno - Preskusne metode
Chemicals used for treatment of water intended for human consumption - Calcium
carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium magnesium
carbonate and dolomitic lime - Test methods
Produkte zur Aufbereitung von Wasser für den menschlichen Gebrauch -
Calciumcarbonat, Weißkalk, halbgebrannter Dolomit, Magnesiumoxid,
Calciummagnesiumcarbonat und Dolomitkalk - Prüfverfahren
Produits chimiques utilisés pour le traitement de l'eau destinée à la consommation
humaine - Carbonate de calcium, chaux, dolomie semi-calcinée, oxyde de magnésium,
carbonate de calcium et de magnésium et chaux dolomitique - Méthodes d'essai
Ta slovenski standard je istoveten z: prEN 12485
ICS:
13.060.20 Pitna voda Drinking water
71.100.80 Kemikalije za čiščenje vode Chemicals for purification of
water
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
EUROPEAN STANDARD
prEN 12485
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2024
ICS 71.100.80 Will supersede EN 12485:2017
English Version
Chemicals used for treatment of water intended for human
consumption - Calcium carbonate, high-calcium lime, half-
burnt dolomite, magnesium oxide, calcium magnesium
carbonate and dolomitic lime - Test methods
Produits chimiques utilisés pour le traitement de l'eau Produkte zur Aufbereitung von Wasser für den
destinée à la consommation humaine - Carbonate de menschlichen Gebrauch - Calciumcarbonat, Weißkalk,
calcium, chaux, dolomie semi-calcinée, oxyde de halbgebrannter Dolomit, Magnesiumoxid,
magnésium, carbonate de calcium et de magnésium et Calciummagnesiumcarbonat und Dolomitkalk -
chaux dolomitique - Méthodes d'essai Prüfverfahren
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 164.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12485:2024 E
worldwide for CEN national Members.
prEN 12485:2023 (E)
Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 General requirements . 6
4.1 Number of determinations . 6
4.2 Methods for analysis . 6
4.3 Sample preparation . 7
4.4 Reagents . 8
4.5 Glassware . 8
4.6 Expression of results . 9
4.7 Repeatability and reproducibility limits . 9
4.8 Test report . 10
5 Determination of screen oversize of high-calcium lime . 10
5.1 Air-jet sieving method . 10
5.2 Wet sieving method. 12
6 Preparation of test solutions . 13
6.1 Fusion with lithium tetraborate . 13
6.2 Extraction with hydrochloric acid . 14
6.3 Microwave digestion with nitric acid . 15
6.4 Pressurized digestion with nitric acid . 16
7 Conventional methods of determining major and minor constituents . 16
7.1 Determination of free water . 16
7.2 Loss on ignition at 500 °C . 18
7.3 Determination of carbon dioxide . 18
7.4 Determination of residue insoluble in hydrochloric acid . 19
7.5 Determination of content of water soluble calcium oxide or calcium hydroxide
(reference method) . 20
7.6 Determination of sugar soluble calcium oxide or calcium hydroxide (alternative
method) . 22
7.7 Water-insoluble matter . 24
7.8 Determination of free CaO . 25
7.9 Determination of calcium oxide and magnesium oxide . 26
7.10 Determination of sulfate . 29
7.11 Determination of solubility index by conductivity . 30
7.12 Calculation of the composition of a commercial product . 33
8 Determination of constituents by modern techniques . 35
8.1 Determination of minor constituents by AAS flame technique . 35
8.2 Determination of major and minor constituents by ICP-OES . 39
9 Determination of chemical parameters. 45
9.1 Determination of lead, cadmium, chromium and nickel by AAS graphite tube
technique . 45
9.2 Determination of lead, cadmium, chromium and nickel by ICP-OES . 50
prEN 12485:2023 (E)
9.3 Determination of arsenic, antimony and selenium by AAS hydride technique . 54
9.4 Determination of mercury by cold-vapour technique . 57
Annex A (informative) Analytical scheme . 61
Annex B (informative) Precision data for the test methods . 68
Bibliography . 70
prEN 12485:2023 (E)
European foreword
This document (prEN 12485:2023) has been prepared by Technical Committee CEN/TC 164 “Water
supply”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12485:2010.
Annexes A and B are informative. For further information on methodology see [2] to [6].
Significant technical differences between this edition and EN 12485:2017 are as follows:
a) Table 1 – XRF methods are added;
b) changed for requirements of water quality;
c) loss on ignition 550 °C changed to 500 °C;
d) unglazed porcelain or platinum crucible changed in glazed porcelain or platinum crucible.
prEN 12485:2023 (E)
1 Scope
This document specifies the methods used for the chemical analyses and the determination of physical
properties of calcium carbonate, high-calcium lime, half-burnt dolomite, magnesium oxide, calcium
magnesium carbonate and dolomitic lime used to treat water for human consumption.
