1、BS EN ISO21068-3:2008ICS 81.080NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDChemical analysisof silicon-carbide-containing rawmaterials andrefractory productsPart 3: Determination of nitrogen,oxygen and metallic and oxidicconstituents (ISO 21068-3:2008)This B
2、ritish Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 30 BSI 2008ISBN 978 0 580 58093 2Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 21068-3:2008National forewordThis British Standard is the UK implementation of EN ISO21068-3:2008.The
3、UK participation in its preparation was entrusted to TechnicalCommittee RPI/1, Refractory products and materials.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Us
4、ers are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.September2008EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 21068-3August 2008ICS 81.080English VersionChemical analysis of silicon-carbide-containing raw materialsa
5、nd refractory products - Part 3: Determination of nitrogen,oxygen and metallic and oxidic constituents (ISO 21068-3:2008)Analyse chimique des matires premires et des produitsrfractaires contenant du carbure de silicium - Partie 3:Dosage de lazote, de loxygne et des constituantsmtalliques et oxyds (I
6、SO 21068-3:2008)Chemische Analyse von Siliciumcarbid enthaltendenRohstoffen und feuerfesten Erzeugnissen - Teil 3:Bestimmung des Gehaltes an Stickstoff, Sauerstoff sowiemetallischen und oxidischen Bestandteilen (ISO 21068-3:2008)This European Standard was approved by CEN on 11 July 2008.CEN members
7、are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to
8、the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same
9、status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania
10、, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldw
11、ide for CEN national Members.Ref. No. EN ISO 21068-3:2008: EBS EN ISO 21068-3:2008EN ISO 21068-3:2008 (E) 3 Foreword This document (EN ISO 21068-3:2008) has been prepared by Technical Committee ISO/TC 33 “Refractories“ in collaboration with Technical Committee CEN/TC 187 “Refractory products and mat
12、erials” the secretariat of which is held by BSI. 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 February 2009, and conflicting national standards shall be withdrawn at the latest by February 2009
13、. 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 rights. According to the CEN/CENELEC Internal Regulations, the national standards organizati
14、ons of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania
15、, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 21068-3:2008 has been approved by CEN as a EN ISO 21068-3:2008 without any modification. BS EN ISO 21068-3:2008ISO 21068-3:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv Int
16、roduction.v 1 Scope1 2 Normative references1 3 Terms and definitions .2 4 Determination of nitrogen and oxygen .2 4.1 General .2 4.2 Combined determination of nitrogen and oxygen by an analyser with thermal conductivity (CR) and infrared absorption (IR) detection.2 5 Determination of nitrogen calcul
17、ated as Si3N44 5.1 General .4 5.2 Acid decomposition Titration method5 5.3 Acid decomposition Photometry method 9 5.4 Inert-gas fusion Thermal conductivity method .12 5.5 Determination of total nitrogen17 6 Determination of free Iron by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AE
18、S)17 6.1 General .17 6.2 Copper sulfate method .18 6.3 Bromine/methanol method.19 7 Determination of free aluminium and free magnesium.22 7.1 General .22 7.2 Acid decomposition Inductively coupled plasma atomic emission spectroscopy (ICP-AES)22 7.3 Acid decomposition Flame Atomic Absorption Spectrom
19、etry (FAAS).24 7.4 Hydrogen generating method 25 8 Analysis of oxides .26 8.1 General .26 8.2 Wet methods 26 8.3 Flame atomic absorption and/or inductively coupled plasma atomic emission spectrometer26 8.4 XRF fusion method after ignition of the sample 27 8.5 Determination of silicon(IV) oxide, alum
20、inium oxide, iron(III) oxide, titanium(IV) oxide, calcium oxide, magnesium oxide, sodium oxide, potassium oxide, chromium(III) oxide, zirconium oxide, and boron oxide .29 9 Expression of results31 10 Test report31 Annex A (informative) Statistical results obtained with analysis of refractories conta
21、ining carbon and/or silicon carbide .32 Bibliography37 BS EN ISO 21068-3:2008ISO 21068-3:2008(E) iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Internat
22、ional Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with I
23、SO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical c
24、ommittees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to th
25、e possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 21068-3 was prepared by Technical Committee ISO/TC 33, Refractories. ISO 21068 consists of the following parts, under the
26、 general title Chemical analysis of silicon-carbide-containing raw materials and refractory products: Part 1: General information and sample preparation Part 2: Determination of loss on ignition, total carbon, free carbon and silicon carbide, total and free silica and total and free silicon Part 3:
27、Determination of nitrogen, oxygen and metallic and oxidic constituents BS EN ISO 21068-3:2008ISO 21068-3:2008(E) ISO 2008 All rights reserved vIntroduction ISO 21068, Parts 1 to 3, have been developed from the combination of a Japanese standard JIS 20118and work items originally developed within CEN
28、. Because there is a wide variety of laboratory equipment in use, the most commonly used methods are described. This part of ISO 21068 is applicable to the analysis of all refractory products as classified in ISO 10081 (all parts) 3, 4, 5, 6(shaped) and ISO 1927 1(unshaped) and raw materials contain
29、ing carbon and/or silicon carbide. Therefore, this part of ISO 21068 covers the full range of analysis from pure silicon carbide to oxidic refractory composition with a low content of silicon carbide and/or nitrides. Primarily, this part of ISO 21068 provides methods to distinguish between different
30、 carbon bound types like total carbon (Ctotal) and free carbon (Cfree) and derives from these two the silicon carbide content. If free carbon is present, this part of ISO 21068 includes different types of temperature treatment in order to determine the mass changes gravimetrically. Frequently, the r
31、esulting residue is used for other determinations. The determination of other groups of analytes described in this part of ISO 21068 are free metals, free silicon (Sifree), free aluminum (Alfree), free magnesium (Mgfree), free iron (Fefree) and the group of oxides from main to trace components. This
32、 part of ISO 21068 also describes the chemical analysis of SiO2, total Si, oxygen and nitrogen and other oxidic bound metals which typically occur in the materials. This part of ISO 21068 represents a listing of analytical methods which is approximately structured according to material composition.
