1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12174:2013Chemicals used for treatmentof water intended for humanconsumption SodiumhexafluorosilicateBS EN 12174:2013 BRITISH STANDARDNational forewordThis British Standard
2、 is the UK implementation of EN 12174:2013. Itsupersedes BS EN 12174:2006 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/59, Chemicals for drinking water treatment.A list of organizations represented on this committee can beobtained on request to i
3、ts secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 80009 2ICS 13.060.20; 71.100.80Compliance with a British
4、 Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 June 2013.Amendments issued since publicationDate Text affectedBS EN 12174:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12174
5、 May 2013 ICS 71.100.80 Supersedes EN 12174:2006English Version Chemicals used for treatment of water intended for human consumption - Sodium hexafluorosilicate Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Hexafluorosilicate de sodium Produkte zur Aufbereit
6、ung von Wasser fr den menschlichen Gebrauch - Natriumhexafluorsilikat This European Standard was approved by CEN on 28 March 2013. 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 stand
7、ard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in an
8、y 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 Repu
9、blic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN
10、 COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12174:2013: EBS EN 12174:2013EN
11、12174:2013 (E) 2 Contents Page Foreword . 3 Introduction 4 1 Scope 5 2 Normative references . 5 3 Description . 5 3.1 Identification . 5 3.2 Commercial form 6 3.3 Physical properties 6 3.4 Chemical properties . 7 4 Purity criteria 7 4.1 General . 7 4.2 Composition of commercial product . 7 4.3 Impur
12、ities and main by-products 7 4.4 Chemical parameters . 8 5 Test methods 8 5.1 Sampling . 8 5.2 Analyses . 8 6 Labelling - Transportation - Storage . 14 6.1 Means of delivery . 14 6.2 Labelling according to the EU legislation 14 6.3 Transportation regulations and labelling 14 6.4 Marking . 15 6.5 Sto
13、rage . 15 Annex A (informative) General information on sodium hexafluorosilicate 16 A.1 Origin 16 A.2 Use 16 Annex B (normative) General rules relating to safety . 17 B.1 Rules for safe handling and use 17 B.2 Emergency procedures 17 Bibliography 18 BS EN 12174:2013EN 12174:2013 (E) 3 Foreword This
14、document (EN 12174:2013) 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 November 201
15、3, and conflicting national standards shall be withdrawn at the latest by November 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent right
16、s. This document supersedes EN 12174:2006. Significant differences between this edition and EN 12174:2006 are as follows: the replacement of warning and safety precautions notes by labelling according to Regulation (EC) No 1272/2008. According to the CEN-CENELEC Internal Regulations, the national st
17、andards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
18、 Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 12174:2013EN 12174:2013 (E) 4 Introduction In respect of potential adverse effects on the quality of water intended for human consumption, caused b
19、y 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 regulat
20、ions 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 of the Member States of the EU or EFTA. The use of the product covered by this document is subject to regulatio
21、n or control by National Authorities. BS EN 12174:2013EN 12174:2013 (E) 5 1 Scope This European Standard is applicable to sodium hexafluorosilicate used for treatment of water intended for human consumption. It describes the characteristics of sodium hexafluorosilicate and specifies the requirements
22、 and the corresponding test methods for sodium hexafluorosilicate. It gives information on its use in water treatment. It also determines the rules relating to safe handling and use of sodium hexafluorosilicate (see Annex B). 2 Normative references The following documents, in whole or in part, are n
23、ormatively 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. EN ISO 3696:1995, Water for analytical laboratory use Spec
24、ification and test methods (ISO 3696:1987) ISO 3165, Sampling of chemical products for industrial use Safety in sampling ISO 4281, Sodium hexafluorosilicate for industrial use Determination of free acidity and total hexafluorosilicate content Titrimetric method ISO 4793, Laboratory sintered (fritted
25、) filters Porosity grading, classification and designation ISO 5444, Sodium fluorosilicate for industrial use Determination of loss in mass at 105 degrees C ISO 5993, Sodium hydroxide for industrial use Determination of mercury content Flameless atomic absorption spectrometric method ISO 6206, Chemi
26、cal products for industrial use Sampling Vocabulary ISO 6353-1, Reagents for chemical analysis Part 1: General test methods 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 Ident
27、ification 3.1.1 Chemical name Disodium hexafluorosilicate. 3.1.2 Synonym or common name Sodium silicofluoride, sodium hexafluorosilicate. 3.1.3 Relative molecular mass 188,055. 3.1.4 Empirical formula Na2SiF6. BS EN 12174:2013EN 12174:2013 (E) 6 3.1.5 Chemical formula Na2SiF6. 3.1.6 CAS-Registry Num
28、ber1)16893-85-9. 3.1.7 EINECS reference2)240-934-8. 3.2 Commercial form The product is a crystalline powder. 3.3 Physical properties 3.3.1 Appearance and odour The product is a colourless, odourless fine crystalline powder. 3.3.2 Density The particle density of the crystals is 2,8 g/cm3at 20 C. The
29、bulk density of the product is approximately 1,5 g/cm3at 20 C. 3.3.3 Solubility The solubility of the product in water is 7 g/l at 20 C. 3.3.4 Vapour pressure Not applicable. 3.3.5 Boiling point at 100 kPa3)Not applicable. 3.3.6 Crystallisation point The product melts above 500 C. 3.3.7 Specific hea
