Bsi bs en 14664 2004

BRITISH STANDARD

Chemicals used for
treatment of water
intended for human
consumption —
Iron(III) sulfate, solid

The European Standard EN 14664:2004 has the status of a
British Standard

ICS 71.100.80

12&23<,1*:,7+287%6,3(50,66,21(;&(37$63(50,77('%<&23<5,*+7/$:

BS EN
14664:2004


BS EN 14664:2004

National foreword
This British Standard is the official English language version of
EN 14664:2004.
The UK participation in its preparation was entrusted to Technical Committee
CII/59, Chemicals for drinking water treatment, which has the responsibility
to:
—

aid enquirers to understand the text;

—

present to the responsible European committee any enquiries on the
interpretation, or proposals for change, and keep the UK interests
informed;

—

monitor related international and European developments and
promulgate them in the UK.

A list of organizations represented on this committee can be obtained on
request to its secretary.
Cross-references
The British Standards which implement international or European
publications referred to in this document may be found in the BSI Catalogue
under the section entitled “International Standards Correspondence Index”, or
by using the “Search” facility of the BSI Electronic Catalogue or of
British Standards Online.
This publication does not purport to include all the necessary provisions of a
contract. Users are responsible for its correct application.
Compliance with a British Standard does not of itself confer immunity
from legal obligations.

Summary of pages
This document comprises a front cover, an inside front cover, the EN title page,
pages 2 to 39 and a back cover.
The BSI copyright notice displayed in this document indicates when the
document was last issued.

Amendments issued since publication
This British Standard was
published under the authority
of the Standards Policy and
Strategy Committee on
24 November 2004
© BSI 24 November 2004

ISBN 0 580 44867 3

Amd. No.

Date

Comments


EN 14664

EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM

November 2004

ICS 71.100.80

English version

Chemicals used for treatment of water intended for human

consumption - Iron (III) sulfate, solid
Produits chimiques utilisés pour le traitment de l'eau
destinée à la consommation humaine - Sulfate de fer (III)
solide

Produkte zur Aufbereitung von Wasser für den meschlichen
Gebrauch - Eisen(III)sulfat, fest

This European Standard was approved by CEN on 30 September 2004.
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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36

© 2004 CEN

All rights of exploitation in any form and by any means reserved
worldwide for CEN national Members.

B-1050 Brussels

Ref. No. EN 14664:2004: E


EN 14664:2004 (E)

Contents
Page
Foreword..............................................................................................................................................................3
1

Scope ......................................................................................................................................................5

2

Normative references ............................................................................................................................5

3

Description .............................................................................................................................................5

4

Purity criteria..........................................................................................................................................7

5

Test methods..........................................................................................................................................8

6

Labelling - Transportation - Storage..................................................................................................10

Annex A (informative) General information on iron (III) sulfate solid ..........................................................13
Annex B (normative) General rules relating to safety ...................................................................................18
Annex C (normative) Analytical methods .......................................................................................................19
Annex D (informative) Reduction of Fe (III) on a silver column....................................................................35
Annex E (informative) Determination of cadmium, chromium, nickel and lead (inductively coupled
plasma optical emission spectrometry (ICP/OES)) ..........................................................................37
Bibliography ......................................................................................................................................................39

2


EN 14664:2004 (E)

Foreword
This document (EN 14664:2004) has been prepared by Technical Committee CEN/TC 164 “Water supply”, the
secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by May 2005, and conflicting national standards shall be withdrawn at the latest by
May 2005.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark,
Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

3

EN 14664:2004 (E)

Introduction
In respect of potential adverse effects on the quality of water intended for human consumption, caused by the
product covered by this document:
a)

This document provides no information as to whether the product may be used without restriction in any of the
Member States of the EU or EFTA;

b)

It should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations
concerning the use and/or the characteristics of this product remain in force.

NOTE
Conformity with this document does not confer or imply acceptance or approval of the product in any or the Member
States of the EU or EFTA. The use of the product covered by this document is subject to regulation or control by National
Authorities.

