1、BRITISH STANDARDBS EN ISO 21078-1:2008Determination of boron (III) oxide in refractory products Part 1: Determination of total boron (III) oxide in oxidic materials for ceramics, glass and glazesICS 81.040.01; 81.060.01g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g
2、54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 21078-1:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2008 BSI 2008ISBN 978 0 580 54934 2Natio
3、nal forewordThis British Standard is the UK implementation of EN ISO 21078-1:2008. It supersedes BS 1902-2.3: Addendum No. 1:1976 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee RPI/1, Refractory products and materials.A list of organizations represen
4、ted on this committee can be obtained on request to its secretary.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 cannot confer immunity from legal obligations.Amendments/cor
5、rigenda issued since publicationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 21078-1January 2008ICS 81.040.01; 81.060.01English VersionDetermination of boron (III) oxide in refractory products - Part 1:Determination of total boron (III) oxide in oxidic materials forceramics, gl
6、ass and glazes (ISO 21078-1:2008)Dosage de loxyde de bore (III) dans les produitsrfractaires - Partie 1: Dtermination de loxyde de bore (III)total dans les matriaux oxydants pour les cramiques, lesverres et les maux (ISO 21078-1:2008)Bestimmung des Gehaltes an Bor(III)-oxid in feuerfestenErzeugnisse
7、n - Teil 1: Bestimmung des Gesamtgehaltes anBor(III)-oxid in oxidischen Werkstoffen fr Keramik, Glasund Glasuren (ISO 21078-1:2008)This European Standard was approved by CEN on 28 December 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions f
8、or 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 the CEN Management Centre or to any CEN member.This European Standard exists in three official
9、 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 status as theofficial versions.CEN members are the national standards bodies of Austria, Belgi
10、um, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STA
11、NDARDIZATIONCOMIT 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 reservedworldwide for CEN national Members.Ref. No. EN ISO 21078-1:2008: EForeword This document (EN ISO 210
12、78-1:2008) has been prepared by Technical Committee ISO/TC 33 “Refractories“ in collaboration with Technical Committee CEN/TC 187 “Refractory products and materials” the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publicatio
13、n of an identical text or by endorsement, at the latest by July 2008, and conflicting national standards shall be withdrawn at the latest by July 2008. 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 b
14、e held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Fi
15、nland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 21078-1:2008 has been approved by CEN as a
16、 EN ISO 21078-1:2008 without any modification. BS EN ISO 21078-1:2008Reference numberISO 21078-1:2008(E)INTERNATIONAL STANDARD ISO21078-1First edition2008-01-15Determination of boron(III) oxide in refractory products Part 1: Determination of total boron(III) oxide in oxidic materials for ceramics, g
17、lass and glazes BS EN ISO 21078-1:2008ii iiiContents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Preparation of the test sample 2 5 Number of determinations . 2 6 Determination of boron(III) oxide by alkaline titrimetry 3 7 Determination of boron(III) oxide b
18、y azomethine H absorption spectrophotometry. 5 8 Determination of boron(III) oxide by curcumin absorption spectrophotometry 8 9 Determination of boron(III) oxide by inductively coupled plasma atomic emission spectrometry (ICP-AES) . 12 10 Expression of test results 14 11 Test report . 15 Annex A (in
19、formative) Interlaboratory test results . 16 BS EN ISO 21078-1:2008iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO techni
20、cal 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 ISO, also take part in the work. ISO collaborates closely w
21、ith 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 committees is to prepare International Standards. Draft Int
