1、BRITISH STANDARD BS 6200-3.18.3: 1985 EN 24159:1989 ISO 4159:1978 Incorporating Amendment No.1 Sampling and analysis of iron, steel and other ferrous metals Part 3: Methods of analysis Section 3.18 Determination of manganese Subsection 3.18.3 Ferromanganese and ferrosilicomanganese: potentiometric m
2、ethod The European Standard EN24159:1989 has the status of a British Standard UDC 669.15-198:543.257.1:546.711BS6200-3.18.3:1985 This British Standard, having been prepared under the directionof the Iron and Steel Standards Committee, was published under the authority ofthe Board of BSI and comes in
3、toeffect on 28 February 1985 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference ISM/18 Draft for comment 77/79237 DC ISBN 0 580 14267 1 National foreword This Subsection of BS 6200 has been prepared under the direction of the Iron and Steel Standards Co
4、mmittee. It is identical with ISO 4159:1978 “Ferromanganese and ferrosilicomanganese Determination of manganese content Potentiometric method” published by the International Organization for Standardization (ISO) and supersedes method 3 for the determination of manganese in BSI Handbook No.19. In198
5、9 the European Committee for Standardization (CEN) accepted ISO4159:1978 as European Standard EN24159:1989. Terminology and conventions. The text of the International Standard has been approved as suitable for publication as a British Standard without deviation. Some terminology and certain conventi
6、ons are not identical with those used in British Standards; attention is drawn especially to the following. The comma has been used as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Wherever the words “International Standard”
7、appear, referring to this standard, they should be read as “British Standard”. Cross-reference. At present there is no corresponding British Standard for ISO3713 which is still at draft stage. Appropriate procedures from ISO3713 will be incorporated in BS6200-2 “Methods of sampling and sample prepar
8、ation” which will be published in due course. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligati
9、ons. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amend
10、ment table on the inside front cover. Amendments issued since publication Amd. No. Date of issue Comments 7073 February 1992 Indicated by a sideline in the marginBS6200-3.18.3:1985 BSI 09-1999 i Contents Page National foreword Inside front cover Brief history 2 Text of EN24159 3 Publication referred
11、 to Inside back coverii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 24159 May 1989 UDC 669.15-198:543.257.1:546.711 Descriptors: Iron and steel products, ferroalloys, ferromanganese, ferrosilicon, silico-manganese, chemical analysis, determination of content, manganese, potentiometric
12、method English version Ferromanganese and ferrosilicomanganese Determination of manganese content Potentiometric method (ISO 4159, 1st edition, 1978-12-15) Ferromanganse et ferro-silico-manganse Dosage du manganse Mthode potentiomtrique (ISO 4159,1re dition,1978-12-15) Bestimmung des Mangangehalt vo
13、n Ferromangan und Ferrosilicomangan Potentiometrisches Verfahren (ISO 4159,1. Ausgabe,1978-12-15) This European Standard was approved by CEN on1989-05-15. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the st
14、atus 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
15、 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 member are the national standards organizations of Austria, Belgium, Denmark, Finland, France, G
16、ermany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels CEN 198
17、9 Copyright reserved to all CEN members Ref. No. EN 24159:1989 EEN24159:1989 BSI 09-1999 2 Brief history On the proposal of the Technical Committee ECISS/TC20 “Methods of chemical analysis” the Coordinating Commission (COCOR) of the European Committee for Iron and Steel Standardization (ECISS) decid
18、ed on1987-11-24/25 to submit the International Standard ISO4159:1978, Ferromanganese and ferrosilicomanganese Determination of manganese content Potentiometric method (ISO4159,1st edition,1978-12-15) to the Formal Vote. This European Standard was adopted by CEN on1988-11-26. According to the Common
19、CEN/CENELEC Rules, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Statement The text of the Internat