4


EN 14664:2004 (E)

1

Scope

This standard is applicable to iron (III) sulfate solid used for treatment of water intended for human consumption. It
describes the characteristics of iron (III) sulfate solid and specifies the requirements and the corresponding
analytical methods for iron (III) sulfate solid (analytical methods are given in Annex C) and gives information on its
use in water treatment. It also determines the rules relating to safe handling and use of iron (III) sulfate solid (see
Annex B).

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.
EN ISO 3696, Water for analytical laboratory use – Specification and test methods (ISO 3696:1987)
ISO 3165, Sampling of chemical products for industrial use – Safety in sampling
ISO 5790:1979, Inorganic chemical products for industrial use – General method for the determination of chloride
content - Mercurimetric method
ISO 6206, Chemical products for industrial use – Sampling - Vocabulary
ISO 8213, Chemical products for industrial use – Sampling techniques – Solid chemical products in the form of
particles varying from powders to coarse lumps

3

Description

3.1

Identification

3.1.1

Chemical name

Iron (III) sulfate solid.
3.1.2

Synonym or common names

Ferric sulfate solid.
3.1.3

Relative molecular mass

561,9.
3.1.4

Empirical formula

Fe2(SO4)3. x H2O where x is approximately 5,5.
3.1.5

Chemical formula

Fe2(SO4)3. x H2O where x is approximately 5,5.

5


EN 14664:2004 (E)

3.1.6

CAS Registry Number 1)

10028-22-5.
3.1.7

EINECS reference 2)

233-072-9.

3.2

Commercial form

The iron (IlI) sulfate solid is available as free flowing granules or powder, with a particle size range from 0,1 mm to
10 mm and 0,055 mm to 0,060 mm respectively and the angle of repose is approximately 37.

3.3

Physical properties

3.3.1

Appearance

The iron (III) sulfate solid consists of greyish or yellowish granules.
3.3.2

Density

The bulk density is approximately equal to 1 300 kg/m3 for granules and 1 000 kg/m3 for powders at 20 °C.
3.3.3

Solubility (in water)

Iron (III) sulfate solid dissolves rapidly in water. The solubility is approximately 550 g/l, corresponding to
approximately mass fraction 11 % of Fe at 20 °C. At concentrations lower than mass fraction of 0,3 % Fe,
hydrolysis and formation of iron (III) hydroxide will occur.
3.3.4

Vapour pressure

Not known.
3.3.5

Boiling point at 100 kPa 3)

Not applicable.
3.3.6

Melting point

Iron (IIl) sulfate solid decomposes when heated.
3.3.7

Specific heat

Not known.
3.3.8

Viscosity (dynamic)

Not applicable.

1)

Chemical Abstract Service Registry Number.

2)

European Inventory of Existing Commercial Chemical Substances.

3)

100 kPa = 1 bar.

6


EN 14664:2004 (E)

3.3.9

Critical temperature

Not applicable.
3.3.10 Critical pressure
Not applicable.
3.3.11 Physical hardness

The granule strength is higher than 50 N.

3.4

Chemical properties

Iron (III) sulfate solid is slightly hygroscopic at relative humidity higher than 50 %.
Iron (III) sulfate solutions are acidic.

4
4.1

Purity criteria
General

This document specifies the minimum purity requirements for iron (III) sulfate solid used for the treatment of water
intended for human consumption. Limits are given for impurities commonly present in the product. Depending on
the raw material and the manufacturing process other impurities may be present and, if so, this shall be notified to
the user and when necessary to relevant authorities.
NOTE
Users of this product should check the national regulations in order to clarify whether it is of appropriate purity for
treatment of water intended for human consumption, taking into account raw water quality, required dosage, contents of other
impurities and additives used in the product not stated in this product standard.

Limits have been given for impurities and chemical parameters where these are likely to be present in significant
quantities from the current production process and raw materials. If the production process or raw materials lead to
significant quantities of impurities, by-products or additives being present, this shall be notified to the user.