33、However, it is still the user who should prove the applicability of the method depending on the material and analytical requirements. BS EN ISO 21068-3:2008BS EN ISO 21068-3:2008INTERNATIONAL STANDARD ISO 21068-3:2008(E) ISO 2008 All rights reserved 1Chemical analysis of silicon-carbide-containing r
34、aw materials and refractory products Part 3: Determination of nitrogen, oxygen and metallic and oxidic constituents 1 Scope This part of ISO 21068 specifies methods for the determination of total nitrogen and nitrogen calculated as silicon nitride, total oxygen, and free metallic and oxidic componen
35、ts in silicon carbide raw materials and refractory products. It applies only to silicon carbide materials that are not bonded with nitrogen. Nitride-bonded silicon carbide refractories are covered in EN 12698-1. 2 Normative references The following referenced documents are indispensable for the appl
36、ication of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 10058-1, Chemical analysis of magnesite and dolomite refractory products (alternative to the X-ray fluorescenc
37、e method) Part 1: Apparatus, reagents, dissolution and gravimetric silica ISO 10058-2, Chemical analysis of magnesite and dolomite refractory products (alternative to the X-ray fluorescence method) Part 2: Wet chemical analysis ISO 10058-3, Chemical analysis of magnesite and dolomite refractory prod
38、ucts (alternative to the X-ray fluorescence method) Part 3: Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma emission spectrometry (ICP-AES) ISO 12677, Chemical analysis of refractory products by XRF Fused cast bead method ISO 20565-1, Chemical analysis of chrome-bearing re
39、fractory products and chrome-bearing raw materials (alternative to the X-ray fluorescence method) Part 1: Apparatus, reagents, dissolution and gravimetric silica ISO 20565-2, Chemical analysis of chrome-bearing refractory products and chrome-bearing raw materials (alternative to the X-ray fluorescen
40、ce method) Part 2: Wet chemical analysis ISO 20565-3, Chemical analysis of chrome-bearing refractory products and chrome-bearing raw materials (alternative to the X-ray fluorescence method) Part 3: Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma emission spectrometry (ICP-
41、AES) ISO 21068-1:2008, Chemical analysis of silicon-carbide-containing raw materials and refractory products Part 1: General information and sample preparation BS EN ISO 21068-3:2008ISO 21068-3:2008(E) 2 ISO 2008 All rights reservedISO 21068-2:2008, Chemical analysis of silicon-carbide-containing ra
42、w materials and refractory products Part 2: Determination of loss on ignition, total carbon, free carbon and silicon carbide, total and free silica and total and free silicon ISO 21079-1, Chemical analysis of refractories containing alumina, zirconia and silica Refractories containing 5 % to 45 % of
43、 ZrO2(alternative to the X-ray fluorescence method) Part 1: Apparatus, reagents and dissolution ISO 21079-2, Chemical analysis of refractories containing alumina, zirconia and silica Refractories containing 5 % to 45 % of ZrO2(alternative to the X-ray fluorescence method) Part 2: Wet chemical analys
44、is ISO 21079-3, Chemical analysis of refractories containing alumina, zirconia and silica Refractories containing 5 % to 45 % of ZrO2(alternative to the X-ray fluorescence method) Part 3: Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma emission spectrometry (ICP-AES) ISO 2
45、1587-1, Chemical analysis of aluminosilicate refractory products (alternative to the X-ray fluorescence method) Part 1: Apparatus, reagents, dissolution and gravimetric silica ISO 21587-2, Chemical analysis of aluminosilicate refractory products (alternative to the X-ray fluorescence method) Part 2:
46、 Wet chemical analysis ISO 21587-3, Chemical analysis of aluminosilicate refractory products (alternative to the X-ray fluorescence method) Part 3: Inductively coupled plasma and atomic absorption spectrometry methods ISO 26845, Chemical analysis of refractories General requirements for wet chemical
47、 analysis, atomic absorption spectrometry (AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) methods EN 12698-1:2007, Chemical analysis of nitride bonded silicon carbide refractories Part 1: Chemical methods 3 Terms and definitions For the purposes of this document, the term
48、s and definitions given in ISO 21068-1 apply. 4 Determination of nitrogen and oxygen 4.1 General For oxygen only, the IR detection method is given; for nitrogen, several different methods are described, calculated nominally as Si3N4. NOTE The calculation of nitrogen as Si3N4is only applicable in the
49、 case where other nitride species are absent or too low to detect by XRD, see ISO 21068-1. Otherwise, nitrogen is reported as total nitrogen. 4.2 Combined determination of nitrogen and oxygen by an analyser with thermal conductivity (CR) and infrared absorption (IR) detection 4.2.1 Principle The method uses inert-gas fusion analysis. A preweighed sample is placed in a graphite crucible positioned between the electrodes of an impulse furnace. 5 kW of power (typically) is passed through t