This document specifies the reference methods and, in certain cases, an alternative method which can
be considered to be equivalent.
Any other methods may be used provided they are calibrated, either against the reference methods or
against internationally accepted reference materials, in order to demonstrate their equivalence.
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.
EN 459-2, Building lime — Part 2: Test methods
EN 1017:2014+A1:2017, Chemicals used for treatment of water intended for human consumption — Half-
burnt dolomite
EN 1018:2021, Chemicals used for treatment of water intended for human consumption — Calcium
carbonate
EN 12518:2014, Chemicals used for treatment of water intended for human consumption — High-calcium
lime
EN 16003:2011, Chemicals used for treatment of water intended for human consumption — Calcium
magnesium carbonate
EN 16004:2011, Chemicals used for treatment of water intended for human consumption — Magnesium
oxide
EN 16409:2013, Chemicals used for treatment of water intended for human consumption — Dolomitic
lime
EN ISO 3696, Water for analytical laboratory use — Specification and test methods (ISO 3696)
ISO 3165, Sampling of chemical products for industrial use — Safety in sampling
ISO 4793:1980, Laboratory sintered (fritted) filters — Porosity grading, classification and designation
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at https://www.electropedia.org/
prEN 12485:2023 (E)
4 General requirements
4.1 Number of determinations
Two analyses shall be carried out to determine the various constituents (see Clause 6 to Clause 9; see
also 4.6).
4.2 Methods for analysis
The methods to be used for the analysis of half-burnt dolomite, calcium carbonate, high calcium lime,
magnesium oxide, calcium magnesium carbonate and dolomitic lime and the principle of each method
are listed in Table 1. Schematic diagrams of the analyses are given in Annex A (Figures A.1 to A.7).
The requirement values for free MgO and free Mg(OH) in half-burnt dolomite shall be expressed as
free MgO in accordance with EN 1017. The same requirement is related to free CaO. The requirement
value for MgO in magnesium oxide shall be expressed as MgO in dry substance in accordance with
EN 16004. Therefore, the analysis of half-burnt dolomite and magnesium oxide shall be performed on a
sample which is bound-water free. Before starting the chemical analysis, the loss on ignition at 550 °C
shall be determined as described in 7.2. The analysis itself shall be performed on the material obtained
after the determination of the loss on ignition.
The requirement values for calcium carbonate, hydrated lime and calcium magnesium carbonate shall
be expressed in dry substance in accordance with EN 1018, EN 12518 and EN 16003. Therefore, the
analysis of these products shall be performed on a sample which has been dried in accordance with the
procedure described in 7.1.
For the determination of the water-soluble content of high-calcium lime, the method in 7.5 is
considered as the reference method. The sugar method described in 7.6 can be used as an alternative
method if it is demonstrated that the results obtained with this method are equivalent to those of the
reference method.
The requirement values for CaO and MgO in dolomitic lime shall be expressed in accordance with
EN 16409. The requirement value for CaO and MgO in calcium magnesium dioxide shall be expressed as
CaO and MgO in bound-water free substance and for CaO and MgO in calcium magnesium dihydroxide
oxide shall be expressed as CaO and MgO in dry and bound-water free substance. Therefore, the
analysis of calcium magnesium dihydroxide oxide shall be performed on a sample which has been dried
in accordance with the procedure described in 7.1.