22、ernational 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 the possibility that some of the elements of this document m
23、ay be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 21078-1 was prepared by Technical Committee ISO/TC 33, Refractories, in collaboration with Technical Committee CEN/TC 187, Refractory products and materials. ISO 21078 consists of
24、 the following parts, under the general title Determination of boron(III) oxide in refractory products: Part 1: Determination of total boron(III) oxide in oxidic materials for ceramics, glass and glazes Part 2: Acid extraction method for the determination of boron(III) oxide in binder components BS
25、EN ISO 21078-1:20081Determination of boron(III) oxide in refractory products Part 1: Determination of total boron(III) oxide in oxidic materials for ceramics, glass and glazes 1 Scope This part of ISO 21078 specifies methods of determining boron(III) oxide in refractory products and raw materials, i
26、n mass fractions of 0,01 % or greater. It is applicable to the determination of total boron(III) oxide in oxidic materials for ceramics, glass and glazes. The determination of boron(III) oxide is carried out using one of the following four methods: a) alkaline titrimetry, which is applied to samples
27、 containing more than 0,5 % by mass of boron(III) oxide; b) azomethine H absorption spectrophotometry, which is applied to samples containing from 0,01 % by mass to 2,5 % by mass of boron(III) oxide; c) curcumin absorption spectrophotometry (rothocyanine method), which is applied to samples containi
28、ng from 0,01 % by mass to 1,0 % by mass of boron(III) oxide; d) inductively coupled plasma atomic emission spectrometry (ICP-AES), which is applied to samples containing from 0,01 % by mass to 15 % by mass of boron(III) oxide. NOTE 1 The method can be extended to 30 % boron(III) oxide using modified
29、 oxidic fluxes. NOTE 2 Interlaboratory test results for this part of ISO 21078 are given in Annex A. 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 lat
30、est edition of the referenced document (including any amendments) applies. ISO 31-0, Quantities and units Part 0: General principles ISO 836, Refractories Vocabulary ISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth ISO 3696, Water for analytical labo
31、ratory use Specification and test methods ISO 6353-2, Reagents for chemical analysis Part 2: Specifications First series ISO 6353-3, Reagents for chemical analysis Part 3: Specifications Second series BS EN ISO 21078-1:20082 3 Terms and definitions For the purposes of this document, the terms and de
32、finitions given in ISO 836 and the following apply. 3.1 dry unshaped refractories dry particles and/or powder of unshaped refractories 3.2 wet unshaped refractories wet particles and/or powder of unshaped refractories with liquid such as mortar and a mixture of refractory-aggregate and pitch or resi
33、n 4 Preparation of the test sample 4.1 Refractory brick or its raw material Carry out sampling in accordance with the contract between the user and producer. Take a specified quantity from a lot of the sample and crush to pass through a 6,7 mm sieve (see ISO 3310-1). Reduce to about 100 g by rifflin
34、g or coning and quartering, then grind all the reduced sample to pass through a 300 m sieve (ISO 3310-1). 4.2 Unshaped refractories Prepare two portions of approximately 100 g each of the sample for analysis (both dry and wet) and crush to pass through a 300 m sieve (see ISO 3310-1) in accordance wi
35、th the following procedure. 4.3 Dry unshaped refractories Take one bag or 5 kg of the sample from a lot, reduce to about 100 g as described in 4.1 and crush to pass through a 300 m sieve. 4.4 Wet unshaped refractories Take a specified quantity from the sample and spread on a heat-resistant plate tha
36、t does not react with the sample (for example, a polyethylene tetrafluoride plate) to form a charge of 10 mm thickness. Dry the sample in an air-bath or oven at 110C 5C for a minimum of 10 h. Then crush to pass through a 6,7 mm sieve, reduce to about 100 g by riffling or coning and quartering, and g
