1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-20447-1 SANS 50896:2007Edition 1EN 896:2005Edition 2SOUTH AFRICAN NATIONAL STANDARD Chemicals used for treatment of water intended for hum
4、an consumption Sodium hydroxide This national standard is the identical implementation of EN 896:2005 and is adopted with the permission of CEN, rue de Stassart 36, B-1050 Brussels. Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax:
5、 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 50896:2007 Edition 1 EN 896:2005 Edition 2 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Committee StanSA TC 5140.19, Water, in accordance with proced
6、ures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This SANS document was published in September 2007. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 896 June 2005 ICS 71.100.80 Supersedes EN 896:1998 English version Chemicals used for treatment of water inten
7、ded for human consumption - Sodium hydroxide Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Hydroxyde de sodium Produkte zur Aufbereitung von Wasser fr den menschlichen Gebrauch - Natriumhydroxid This European Standard was approved by CEN on 12 May 2005. CEN
8、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 appli
9、cation 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 t
10、he 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, Slova
11、kia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reserved worldwid
12、e for CEN national Members. Ref. No. EN 896:2005: ESANS 50896:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Description .5 Figure 1-Solubilit
13、y of sodium hydroxide7 4 Purity criteria8 Table 1 Impurities.9 Table 2 Chemical parameters .10 5 Test methods10 6 Labelling Transportation Storage 12 Annex A (informative) General information on sodium hydroxide 15 Annex B (normative) Analytical methods .16 Table B.1 - Calibration solutions.19 Table
14、 B.2 - Concentration range .20 Table B.3 - Parameters and operating conditions of the spectrometer 21 Table B.4 - Calibration solutions for the different elements 22 Table B.5 - Wavelength per element .23 Annex C (normative) General rules relating to safety26 Bibliography 27 SANS 50896:2007This s ta
15、ndard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 3 Foreword This European Standard (EN 896:2005) has been prepared by Technical Committee CEN/TC 164 “Water supply”, the secretariat of which is held by AFNOR. This European Standard shall
16、 be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 2005, and conflicting national standards shall be withdrawn at the latest by December 2005. This document supersedes EN 896:1998. Significant technical differences bet
17、ween this edition and EN 896:1998 are as follows: a) deletion of the reference to EU Directive 80/778/EEC of July, 15 1980 in order to take into account the latest Directive in force (see 1); b) replacement of ISO 5666-1 by EN 1483. According to the CEN/CENELEC Internal Regulations, the national sta
18、ndards 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,
19、Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. SANS 50896:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 4 Introduction In respect of potential adverse effects on the quality of water intended for huma
20、n consumption, caused by the product covered by this European Standard: a) this European Standard 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 Eur
21、opean criteria, existing national regulations concerning the use and/or the characteristics of this product remain in force. NOTE Conformity with this European Standard 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 produc
22、t covered by this European Standard is subject to regulation or control by National Authorities. SANS 50896:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 5 1 Scope This European Standard is applicable to sodium hydroxide
23、 used for treatment of water intended for human consumption. It describes the characteristics and specifies the requirements and the corresponding test methods for sodium hydroxide. It gives information on its use in water treatment. It also determines the rules relating to safe handling and use (se
24、e Annex C). 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 1483:1997,
25、Water quality Determination of mercury EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696:1987) ISO 979; Sodium hydroxide for industrial use - Method of assay ISO 3165, Sampling of chemical products for industrial use Safety in sampling ISO 3196; Sodium hydroxi
26、de for industrial use- Determination of carbonates content- Titrimetric 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
27、 Description 3.1 Identification 3.1.1 Chemical name Sodium hydroxide. 3.1.2 Synonym or common name Caustic soda. 3.1.3 Relative molecular mass 40,0. 3.1.4 Empirical formula NaOH. 3.1.5 Chemical formula NaOH. SANS 50896:2007This s tandard may only be used and printed by approved subscription and free
28、mailing clients of the SABS .EN 896:2005 (E) 6 3.1.6 CAS Registry Number1)1310-73-2. 3.1.7 EINECS reference2)215-185-5. 3.2 Commercial forms The product is available as flakes, pearls, solid, or as an aqueous solution of different concentrations. 3.3 Physical properties 3.3.1 Appearance Solid: the p
29、roduct is white, deliquescent. Liquid: the product is a clear solution, slightly turbid colourless solution, slightly viscous. 3.3.2 Density Solid : the density of this product is 2,1 g/cm3. The bulk density of pearls is 1,2 kg/dm3.Liquid : the density of solution is 1,52 g/ml for a product concentr