Table 1 — Methods for analysis
Determination Method Principle Standard
Screen oversize 5.1 Air-jet sieving EN 12518, EN 16409
5.2 Wet sieving EN 12518
Free water 7.1 Gravimetry EN 1018, EN 12518,
EN 16003, EN 16409
Loss on ignition at 500 °C 7.2 Gravimetry EN 1017, EN 12518,
EN 16004, EN 16409
Carbon dioxide 7.3 Gravimetry EN 1017, EN 12518,
EN 16004, EN 16409
Residue insoluble in hydrochloric 7.4 Acidimetry, Gravimetry EN 1018, EN 16003
acid
Water-soluble calcium oxide or 7.5 Acidimetric titration EN 12518
calcium hydroxide
prEN 12485:2023 (E)
Determination Method Principle Standard
Sugar-soluble calcium oxide or 7.6 Acidimetric titration EN 12518
calcium hydroxide
Water-insoluble constituents 7.7 Gravimetry EN 12518
Free calcium oxide 7.8 Extraction, acidimetric EN 1017, EN 16004
titration
Calcium oxide and magnesium 7.9 Complexometric titration EN 1017, EN 1018,
oxide EN 16003, EN 16004,
XRF melting tablet
EN 16409
XRF powder tablet
Sulfate 7.10 Gravimetry EN 1017
Solubility index 7.11 Conductivity EN 12518
Magnesium 8.1 AAS (flame) EN 1017, EN 1018,
EN 16003, EN 16409,
or ICP-OES
EN 16004
8.2 XRF melting tablet
XRF powder tablet
Silicium,Aluminium,Iron 8.1 AAS (flame) EN 1017, EN 12518,
EN 16003, EN 16004,
or ICP-OES
EN 16409
8.2 XRF melting tablet
XRF powder tablet
Manganese 8.2 ICP-OES EN 12518, EN 16409
XRF melting tablet
XRF powder tablet
Sulfur 8.2 ICP-OES EN 1017
XRF melting tablet
XRF powder tablet
EN 1017, EN 1018,
Lead, Cadmium, Chromium, Nickel 9.1 AAS (flameless)
EN 12518, EN 16003,
or or
EN 16004, EN 16409
9.2 ICP-OES
Arsenic, Antimony, Selenium 9.3 AAS (hydride) EN 1017, EN 1018,
EN 12518, EN 16003,
EN 16004, EN 16409
Mercury 9.4 AAS (cold-vapour technique) EN 1017, EN 1018,
EN 12518, EN 16003,
EN 16004, EN 16409
4.3 Sample preparation
The general recommendations specified in ISO 3165 shall be observed when sampling. Sampling shall
be performed in accordance with EN 459-2. For products less than 6 mm grain size, the size of the
sample shall be 1 l.
Before performing the chemical analyses, the size of the sample shall be reduced by using a sample
divider and/or by dividing it into four parts in order to obtain a suitable subsample. The coarse-grain
material in this sample shall be reduced to a size of less than 0,2 mm before performing the chemical
analysis.
prEN 12485:2023 (E)
When sampling milk of lime, the material from which the sample is to be taken shall be thoroughly
mixed with an electrically driven stirrer of adequate power. The milk of lime shall be dried before being
analysed chemically as described in 6.1.
Since the subsamples under examination are altered by the absorption of moisture and carbon dioxide,
their exposure to air shall be minimized. They shall therefore be transported and stored in air-tight
containers and all the handling shall be carried out as quickly as possible.
4.4 Reagents
All reagents shall be of a recognized analytical grade appropriate for the method being used.
EN ISO 3696 defines three types of water quality (essential requirements given below):
— Grade 3 suitable for most laboratory wet chemistry work (electrical conductivity < 0,5 mS/m
(at 25 °C));
— Grade 2 very low in contaminants and suitable for sensible analytical work (electrical
conductivity < 0,1 mS/m (at 25 °C));
— Grade 1 essentially free from contaminants and suitable for most stringent analytical requirements
(electrical conductivity < 0,01 mS/m (at 25 °C));
— In all cases the concentration of the element(s) to be determined shall be low enough not to
influence the results of the analysis. This can be verified by analysing the blank solution.
The concentrated liquids used for the reagents in this standard have the following densities (ρ)
(in grams per millilitre at 20 °C):
— hydrochloric acid 1,16 to 1,19;
— nitric acid 1,40 to 1,42;
— ammonium hydroxide solution 0,88 to 0,91;
— triethanolamine 1,12.
Dilutions are specified as the sum of the volumes. Thus, (1 + 2) dilute hydrochloric acid means 1 part by
volume of concentrated hydrochloric acid mixed with 2 parts by volume of water.
The concentrations of reference and standard volumetric solutions are specified as amount-of-
substance concentrations, c (mol/l), while those of stock and standard solutions are specified as
concentrations by mass, c (g/l or mg/l).
Suitable element solutions for atomic absorption spectroscopy (AAS) and for optical emission
spectroscopy by inductively coupled plasma (ICP-OES) are commercially available and can be used as
stock solutions. They shall be prepared for the purposes of analysis in accordance with the
manufacturer’s instructions. The appropriate element standard solutions are prepared in accordance
with the instructions given in this document.
This document makes no stipulations relating to the shelf life of stock, standard and reference solutions.
In the case of stock solutions having an element concentration of 1 g/l, the manufacturer generally
specifies a shelf life of one year. It is advisable to check the calibration solutions regularly.