4.2

Composition of commercial product

The product shall contain not less than mass fraction of 64 % of Fe2(SO4)3 or not less than a mass fraction of 18 %
of Fe and shall be within ± 3 % of the manufacturer's declared values.

4.3

Impurities and main by-products

The product shall conform to the requirements specified in Table 1.
The concentration limits refer to Fe (III).

7


EN 14664:2004 (E)

Table 1 – Impurities
Impurity

Limit
Mass fraction in % of Fe (III) content
Grade 1

Manganese
Iron(II)

a

H2SO4 free

Insoluble matters
a

b

Grade 2

Grade 3

max.

0,5

1

2

max.

3,5

3,5

3,5

max.

8

8

8

max.

10

10

10

Fe (II) has a lower coagulant efficiency compared to Fe (III).

Also hydrolysis of Fe (II) starts at pH value 8, and therefore Fe (II) can remain into
the water at lower pH values
b

An excess of insoluble matters indicates the presence of foreign matter. Iron is
a component of the product will usually be removed in the treatment process.

4.4

Chemical parameters

The product shall conform to the requirements specified in Table 2.
The concentration limits are specified in milligrams per kilogram of Fe (III).
Table 2 – Chemical parameters
Limit in
Parameter

mg/kg of Fe (III)
Type 1

Type 2

Type 3

Arsenic (As)

max.

1

20

50

Cadmium (Cd)

max.

1

25

50

Chromium (Cr)

max.

350

500

Mercury (Hg)

max.

5

10

Nickel (Ni)

max.

300

350

500

Lead (Pb)

max.

2,5

100

400

Antimony (Sb)

max.

10

20

60

Selenium (Se)

max.

5

20

60

100
2,5

NOTE
Cyanide (CN-) is usually not relevant because of the acidity of the
product. Pesticides and polycyclic aromatic hydrocarbons are not relevant since
the raw materials used in the manufacturing process are free of them.

For maximum impact of iron (III) sulfate on trace metal content in drinking
water see A.2.

5
5.1

Test methods
Sampling

Observe the general recommendations in ISO 3165 and take into account ISO 6206. Prepare the laboratory
sample required by the relevant procedure described in ISO 8213.

8


EN 14664:2004 (E)

5.2

Analyses

5.2.1

Main product

Iron (III) sulfate is determined as Fe (III) contents in the test sample. Fe (III) content is determined as the difference
between total iron content and Fe (II) content (see C.1).
5.2.2

Impurities

5.2.2.1

Manganese

The manganese content shall be determined by flame atomic absorption spectrometry (FAAS) (see C.2).
5.2.2.2

Iron (II) ( Fe (II))

The Fe (II) content is expressed as C(II) (see C.1.2.5.3).
5.2.2.3

Insoluble matter

The mass fraction in % of the insoluble matter shall be determined in accordance with the method described in C.3.
5.2.2.4

Free acid

The free acid shall be determined in accordance with the method described in C.4.
5.2.3

Chemical parameters

5.2.3.1

Preparation of sample solution

5.2.3.1.1

General

Oxidation and wet digestion is used to bring the samples into a stable solution.
5.2.3.1.2

Principle

Oxidation with hydrogen peroxide (H2O2) followed by digestion with hydrochloric acid (HCl).
5.2.3.1.3

Reagents

5.2.3.1.3.1
All reagents shall be of a recognized analytical grade and the water used shall conform to the
grade 3 specified in EN ISO 3696.
5.2.3.1.3.2

Hydrochloric acid (HCl), solution, mass fraction 30 %.

5.2.3.1.3.3

Hydrogen peroxide (H2O2), solution, mass fraction 30 %.

5.2.3.1.4

Apparatus

5.2.3.1.4.1

Ordinary laboratory apparatus and glassware together with the following

5.2.3.1.4.2

Analytical balance.

5.2.3.1.4.3

Graduated cylinder, 50 ml.

5.2.3.1.4.4

Round flask with reflux condenser.
9


EN 14664:2004 (E)

5.2.3.1.4.5

Hot plate.