37、rind to pass through a 300 m sieve (see ISO 3310-1). 4.5 Laboratory sample Reduce the laboratory sample from 4.1 or 4.2 to approximately 25 g by coning and quartering, and grind to pass through a 106 m sieve. This is the test sample for analysis. Transfer it into a container (e.g. a flat weighing bo
38、ttle (50 mm 30 mm) or sample tube (50 mm 25 mm), dry in an oven at 110C 5C for a minimum of 2 h, cool and store it in a desiccator. 4.6 Weighing of test portion Weigh the quantity of the test portion for the chemical analysis specified for the particular procedure, to the nearest 0,1 mg, using an an
39、alytical balance and record the actual mass. 5 Number of determinations Carry out simultaneous duplicate determinations. Carry out a blank test on the reagents and make appropriate deductions from the results. BS EN ISO 21078-1:200836 Determination of boron(III) oxide by alkaline titrimetry 6.1 Prin
40、ciple The sample is fused with sodium hydroxide in a dish placed in a furnace at about 600 C. After cooling, the melt is dissolved in water and the sample solution made up to about 100 ml with water. The interfering ions left in the sample solution are precipitated by adding calcium carbonate. After
41、 first adjusting the pH value to 6,5 with sodium hydroxide solution, mannitol is added and the H+ ions liberated as the result are titrated with sodium hydroxide to obtain a pH value of 6,8. 6.2 Reagents Use only reagents of known analytical purity and water conforming to the requirements of grade 2
42、 of ISO 3696 (e.g. double-distilled water). The boron and borate ion concentrations in the water and the reagents shall be negligible compared with the lowest concentration to be determined. All solutions are aqueous, unless otherwise specified. 6.2.1 Sodium hydroxide (ISO 6353-2 R 34), assay, minim
43、um mass fraction 98 %. 6.2.2 Hydrochloric acid (concentrated), (ISO 6353-2 R 13), mass fraction 35 %. 6.2.3 Hydrochloric acid (1+1), add 1 volume of hydrochloric acid (concentrated) to 1 volume of water. 6.2.4 Calcium carbonate (ISO 6353-3 R 53), assay, minimum mass fraction 99,5 %. 6.2.5 Bromocreso
44、l purple solution, C21H16Br2O5S, 1 g/l. Dissolve 0,1 g of bromocresol purple in water and dilute to approximately 100 ml. Keep this solution in the dark at low temperature. 6.2.6 Boron(III) oxide standard solution, 0,1 mg B2O3/ml. Transfer approximately 0,5 g of boric acid into a 100 ml beaker, spre
45、ad it as a thin layer and dry for 24 h in a desiccator. Weigh 0,177 6 g of this dry boric acid and transfer into a 200 ml plastic beaker. Dissolve in approximately 100 ml of water and dilute precisely to 1 000 ml in a volumetric flask. 6.2.7 D()-mannitol, C6H14O6. 6.2.8 Sodium hydroxide standard vol
46、umetric solution. Transfer 50 g of sodium hydroxide into a polyethylene bottle, add 50 ml of water, and dissolve with cooling. Allow to stand for several days with a cover, pipette 4,0 ml of the supernatant fraction, and dilute to 2 000 ml in a volumetric flask. Transfer this solution into a polyeth
47、ylene bottle using a 25 ml automatic filling burette with soda-lime tubes to absorb the carbon dioxide in the air. Pipette precisely 100 ml of boron(III) oxide standard solution (0,1 mg/ml) into a 200 ml beaker and stir by using a magnetic stirrer, put a pH electrode into the solution and add drops
48、of the sodium hydroxide standard volumetric solution until the pH is 6,5. Remove the electrode, add 10 g of D()-mannitol, set the electrode again, and titrate with the sodium hydroxide standard volumetric solution until the pH is 6,8. Calculate the equivalent factor, F, the mass in g, of boron(III)
49、oxide equivalent to 1 ml of sodium hydroxide standard volumetric solution, using Equation (1). 0,01FV= (1) where V is the volume, in ml, of titration of sodium hydroxide standard volumetric solution after addition of D()-mannitol. BS EN ISO 21078-1:20084 6.3 Apparatus Ordinary laboratory apparatus and the following. 6.3.1 Vitreous carbon dishes, of suitable nominal capacity. 6.3.2 Vitreous carbon lids, to fit 6.3.1. 6.3.3 Muffle furnace, capable of being controlled at temperatures up to at least 700 C. 6.3.4 pH meter, with a g