4.5 Glassware
Glass containers and pipettes shall be cleaned with hot dilute nitric acid immediately before use and
then rinse with water. If determining trace elements rinse with grade 2 water.
prEN 12485:2023 (E)
4.6 Expression of results
The analytical results for the major and minor constituents shall be reported as mass fraction in %,
while those for trace elements shall be reported as mass fraction in milligrams per kilogram, as the
mean of two determinations. In general, analytical values shall be reported to three significant figures.
EXAMPLE:
— (CaO) = 91,2 %;
— (SiO ) = 3,70 %;
— (MnO ) = 0,15 %;
— (Cr) = 0,32 mg/kg;
— (Hg) = 0,05 mg/kg.
If the results of a duplicate determination differ from one another by more than twice the repeatability
standard deviation, the determination shall be repeated. The result shall then be deemed to be the
mean of the two results with the lowest difference.
To assess whether the analytical results meet the requirements laid down in EN 12518 for high-calcium
lime, in EN 1018 for calcium carbonate, in EN 1017 for half-burnt dolomite, in EN 16003 for calcium
magnesium carbonate, in EN 16004 for magnesium oxide and in EN 16409 for dolomitic lime, the
results have to be converted to the form in which the requirements are stated in the above standards.
Subclauses of this standard are given in Table 2 and contain the relevant calculation methods.
Table 2 — Methods for calculation of the results
Requirements from Parameter Required value for Calculation described in
standard
, CaO CaCO
CaO
free 3
CO MgCO
EN 1017 7.12.2.3
2 3
MgO MgO
free
CaO CaCO
EN 1018 7.12.2.1
MgO
MgCO
CO CaCO
EN 12518 7.12.2.4
2 3
MgO, loss on ignition (CO and H O)
2 2
EN 16004 at (1 050 ± 25) °C and
7.12.2.5
(500 ± 25) °C
MgO CaMg(CO )
3 2
EN 16003 7.12.2.2
MgCO
EN 16409 CaO, MgO CaO + MgO 7.12.2.6
4.7 Repeatability and reproducibility limits
The repeatability and reproducibility limits were determined in an interlaboratory test (see Annex B)
which was carried out in accordance with ISO 5725-2 and in which 28 laboratories took part.
prEN 12485:2023 (E)
4.8 Test report
The report shall contain the following information:
a) a reference to the method used;
b) a complete identification of the sample;
c) results obtained and the method of expression used (see 4.6)
d) sample pretreatment, e.g. method of digestion (see Clause 6);
e) any deviation from this standard and an indication of any circumstances which can have affected
the results.
5 Determination of screen oversize of high-calcium lime
5.1 Air-jet sieving method
5.1.1 General
The method is used to determine the retention on sieving using airjet sieving apparatus.
5.1.2 Apparatus
5.1.2.1 Air-jet sieving apparatus, of the general form shown in Figure 1. The apparatus shall be
set to give a pressure difference of 2 kPa to 2,5 kPa across the sieves.
Key
1 housing 7 test sample
2 dish 8 oversize material
3 sieve drum 9 undersize material
prEN 12485:2023 (E)
4 lid 10 air jet
5 slit-nozzle 11 air discharge
6 sieve 12 pressure gauge socket, with dust hood
Figure 1 — Air-jet sieving apparatus
5.1.2.2 Test sieves, 200 mm diameter, aperture sizes 0,60 mm and 0,09 mm.
The effective operation of some makes of air-jet apparatus can require non-standard sieve frames and
additional gaskets. This is permissible, provided the sieving medium and general method of
construction comply with the requirements of this document.
5.1.2.3 Trays or other suitable containers of sufficient size to contain the test portion.
5.1.2.4 Balance, accurate to 0,1 mg.
5.1.2.5 Soft brush.
5.1.2.6 Ultrasonic cleaning bath for cleaning the mesh of the sieves.
5.1.2.7 Mallet, if there is a tendancy for material to adhere to the lid of the apparatus. A rubber or
plastics tipped mallet is preferred.
5.1.3 Procedure
Weigh an appropriate amount (between 10 g and 50 g pending on the type of material) of the dry
sample to the nearest 1 mg (m). Fit the test sieve with the aperture size 0,09 mm into the apparatus and
transfer all of the test portion onto the sieve mesh. Take care not to lose any of the test portion.
Fit the lid and switch on the apparatus. Check that the vacuum created is above the minimum value
stated in the manufacturer’s instructions, and that the slit nozzle is rotating properly.
If material adheres to the lid of the apparatus, gently tap the centre of the lid with the mallet.
If the material agglomerates under the action of the air-jet, interrupt the sieving process, and break up
the agglomerates with the soft brush.