30、ation of mass fraction of 50 % at 20 C. 3.3.3 Solubility in water The product is highly soluble at all temperatures above 20 C (partial crystallization occurs above concentration of mass fraction of 55 %, (see Figure 1). 1) Chemical Abstracts Service Registry Number. 2) European Inventory of Existin
31、g Commercial Chemical Substances. SANS 50896:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 7 Key 1-Temperature in C. 2-NaOH concentration in mass fraction in % Figure 1-Solubility of sodium hydroxide 3.3.4 Vapour pressur
32、e Solution of concentration of mass fraction of 50 % - 120 Pa at 20 C; - 450 Pa at 40 C; - 5 000 Pa at 80 C. 3.3.5 Boiling point at 100 kPa3)145 C for a solution of concentration of mass fraction of 50 %. 3) 100 kPa = 1 bar. SANS 50896:2007This s tandard may only be used and printed by approved subs
33、cription and freemailing clients of the SABS .EN 896:2005 (E) 8 3.3.6 Crystallization point + 12 C for a solution of concentration of mass fraction of 50 % (see Figure 1). 3.3.7 Specific heat 3 220 J/(kg K) at 20 C for a solution of concentration of mass fraction of 50 %. 3.3.8 Viscosity (dynamic) F
34、or a solution of concentration of mass fraction of 50 %: - 100 Pa.s at 20 C; - 25 Pa.s at 40 C; - 5 Pa.s at 80 C. 3.3.9 Critical temperature Not applicable. 3.3.10 Critical pressure Not applicable. 3.3.11 Physical hardness Not applicable. 3.4 Chemical properties The solutions of sodium hydroxide are
35、 strongly alkaline. Dilution of sodium hydroxide is very exothermic. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for sodium hydroxide used for the treatment of water intended for human consumption. Limits are given for impurities commonly present in
36、 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 a
37、ppropriate 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 products not stated in this product standard. Limits have been given for impurities and chemical parameters where th
38、ese are likely to be present in significant quantities from the current production process and raw materials. If the production process or raw materials leads to significant quantities of impurities, by-products or additives being present, this shall be notified to the user. SANS 50896:2007This s ta
39、ndard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:2005 (E) 9 4.2 Composition of commercial product The product shall contain not less than a mass fraction of 96 % of NaOHfor the solid form. Typical concentration for solutions of sodium hydroxide
40、is either a mass fraction of 50 % or 30 % , and shall be in any case within the manufacturers stated tolerance. 4.3 Impurities and main by-products The product shall conform to the requirements specified in Table 1. The concentration limits refer to pure NaOH mass fraction of 100 %. Table 1 Impuriti
41、es Impurity Limit in mass fraction in % of NaOH Sodium chloride (NaCl)a)max. 2,4 Sodium carbonate (Na2CO3)b)max. 0,4 Sodium chlorate (NaClO3)c)max. 0,7 a) Too high concentrations can cause problems with some ion exchange resins. b) Sodium carbonate is formed in contact with atmospheric carbon dioxid
42、e. c) The presence of any oxidizing agent in sodium hydroxide is to be avoided. 4.4 Chemical parameters The product shall conform to the requirements specified in Table 2. SANS 50896:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .EN 896:
43、2005 (E) 10 Table 2 Chemical parameters Parameter Limit in mg/kg of NaOH Type 1 Type 2 Arsenic (As) max. 2 10 Cadmium (Cd) max. 1 5 Chromium (Cr) max. 1 10 Mercury (Hg) max. 0,1 1 Nickel (Ni) max. 2 10 Lead (Pb) max. 5 20 Antimony (Sb) max. 5 5 Selenium (Se) max. 5 5 NOTE Cyanides, pesticides and po
44、lycyclic aromatic hydrocarbons are not relevant in sodium hydroxide. For parametric values of sodium hydroxide on trace metal content in drinking water, see 1. 5 Test methods 5.1 Sampling Prepare the laboratory sample (s) required by the relevant procedure described in ISO 8213, observe the recommen
45、dations of ISO 3165 and also take into account ISO 6206. The nature of caustic alkalis requires special care at all points of sampling and preparation for analysis. Sampling techniques shall be such as to limit or prevent atmospheric exposure since sodium hydroxides, either as aqueous solutions or a
46、s anhydrous products, rapidly absorb moisture and carbon dioxide (and other acid gases) from the atmosphere. Additional precautions are necessary if trace constituents are to be determined. NOTE For sampling liquids see 3. SANS 50896:2007This s tandard may only be used and printed by approved subscr
47、iption and freemailing clients of the SABS .EN 896:2005 (E) 11 5.2 Analyses 5.2.1 Main product 5.2.1.1 Total alkalinity The total alkalinity shall be determined by titration with an acid standard volumetric solution in accordance with ISO 979. 5.2.1.2 Caustic alkalinity The caustic alkalinity equals
48、 the total alkalinity as NaOH (see 5.2.1.1) minus the alkalinity as Na2CO3multiplied by 0,755 determined in accordance with ISO 3196. 5.2.2 Impurities 5.2.2.1 Sodium chloride The sodium chloride content shall be determined by potentiometric titration with silver nitrate solution (see B.1). 5.2.2.2 S
49、odium carbonate The sodium carbonate content shall be determined by the titrimetric method, in accordance with ISO 3196. 5.2.2.3 Sodium chlorate The sodium chlorate content shall be determined by ionic chromatography (see B.2). 5.2.3 Chemical parameters 5.2.3.1 Principle The elements antimony, arsenic, cadmium, chromium, lead, nickel and selenium are determined by inductively coupled plasma optical emission spectrometry. Mercury is determined by cold vapour atomic absorption spectrometry. 5.2.3.2 Arsenic The arsenic content sh