30、t Not known. 1)Chemical Abstracts Service Registry Number. 2)European Inventory of Existing Commercial Chemical Substances. 3) 100 kPa = 1 bar. BS EN 12174:2013EN 12174:2013 (E) 7 3.3.8 Viscosity, dynamic Not applicable. 3.3.9 Critical temperature Not applicable. 3.3.10 Critical pressure Not applica
31、ble. 3.3.11 Physical hardness Not applicable. 3.4 Chemical properties The pH value of a saturated aqueous solution (7 g/l) of sodium hexafluorosilicate is approximately 10. Sodium hexafluorosilicate reacts with acids to form hydrofluoric acid. 4 Purity criteria 4.1 General This document specifies th
32、e minimum purity requirements for sodium hexafluorosilicate 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 s
33、hall be notified to the user and when necessary to relevant authorities. 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,
34、contents of other impurities and additives used in the products not stated in this document. Limits have been given for impurities and chemicals parameters where these are likely to be present in significant quantities from the current production process and raw materials. If the production process
35、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 content of sodium hexafluorosilicate shall not be less than a mass fraction of 98 % (Na2SiF6). The concentration of sod
36、ium hexafluorosilicate shall be within 5 % of the manufacturers declared value. 4.3 Impurities and main by-products The product shall conform to the requirements specified in Table 1. Table 1 Impurities Impurity Limit in mass fraction in % of commercial product Water- insoluble matter max.0,5 Moistu
37、re max. 0,3 BS EN 12174:2013EN 12174:2013 (E) 8 4.4 Chemical parameters The product shall conform to the requirements specified in Table 2. Table 2 Chemical parameters Parameter Limit mg/kg of commercial product Antimony (Sb) max. 80 Arsenic (As) max. 400 Cadmium (Cd) max. 40 Chromium (Cr) max. 400
38、Lead (Pb) max. 400 Mercury (Hg) max. 10 Nickel (Ni) max. 400 Selenium (Se) max. 80 NOTE Other chemical parameters and indicator parameters are not relevant in sodium hexafluorosilicate because the raw materials used in the manufacturing process are free of them. For parametric values of sodium hexaf
39、luorosilicate on trace metal content in drinking water, see 1. 5 Test methods 5.1 Sampling Observe the general recommendations of ISO 3165 and take account of ISO 6206. Prepare the laboratory sample(s) required by the relevant procedure described in ISO 8213. NOTE Sodium hexafluorosilicate presents
40、a toxic hazard through inhalation of dust (see B.1). 5.2 Analyses 5.2.1 Main product The sodium hexafluorosilicate content shall be determined in accordance with ISO 4281. This standard includes the determination of free acid. 5.2.2 Impurities 5.2.2.1 Insoluble matters 5.2.2.1.1 Procedure Weigh and
41、transfer to a beaker 2 g of the sample, which has previously been dried at 105 C to constant mass. Dissolve in 500 ml of hot water. Generally, 15 min to 30 min is sufficient time. BS EN 12174:2013EN 12174:2013 (E) 9 Filter through a tared Gooch crucible or a tared fritted-glass filter of medium poro
42、sity (porosity P 16 according to ISO 4793). Wash with at least six separate 25 ml portions of boiling water, allowing the crucible to drain between washings. Dry the crucible or filter at 105 C to constant mass. 5.2.2.1.2 Expression of results The content of insoluble matters, W1, expressed as mass
43、fraction in % is given by the following formula: 112100mWm= x (1) where m1is the mass, in grams, of the filter residue; m2is the mass, in grams, of the test portion. 5.2.2.2 Moisture content The content of moisture shall be determined in accordance with ISO 5444. 5.2.3 Chemical parameters 5.2.3.1 Ge
44、neral The content of chemical parameters shall be determined using the procedures specified in Table 3. Table 3 Procedures for the determination of chemical parameters Element Reference Method Wavelength nm Flame As See 5.2.3.3 Hydride AAS 193,7 n.a Sb See 5.2.3.3 Hydride AAS 217,6 n.a Cd ISO 6353-1
45、, MG 29 See 5.2.3.2 AAS 228,8 air-acetylene Cr ISO 6353-1, MG 29 See 5.2.3.2 AAS 357,8 air-acetylene Pb ISO 6353-1, MG 29 See 5.2.3.2 AAS 217,0 or 283,3 air-acetylene Ni ISO 6353-1, MG 29 See 5.2.3.2 AAS 232,0 Oxidising Air-acetylene Se See 5.2.3.3 Hydride AAS 196,0 n.a Hg In accordance with ISO 599
46、3 flameless AAS 253,6 n.a n.a. not applicable. AAS Atomic absorption spectrometry. BS EN 12174:2013EN 12174:2013 (E) 10 5.2.3.2 Determination of cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) 5.2.3.2.1 Principle The elements cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) are determin
47、ed using atomic absorption spectrometry with standard additions method in taking account of ISO 6353-1. 5.2.3.2.2 Reagents All reagents shall be of a recognised analytical grade and the water used shall conform to the grade 3 specified in EN ISO 3696:1995. 5.2.3.2.2.1 Standard solution (100 g/l Cd,
48、Cr, Pb or Ni) The standard solution shall be freshly prepared on the day of use by individual dilution of a stock solution. This stock solution with a Cd, Cr, Pb or Ni content of at least 1 mg/l shall be made by dilution of standard solutions of Cd, Cr, Pb and Ni, which are available from all major
49、suppliers of laboratory chemicals. This stock solution shall be kept in containers of tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polytetrafluoroethylene (PTFE) or polyethylene (PE). The stock solution should not be kept for longer than four weeks. 5.2.3.2.3 Apparatus Ordinary laboratory apparatus and the following: 5.2.3.2.3.1 Atomic absorption spectrometer with the measurement parameters specified in Table 3. 5.2.3.2.4 Procedure 5.2.3.2.4.1 Test portion Weigh 1 g to the nearest 0,01 mg of the laboratory sam