After (5 ± 0,2) min, switch off the apparatus and carefully remove the sieve. Transfer the material
retained on the sieve into a tray or other suitable container. Carefully clean the mesh of the sieve over
the tray using a soft brush.
Determine the mass of the residue, including the material brushed from the sieve mesh, and record the
mass to the nearest 1 mg.
Refit the sieve into the apparatus and transfer all of the residue back to the sieve mesh. Repeat the
weighing and sieving stages until the sieving end-point has been achieved, and record the end-point
mass to the nearest 1 mg. The sieving end-point is defined as being when not more than 0,2 % of the
mass of the original test portion passes through the sieve in 1 min.
Fit the 0,60 mm test sieve into the apparatus, and repeat the weighing and sieving stages until the mass
of the residue confirms that the sieving end-point has been reached. Record the end-point mass to the
nearest 1 mg.
5.1.4 Expression of results
The mass retained on each sieve expressed as m (P or ) in mass fraction in %, is given by the
0,60 0,09
following formula:
prEN 12485:2023 (E)
m×100
m P = (1)
( )
0,60 or 0,09
m
where
m is the mass of the sample, in grams;
m is the mass of the residue retained on the test sieves, in grams.
5.2 Wet sieving method
5.2.1 General
The method is exclusively used for the determination of the retentions on sieving of milk of lime as
specified in EN 12518.
5.2.2 Apparatus
5.2.2.1 Balance, accurate to 0,1 mg.
5.2.2.2 500 ml wide-mouthed bottle, or other suitable vessel which can be sealed with a
stopper.
5.2.2.3 200 mm diameter 0,60 mm and 0,09 mm aperture size test sieves.
5.2.2.4 5 mm bore rubber or plastics tubing.
5.2.2.5 Drying oven, thermostatically controlled to maintain a temperature of (105 ± 5) °C.
5.2.2.6 Two sintered glass filter crucibles, of porosity 2 (as specified in ISO 4793:1980)
(maximum porosity diameter 40 µm to 100 μm) with filter flask and adapter funnel for crucibles.
5.2.2.7 Desiccator.
5.2.2.8 Wash bottle.
5.2.2.9 Filtration apparatus.
5.2.3 Procedure
Superimpose the 0,60 mm mesh test sieve on the 0,09 mm mesh test sieve and wet the sieves with
water. Place a volume of milk of lime containing (50 ± 0,5) g of dry substance in a 500 ml wide-mouthed
bottle. Replace the stopper and shake the bottle for about 30 s. Remove the stopper immediately and
pour the contents of the bottle onto the sieves. Wash any residue remaining in the bottle or on the
stopper with a jet of water from the 5 mm bore tubing and at a pressure equal to a head of 1,2 m
(approximately 10 kPa) on to the sieves. Then use the jet to wash the residue on the 0,60 mm mesh test
sieve for (2 ± 0,1) min. Do not rub the residue through the sieve and take care not to flood the lower
sieve during the operation. At the end of this period, wash the residue to one side of the sieve.
Detach the 0,60 mm mesh test sieve and, using a wash bottle, transfer the residue from the sieve
through a glass funnel into one of the tared, sintered glass filter crucibles connected to the filtration
apparatus. When all the residue has been washed into the filter, and the water extracted, remove the
filter containing the residue and dry it at (105 ± 5) °C for 1 h. Cool the dried filter in a desiccator and
reweigh.
Wash the residue on the 0,09 mm mesh test sieve for (5 ± 0,2) min. Transfer the residue to a tared filter
crucible, dry at (105 ± 5) °C until constant mass is reached, cool and reweigh as described above.
prEN 12485:2023 (E)
5.2.4 Expression of results
The mass retained on each sieve expressed as m (P ) in mass fraction in % is given by the
0,60 or 0,09
following formula:
m×100
m P = (2)
( )
0,60 or 0,09
m
where
m is the mass of the dry substance in the test portion, in grams;
m is the mass of the residue retained on the test sieves, in grams.
6 Preparation of test solutions
6.1 Fusion with lithium tetraborate
6.1.1 General
Fusion with lithium tetraborate is used to dissolve:
— high-calcium lime as specified in EN 12518 in order to determine silicon, aluminium, iron and
manganese;
— half-burnt dolomite as specified in EN 1017 in order to determine calcium, magnesium, silicon,
aluminium and iron;
— calcium carbonate as specified in EN 1018 in order to determine calcium and magnesium;
— magnesium oxide as specified in EN 16004 in order to determine magnesium, silicon, aluminium
and iron;
— calcium magnesium carbonate as specified in EN 16003 in order to determine calcium and
magnesium;
— dolomitic lime as specified in EN 16409 in order to determine calcium, magnesium, silicon,
aluminium, iron and manganese.