20、ional Standard ISO4159, edition1,1978-12-15 was approved by CEN as a European Standard without any modification. Contents Page Brief history 2 1 Scope and field of application 3 2 Reference 3 3 Principle 3 4 Reagents 3 5 Apparatus 4 6 Sample 4 7 Procedure 4 8 Expression of results 5 9 Reproducibilit
21、y 5 10 Test report 5EN24159:1989 BSI 09-1999 3 1 Scope and field of application This International Standard specifies a potentiometric method for the determination of the manganese content of ferromanganese and ferrosilicomanganese. The method is applicable to alloys containing from55 to95%(m/m) of
22、manganese. 2 Reference ISO 3713, Ferroalloys Sampling and preparation of samples General rules 1) . 3 Principle Dissolution of a test portion with hydrochloric, hydrofluoric and perchloric acids. Potentiometric determination (see note) of manganese with potassium permanganate in a pyrophosphoric med
23、ium at a controlled pH, according to the reaction: 4 Mn 2+ MnO 4 + 8 H + 15 (P 2 O 7 H 2 ) 2 F 5 Mn(P 2 O 7 H 2 ) 3 3+ 4 H 2 O NOTEThe method may be completed by any other electrometric method: amperometric titration, dead-stop, etc. 4 Reagents During the analysis, use only reagents of recognized an
24、alytical grade, and only distilled water or water of equivalent purity, except where otherwise specified. 4.1 Perchloric acid 2) , 1,61g/ml. 4.2 Hydrofluoric acid, 1,14g/ml. 4.3 Hydrochloric acid, 1,19g/ml. 4.4 Hydrochloric acid, 1,19g/ml, diluted1+2. 4.5 Hydrochloric acid, 1,19g/ml, diluted1+4. 4.6
25、 Sodium pyrophosphate, saturated solution. Dissolve145g of sodium pyrophosphate (P 2 O 7 Na 4 .10H 2 O) in a2 litre conical flask, with about1litre of hot water; heat without exceeding, even locally, the temperature of60 C, until the salt is completely dissolved. Cool. Prepare this solution at the t
26、ime of use. 4.7 Potassium permanganate, recrystallized. Place50g of pure analytical grade potassium permanganate in the conical flask(5.1), and dissolve it in200ml of warm distilled water(70to80 C). Fit the reflux condenser(5.2) to the flask and boil the solution for20min. Filter the warm solution q
27、uickly under vacuum through a sintered glass funnel(5.3). Cool the filtrate in iced water, stirring vigorously, and allow the fine, crystalline precipitate to settle for10min. Decant the solution; then, using a glass spatula, transfer the crystalline mass into a funnel with a filter plate, porosity4
28、, and place under suction for a few minutes to remove most of the mother liquor. Dissolve the crystalline mass in160ml of distilled water (deionized water is not permitted for this phase), and repeat the recrystallization. After filtering and placing under suction for approximately5min, transfer the
29、 crystalline mass onto a150mm diameter watch glass using a glass spatula, and dry it in air, protected from light and dust. When the crystalline mass no longer agglomerates when crushed with the spatula, dry it at110 C for2h, then transfer it to a weighing bottle fitted with a ground glass-stopper.
30、Store in the dark. This salt contains34,76%(m/m) ofMn. 4.8 Potassium permanganate, about0,1N standard volumetric solution. 4.8.1 Preparation Dissolve3,20g of potassium permanganate in1000ml of water, Allow to stand for6days. Filter through glass wool or a sintered glass filter, then transfer to a br
31、own glass bottle. Mix. 4.8.2 Standardization Place about2,5g of the recrystallized potassium permanganate(4.7), weighed to the nearest0,0002g, in a250ml conical flask, and follow exactly the procedure specified in7.3. It is recommended that this standardization be carried out in parallel with the de
32、termination. The manganese equivalent T of the potassium permanganate solution(4.8), expressed in grams of manganese corresponding to1ml of solution, is given by the formula where 1) At present at the stage of draft. 2) Attention is drawn to the hazards associated with perchloric acid when heated to
33、 fuming. m 1 is the mass, in grams, of the crystallized potassium permanganate(4.7) used; V 0 is the volume, in millilitres, of the potassium permanganate solution(4.8) used for the blank test;EN24159:1989 4 BSI 09-1999 5 Apparatus Usual laboratory equipment, and in particular: 5.1 Erlenmeyer conica