5.2.3.1.4.6

Volumetric flask, 200 ml.

5.2.3.1.5

Procedure

Dissolve with 20 ml of water 20,0 g of the iron salt. Filter and wash the filter cake with hot water. Add to the mixed
filtrate and wash water 5 ml hydrogen peroxide solution (5.2.3.1.3.3) to iron (III)-samples. After adding 50 ml
hydrochloric acid (5.2.3.1.3.2) boil the solution for 15 min by using a reflux condenser (5.2.3.1.4.4). Cool down the
solution, transfer to a 200 ml volumetric flask (5.2.3.1.4.6) and fill up to the mark with water. This is the sample
solution.
5.2.3.2

Arsenic

The arsenic content shall be determined by hydride generation atomic absorption spectrometry (see C.5).
5.2.3.3

Cadmium

The cadmium content shall be determined by graphite furnace atomic absorption spectrometry (see C.7).
5.2.3.4

Chromium

The chromium content shall be determined by graphite furnace atomic absorption spectrometry (see C.7).
5.2.3.5

Mercury

The mercury content shall be determined by cold vapour atomic absorption spectrometry (see C.6).
5.2.3.6

Nickel

The nickel content shall be determined by graphite furnace atomic absorption spectrometry (see C.7).
5.2.3.7

Lead

The lead content shall be determined by graphite furnace atomic absorption spectrometry (see C.7).
5.2.3.8

Antimony

The antimony content shall be determined by hydride generation atomic absorption spectrometry (see C.5).
5.2.3.9

Selenium

The selenium content shall be determined by hydride generation atomic absorption spectrometry (see C.5).

6
6.1

Labelling - Transportation - Storage
Means of delivery

The product shall be delivered in suitable packages, paper of plastics bags, or by rubber-lined or plastics-lined bulk
truck.
In order that the purity of the product is not affected, the means of delivery shall not have been used previously for
any different product or it shall have been specially cleaned and prepared before use.

10

EN 14664:2004 (E)

Risk and safety labelling according to the EU Directives 4)

6.2

The following labelling requirements shall apply to iron (III) sulfate solid at the date of the publication of this
document.


symbols and indications of danger :


Xi : Irritant;

 Xn Harmful


nature of special risks attributed to dangerous substances:
 R 22: Harmful by ingestion;
 R 36/37/38 : Irritating to eyes, respiratory system and skin;



safety advice concerning dangerous substances:


S 26 : In case of contact with eyes, rinse immediately with plenty of water and seek medical advice;



S 28 : After contact with skin, wash immediately with plenty of water;



S 37/39 : Wear suitable gloves and eye/face protection.

NOTE
Annex I of the Directive 67/548/EEC on Classification, packaging and labelling of dangerous substances and its
amendments and adaptations in the European Union contains a list of substances classified by the EU. Substances not in this
Annex 1 should be classified on the basis of their intrinsic properties according to the criteria in the Directive by the person
responsible for the marketing of the substance.

6.3

Transportation regulations and labelling

Iron (III) sulfate solid is not listed under a UN number 5).
Iron (III) sulfate solid is not classified as a dangerous product for road, rail, sea and air transportation.

6.4

Marking

The marking shall include the following information:


name "iron(III) sulfate solid", trade name, grade and type;



net mass;



name and the address of the supplier and/or manufacturer;



statement "this product conforms to EN 14664".

6.5

Storage

6.5.1

General

Iron (III) sulfate solid is not corrosive.

4)

See [2].

5)

United Nations Number.

11


EN 14664:2004 (E)

6.5.2

Long term stability

Iron (III) sulfate solid is stable at relative humidity lower than 50 %.
6.5.3


12

Storage incompatibilities

Avoid contact with water because iron (III) sulfate solution formed is acidic and corrosive.


EN 14664:2004 (E)

Annex A
(informative)
General information on iron (III) sulfate solid

A.1 Origin
A.1.1 Raw materials
The product is manufactured from sulfuric acid, iron (II) sulfate and oxygen.