6.1.2 Principle
After fusing the sparingly soluble oxide constituents of the sample with lithium tetraborate, the fusion
cake is dissolved in hydrochloric acid and the solution made up to 250 ml in a volumetric flask. Calcium,
magnesium, silicon, aluminium, iron and manganese are determined in aliquot parts of this solution by
flame-AAS (8.1) or ICP-OES (8.2).
6.1.3 Reagents
6.1.3.1 Lithium tetraborate, Li B O
2 4 7.
6.1.3.2 Hydrochloric acid, ρ = 1,16 g/ml.
6.1.3.3 Hydrochloric acid, diluted, (1 + 5).
prEN 12485:2023 (E)
6.1.4 Apparatus
Ordinary laboratory apparatus and the following:
6.1.4.1 Platinum-gold crucible.
6.1.4.2 Hot plate.
6.1.5 Procedure
Weigh (0,25 ± 0,02) g to the nearest 0,1 mg of the sample into a platinum-gold crucible and add 1,5 g of
lithium tetraborate (6.1.3.1). Roast at (1 000 ± 25) °C until the melt is clear. Remove from the heat,
cover the crucible with a watch glass and stand the crucible in water for a few seconds, remove and
allow it to stand until it has cooled completely.
Transfer the cold melt to a beaker using approximately 50 ml of hydrochloric acid (6.1.3.3) and dissolve
while stirring and heating at 100 °C. Then transfer the solution to a 250 ml volumetric flask with
water (4.4) and, after cooling to room temperature, add each 10 ml of the appropriate reagent solutions
(8.1.2.6 and 8.1.2.7 for the AAS measurement) or 1 ml of scandium solution (8.2.2.2, internal standard
solution for the ICP measurement) and make up to the mark with water (digestion solution (I) for AAS
and (II) for ICP).
6.2 Extraction with hydrochloric acid
6.2.1 General
Extraction with hydrochloric acid is used to dissolve samples exclusively in order to determine calcium
and magnesium.
6.2.2 Principle
The sample is boiled with hydrochloric acid and the solution filtered. The pH value is adjusted to 6 to 7
to precipitate the iron (III) and aluminium hydroxides. After refiltering, the filtrate is transferred to a
suitable volumetric flask.
6.2.3 Reagents
6.2.3.1 Hydrochloric acid, ρ = 1,16 g/ml.
6.2.3.2 Hydrogen peroxide solution, c (H O ) = 30 % (m/m).
2 2
6.2.3.3 Hydrogen peroxide solution, diluted, 1 + 9.
6.2.3.4 Ammonium hydroxide solution, c (NH ) = 25 % (m/m).
6.2.3.5 Ammonium hydroxide solution, diluted, 1 + 9.
6.2.3.6 Ammonium chloride, NH Cl.
6.2.4 Apparatus
Ordinary laboratory apparatus and the following:
6.2.4.1 Hot plate.
6.2.4.2 Magnetic stirrer and magnetic rod.
prEN 12485:2023 (E)
6.2.4.3 pH-meter with glass electrode.
6.2.5 Procedure
Weigh (1 ± 0,1) g of the sample to the nearest 1 mg, transfer it to a 250 ml beaker, moisten with 10 ml of
water, then gradually add 30 ml of hydrochloric acid (6.2.3.1). Make the solution up to about 100 ml
with water then boil it for 10 min. After boiling, filter the solution immediately through a fluted filter
paper (particle retention size 2,5 μm) into a 400 ml beaker and wash the residue well with water.
Add about 4 g of ammonium chloride (6.2.3.6) and a few drops of hydrogen peroxide (6.2.3.3) to the
solution, then dilute with about 150 ml of water and heat to boiling. During boiling, add ammonium
hydroxide solution dropwise (6.2.3.4) to adjust the pH value to 6 to 7 and precipitate aluminium
hydroxides and iron hydroxides and the silicic acid.
Continue boiling for 3 min and, after the precipitate has settled, filter the solution immediately through
a fluted filter paper (particle retention size 2,5 μm) into a 500 ml volumetric flask. Wash the filter
residue three times with ammonium hydroxide solution (6.2.3.5) and three times with water. After the
solution has cooled to room temperature, make the solution up to the mark with water and shake the
contents of the flask thoroughly (digestion solution III).