34、l flask with ground neck 5.2 Reflux condenser with ground glass joint, to fit the flask(5.1). 5.3 Filter crucibles (porosity4) or filter funnels, capacity40ml. 5.4 Volumetric flask, capacity250ml. 5.5 Beaker, capacity600ml. 5.6 Conical flask, capacity250ml. 5.7 Dish, capacity250ml, or beaker, capaci
35、ty400ml, of polytetrafluoroethylene. 5.8 Magnetic stirrer 5.9 pH meter, fitted with glass and calomel electrodes. 5.10 Potentiometer, fitted with platinum and calomel electrodes. 6 Sample Use powder which will pass through a sieve with a mesh size of1604m, prepared in accordance with ISO3713. 7 Proc
36、edure 7.1 Test portion Take a test portion of1 0,0002g. 7.2 Blank test Carry out a blank test in parallel with the determination, following the same procedure and using the same reagents. 7.3 Determination 7.3.1 Attack the test portion as specified in7.3.1.1 or7.3.1.2, as appropriate. 7.3.1.1 Ferrom
37、anganese Transfer the test portion(7.1) to the conical flask(5.6) and attack it with20ml of the hydrochloric acid(4.3) and0,2ml of the hydrofluoric acid(4.2), then add10ml of the perchloric acid(4.1). 3) Proceed as specified in7.3.2. 7.3.1.2 Ferrosilicomanganese Transfer the test portion(7.1) to a d
38、ish or beaker(5.7). Attack it with10ml of the hydrochloric acid(4.3), add10ml of the perchloric acid(4.1) then, slowly, about20ml of the hydrofluoric acid(4.2). 3) Proceed as specified in7.3.2. 7.3.2 Heat gently at first, then progressively increase the heat until the formation of heavy perchloric f
39、umes. Continue heating until a syrupy consistency is obtained and manganese dioxide begins to precipitate. Allow to cool. 7.3.3 Take up with20ml of the hydrochloric acid solution(4.5). Heat gently until the solution clears. Rinse the sides of the vessel carefully with a jet from a washbottle and con
40、tinue heating for a few minutes. Add100ml of hot water, and cool to room temperature. Transfer, without filtering, to the volumetric flask(5.4). Rinse the vessel used for the attack carefully, cool and make up to the mark. Shake to mix the solution. 7.3.4 By means of a pipette, transfer50ml of the s
41、olution to the beaker(5.5). Dilute to100ml with water. Add250ml of the sodium pyrophosphate solution(4.6). Place the beaker on the magnetic stirrer(5.8) and add a magnetized bar. 7.3.5 Adjust the pH of the solution to a value between6,5 and7, using the pH meter(5.9), by adding the hydrochloric acid
42、solution(4.4). NOTEIn the case of ferromanganese containing chromium, it is necessary to wait for30min after the adjustment of the pH of the solution before carrying out the titration. Titrate with the potassium permanganate solution(4.8), adding it slowly to the beaker. Follow the indications of th
43、e potentiometer: the end of the titration is obtained when a sudden increase in potential of at least100mV is observed. It is recommended that a second titration be carried out under the same conditions on another aliquot portion of the test solution. V 1 is the volume, in millilitres, of the potass
44、ium permanganate solution(4.8) used for the standardization. 3) Oxidize the solution with nitric acid prior to adding the perchloric acid.EN24159:1989 BSI 09-1999 5 8 Expression of results The manganese content, expressed as a percentage by mass of the sample, is given by the formula where 9 Reprodu
45、cibility Experience has shown that the95%confidence limits for an experienced operator are 0,20%. 10 Test report The test report shall include the following particulars: a) the reference of the method used; b) the results and the method of expression used; c) any unusual features noted during the de
46、termination; d) any operation not included in this International Standard or regarded as optional. m 0 is the mass, in grams, of the test portion(7.1); V 0 is the volume, in millilitres, of the potassium permanganate solution(4.8) used for the blank test; V 2 is the volume, in millilitres, of the po
47、tassium permanganate solution(4.8) used for the determination(7.3.5); T is the manganese equivalent of the potassium permanganate solution(4.8), expressed in grams of manganese corresponding to1ml of the solution.6 blankBS6200-3.18.3:1985 BSI 09-1999 Publication referred to See national foreword.BS
48、6200-3.18.3: 1985 EN24159:1989 ISO4159:1978 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Ro
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