A.1.2 Manufacturing process
Iron (III) sulfate solid is produced by dissolving iron (II) sulfate in sulfuric acid with oxygen as oxidant at elevated
temperature followed by granulation or as powder produced by atomized drier of liquid iron (III) sulfate.

A.2 Quality of commercial product
The three types of iron (III) sulfate solid specified in Table 2 reflect the quality of commercially available products.
Figures A.1 to A.3 show the maximum concentrations of trace metals that would be added to the raw water by the
addition of products corresponding to the purity levels specified in Table 2. It can be seen that the concentrations of
metal added are well below the Parametric Values given in the EU Directive 98/83/EC (see [1]) at typical product
doses. Furthermore, the figures overstate the concentration of metals that would be present in the treated water
since a substantial proportion of the trace metals will be incorporated in the sludge. Users of this product should
select an appropriate grade an Type to enable them to achieve treated water quality targets taking into account raw
water characteristics, required dosage, process plant conditions and other relevant factors.

13


EN 14664:2004 (E)

Element

Drinking
water limit
ug/l

As
Cd

10
5

Cr
Hg

50
1

Ni
Pb

20
10

Sb
Se

5
10

Key
1

Maximum addition to water µg/l metal

2

Product dosage mg/l Fe – Typical dose

Figure A.1 – Maximum impact of iron (III) sulfate solid, Type 1, on trace metal content of water

14


EN 14664:2004 (E)

Element

Drinking
water limit
ug/l

As

10

Cd

5

Cr

50

Hg

1

Ni

20

Pb

10

Sb
Se

10

5

Key
1

Maximum addition to water µg/l metal

2

Product dosage mg/l Fe – Typical dose

Figure A.2 – Maximum impact of iron (III) sulfate solid, Type 2, on trace metal content of water

15


EN 14664:2004 (E)

Element

Drinking
water limit
ug/l

As

10

Cd
Cr

5
50

Hg
Ni

1
20

Pb
Sb

10
5

Se

10

Key
1

Maximum addition to water µg/l metal

2

Product dosage mg/l Fe – Typical dose

Figure A.3 – Maximum impact of iron (III) sulfate solid, Type 3, on trace metal content of water

16


EN 14664:2004 (E)

A.3 Use
A.3.1 Function
The product is used as primary coagulant.

A.3.2 Form in which it is used
The product in used as delivered or dissolved in water.

A.3.3 Treatment dose
The treatment dose is variable depending on raw water quality and corresponds to a treatment dose between
4 g/m3 and 10 g/m3 expressed as Fe.

A.3.4 Means of application
Product can be dosed continuously from a silo by a dry feeder into a solution tank for continuously overflowing into
the raw water. To promote a rapid dispersion a high turbulence at the point of addition is desirable. Iron (III) sulfate

solution is acidic and equipments in contact with the solution therefore should be made of corrosion resistant
materials (stainless, plastics, rubber, lead etc).

A.3.5 Secondary effects
Increase of the sulfate content. Reduction of alkalinity and pH value.

A.3.6 Removal of excess product
The coagulation process includes the hydrolysis of the ferric ions to ferric hydroxide. This precipitate is removed by
sedimentation, flotation and/or finally filtration.

17


EN 14664:2004 (E)

Annex B
(normative)
General rules relating to safety

B.1 Rules for safe handling and use
The supplier shall provide current safety instructions.

B.2 Emergency procedures
B.2.1 First aid
In case of contact with skin, wash with plenty of water.
In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
If swallowed, provided patient is conscious, wash out the mouth with water and mass fraction of 5 % sodium
bicarbonate solution and give a demulcent such as milk. Seek medical advice immediately

B.2.2 Spillage

Small spillage: wash away with large quantities of water.
Large spillage: neutralize with lime or soda ash, then dispose of according to local regulations. Water can be used
if washings can go to drain. Immediately inform police and local authorities if product has entered public drains or
waterways.

B.2.3 Fire
Product is not combustible. However, in contact with metals, iron (III) sulfate can liberate the flammable gas
hydrogen.

18