6.3 Microwave digestion with nitric acid
6.3.1 General
The purpose of this method of digestion is to release trace elements from the accompanying matrix and
determine the content of the various elements.
6.3.2 Principle
The sample is weighed into a perfluoroalkoxyethylene (PFA) beaker and nitric acid is added. After the
mixture has been placed in a microwave apparatus, digestion is carried out. Any undissolved
component is removed by filtering and the supernatant is used to determine the elements concerned.
6.3.3 Reagents
6.3.3.1 Nitric acid, ρ = 1,40 g/ml.
6.3.4 Apparatus
Ordinary laboratory apparatus and the following:
6.3.4.1 Microwave digestion apparatus, equipped with PFA digestion vessels and a
programmable pressure and temperature control unit. Performance ≥ 600 W.
6.3.4.2 50 ml polypropylene pressure vessel with screw lid.
6.3.4.3 Filtering apparatus.
6.3.5 Procedure
The mass of the test sample depends on the test method. For AAS, the recommended mass is
(0,5 ± 0,05) g and for ICP-OES (3 ± 0,05) g, weighed to the nearest 0,1 mg. In the first case, moisten the
sample with 4 ml of water and carefully add 3 ml of nitric acid (6.3.3.1), in the second case moisten with
5 ml of water and add 10 ml of nitric acid (6.3.3.1).
Seal the digestion vessel and place in the microwave apparatus. Before programming the apparatus, the
heating conditions shall be determined, and a temperature and pressure versus time plot shall be
prepared.
prEN 12485:2023 (E)
Subject the test sample to a pressure of 500 kPa to 700 kPa and to a temperature of 90 °C for 10 min
during a heating-up phase. Then subject the test sample to a pressure of 1 000 kPa and a temperature
between 120 °C and 150 °C for 15 min to 20 min. Allow the digestion vessel to cool to room
temperature. Open the digestion vessel, introduce the solution into a 100 ml volumetric flask rinse and
make up to the mark with water. Filter and transfer the solution (digestion solution IV) to a
polypropylene vessel in order to avoid adsorption on the glass.
6.4 Pressurized digestion with nitric acid
6.4.1 General
The purpose of this method of digestion is to release trace elements from the accompanying matrix and
determine the content of the various elements.
6.4.2 Principle
The sample is weighed out into a polytetrafluorethylen (PTFE) beaker and nitric acid is added. After the
mixture has been placed in a pressure shell, digestion is carried out at 130 °C. Any undissolved
component is removed by filtering and the supernatant is used to determine the elements concerned.
6.4.3 Reagent
6.4.3.1 Nitric acid, ρ (HNO ) = 1,40 g/ml.
6.4.4 Apparatus
Ordinary laboratory apparatus and the following:
6.4.4.1 Pressure digestion system, consisting of a PTFE digestion vessel, pressure shell and a
heater.
6.4.4.2 50 ml polypropylene pressure vessel with screw lid.
6.4.4.3 Filtering apparatus.
6.4.5 Procedure
Weigh (0,5 ± 0,05) g to the nearest of 0,1 mg of the sample into the digestion vessel, moisten the sample
with 2 ml of water and add carefully 5 ml of nitric acid (6.4.3.1). Seal the pressure vessel, place it in a
cold drying oven and heat to 130 °C. After about 15 min, remove the pressure vessel from the drying
oven and cool it to room temperature. Open the pressurized digestion system, introduce the solution
into a 100 ml volumetric flask, rinse and make up to the mark with water. Filter and transfer the
solution (digestion solution V) to a polypropylene vessel in order to avoid adsorption on the glass.
7 Conventional methods of determining major and minor constituents
7.1 Determination of free water
7.1.1 General
Free water means the moisture attached to the product, in the case of milk of lime, it refers to the water
content of the suspension. The method does not apply for high-calcium quicklime, half-burnt dolomite
or calcium magnesium dioxide. The determination of the water content of milk of lime is required to
calculate the water-soluble content of the suspended hydrated lime (see 7.5).
prEN 12485:2023 (E)
7.1.2 Principle
When heating a sample of hydrated high-calcium lime, calcium carbonate, calcium magnesium
carbonate or calcium magnesium dihydroxide oxide to (105 ± 5) °C, or for milk of lime to (150 ± 5) °C
the free water is driven off. The loss of mass at this temperature is referred to as free water.
7.1.3 Apparatus
Ordinary laboratory apparatus and the following:
7.1.3.1 Drying oven, thermostatically controlled to maintain a temperature of (105 ± 5) °C or
(150 ± 5) °C (alternative equipment 1).
7.1.3.2 Automated moisture balance, being capable to be controlled between (105 ± 5) °C or
(150 ± 5) °C (alternative equipment 2).
7.1.3.3 Analytical balance accurate to 0,1 mg.
7.1.3.4 Desiccator containing drying agent.
7.1.3.5 Glazed porcelain or platinum crucible.
7.1.3.6 Pipette.
7.1.4 Procedure
7.1.4.1 Hydrated high-calcium lime, calcium carbonate, calcium magnesium carbonate and
calcium magnesium dihydroxide oxide
Weigh (5 ± 0,1) g to a nearest 1 mg of the sample in the as-delivered state in a pre-weighed crucible. Dry
the sample until constant mass using the oven (7.1.3.1) or the balance (7.1.3.2). When using the oven
limit the time of drying to approximately 2 h. Cover the crucible after removing it from the oven to
prevent carbon dioxide and water vapour in the atmosphere from being absorbed. Cool in the
desiccator and reweigh.
7.1.4.2 Milk of lime
Homogenize the suspension by shaking before taking the sample aliquot. Use a pipette to take
approximately 20 g and weigh to the nearest of 0,1 mg in a glass vessel. Dry the sample to constant
mass using the oven (7.1.3.1) or the balance (7.1.3.2). Cover the crucible after removing it from the oven
to prevent carbon dioxide and water vapour in the atmosphere from being absorbed. After cooling
down to ambient temperature in the dessicator, determine the loss in mass.
7.1.5 Expression of results
The free water content expressed as (H2O) in mass fraction in % is given by the following formula:
()mm−
(3)
ω H O ×100
( )
m
where
m is the mass of the test portion before heating, in grams;
m is the mass of the test portion after heating, in grams.
=
prEN 12485:2023 (E)
7.2 Loss on ignition at 500 °C
7.2.1 General
The method is used to determine the loss on ignition after drying as specified in 7.1.
7.2.2 Principle
The loss on ignition at 500 °C is basically due the water of hydration.
7.2.3 Apparatus
Ordinary laboratory apparatus and the following:
7.2.3.1 Electric furnace capable of being maintained at (500 ± 25) °C, with a thermoelectric
temperature indicator.
7.2.3.2 Analytical balance accurate to 0,1 mg.
7.2.3.3 Desiccator containing phosphorous pentoxide, P O .
2 5
7.2.3.4 Glazed porcelain or platinum crucible.
7.2.4 Procedure
Weigh (5 ± 0,1) g to the nearest of 1 mg of the sample (m ) in a pre-weighed crucible. Heat the sample
in the furnace at (500 ± 25) °C for 2 h and then cool it in a desiccator. Cover the crucible after removing
it from the furnace to prevent carbon dioxide and water vapour in the atmosphere from being
absorbed. Cool in the desiccator and weigh (m ).
7.2.5 Expression of results
The loss on ignition at 550 °C expressed as LoI in mass fraction in % is given by the following formula:
mm−
( )
(4)
LoI ×100
( )
m
where
m is the mass of the sample before ignition at (500 ± 25) °C, in grams;
m is the mass of the sample after ignition at (500 ± 25) °C, in grams.
7.3 Determination of carbon dioxide
7.3.1 General
The method is used to determine carbon dioxide in high-calcium lime as specified in EN 12518, in half-
burnt dolomite as specified in EN 1017, in magnesium oxide as specified in EN 16004 and in dolomitic
lime as specified in EN 16409.
7.3.2 Principle
The carbon dioxide content of the materials concerned is determined from the loss on ignition at
1 050 °C. The loss on ignition at 500 °C is basically due to free water and the water of hydration. The
difference in mass between the loss on ignition at (1 050 ± 25) °C and the loss on ignition at
(500 ± 25) °C is equal to the carbon dioxide content of the product.
=
prEN 12485:2023 (E)
7.3.3 Apparatus
Ordinary laboratory apparatus and the following:
7.3.3.1 Electric furnace capable of being maintained at (1 050 ± 25) °C, with a thermoelectric
temperature indicator.
7.3.3.2 Analytical balance accurate to 0,1 mg.
7.3.3.3 Desiccator containing phosphorous pentoxide, P O .
2 5
7.3.3.4 Glazed porcelain or platinum crucible.
7.3.4 Procedure
After determining the mass (m ) from the determination of the loss on ignition at (500 ± 25) °C (7.2.5),
heat the sample at (1 050 ± 25) °C for 3 h. Cover the crucible after removing it from the furnace to
prevent carbon dioxide and water vapour in the atmosphere from being absorbed. Cool in the
desiccator and reweig
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