EN 15916-2-2010 en Copper and copper alloys - Determination of tellurium content - Part 2 Medium tellurium content - Flame atomic absorption spectrometric method (FAAS)《铜及铜合金 碲含量的测.pdf

1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 15916-2:2010Copper and copper alloys Determination of telluriumcontentPart 2: Medium tellurium content Flameatomic absorption spectrometric method(FAAS)BS EN 15916-2:2010 B

2、RITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 15916-2:2010.The UK participation in its preparation was entrusted to TechnicalCommittee NFE/34, Copper and copper alloys.A list of organizations represented on this committee can beobtained on request to its secret

3、ary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 66411 3ICS 77.040.30; 77.120.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard wa

4、s published under the authority of theStandards Policy and Strategy Committee on 31 August 2010Amendments issued since publicationDate Text affectedBS EN 15916-2:2010EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15916-2 July 2010 ICS 77.040.30; 77.120.30 English Version Copper and copper allo

5、ys - Determination of tellurium content - Part 2: Medium tellurium content - Flame atomic absorption spectrometric method (FAAS) Cuivre et alliages de cuivre - Dtermination du tellure - Partie 2: Tellure en moyenne teneur - Mthode par spectromtrie dabsorption atomique dans la flamme (SAAF) Kupfer un

6、d Kupferlegierungen - Bestimmung von Tellurgehalten - Teil 2: Mittlerer Tellurgehalt - Flammenatomabsorptionsspektrometrisches Verfahren (FAAS) This European Standard was approved by CEN on 19 June 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the co

7、nditions 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 application to the CEN Management Centre or to any CEN member. This European Standard exists in t

8、hree 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 CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies o

9、f Austria, Belgium, Bulgaria, Croatia, 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

10、. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15916-2:2010: EBS EN 1

11、5916-2:2010EN 15916-2:2010 (E) 2 Contents Page Foreword 31 Scope 42 Normative references 43 Principle 44 Reagents .45 Apparatus .56 Sampling .57 Procedure .57.1 Preparation of the test portion solution 57.2 Blank test 57.3 Check test .57.4 Establishment of the calibration curve .67.5 Determination .

12、78 Expression of results 78.1 Use of calibration curve 78.2 Use of bracketing method .89 Precision .810 Test report 9Bibliography . 10BS EN 15916-2:2010EN 15916-2:2010 (E) 3 Foreword This document (EN 15916-2:2010) has been prepared by Technical Committee CEN/TC 133 “Copper and copper alloys”, the s

13、ecretariat of which is held by DIN. 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 January 2011, and conflicting national standards shall be withdrawn at the latest by January 2011. Attention is

14、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. Within its programme of work, Technical Committee CEN/TC 133 requested CEN/TC 133/WG 10 “Methods of

15、 analysis“ to prepare the following document: EN 15916-2, Copper and copper alloys Determination of tellurium content Part 2: Medium tellurium content Flame atomic absorption spectrometric method (FAAS). This is one of two parts of the standard for the determination of tellurium content in copper an

16、d copper alloys. The other standard is: FprCEN/TS 15916-1, Copper and copper alloys Determination of tellurium content Part 1: Low tellurium content Flame atomic absorption spectrometric method (FAAS). According to the CEN/CENELEC Internal Regulations, the national standards organizations of the fol

17、lowing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slo

18、vakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 15916-2:2010EN 15916-2:2010 (E) 4 1 Scope This European Standard specifies a flame atomic absorption spectrometric method (FAAS) for the determination of the tellurium content of copper and copper alloys in form of castings or

19、 unwrought or wrought products. The method is applicable to products having tellurium mass fractions between 0,20 % and 1,00 %. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For

20、undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1811-1, Copper and copper alloys Selection and preparation of samples for chemical analysis Part 1: Sampling of cast unwrought products ISO 1811-2, Copper and copper alloys Selection and prepara

21、tion of samples for chemical analysis Part 2: Sampling of wrought products and castings 3 Principle Dissolution of a test portion in nitric acid followed, after suitable dilution, by aspiration into an air/acetylene flame of an atomic absorption spectrometer. Measurement of the absorption of the 214

22、,3 nm line emitted by a tellurium hollow-cathode lamp. 4 Reagents During the analysis, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 4.1 Nitric acid, HNO3( = 1,40 g/ml). 4.2 Hydrochloric acid, HCl ( = 1,19 g/ml). 4.3 Nitric acid solution, 2

23、+ 1. Add 200 ml of nitric acid (4.1) to 100 ml of water. 4.4 Hydrochloric acid solution, HCl (2 mol/l). In a 1 000 ml one-mark volumetric flask containing about 500 ml of water, add 165 ml of hydrochloric acid (4.2). Dilute to the mark with water and mix well. 4.5 Tellurium stock solution, 1 g/l Te.

24、 Weigh (0,5 0,001) g of tellurium (Te 99,9 %) and transfer it into a 250 ml beaker. Add 10 ml of nitric acid solution (4.3) and dissolve on a water bath. Evaporate to a wet residue, and then dissolve in 10 ml of hydrochloric acid solution (4.4). Transfer to a 500 ml one-mark volumetric flask, dilute

25、 to the mark with hydrochloric acid solution (4.4) and mix well. 1 ml of this solution contains 1,0 mg of Te. BS EN 15916-2:2010EN 15916-2:2010 (E) 5 4.6 Copper base solution, 10 g/l Cu. Weigh 10,0 g of pure electrolytic copper (Cu 99,95 %) and transfer it into a 600 ml beaker. Add 200 ml of nitric

26、acid (4.1). Heat gently until copper is dissolved, then heat until all nitrous fumes are expelled. Dilute with hydrochloric acid (4.2). Cool to room temperature. Transfer the solution quantitatively into a 1 000 ml one-mark volumetric flask, dilute to the mark with hydrochloric acid (4.2) and mix we

27、ll. 5 Apparatus 5.1 Atomic absorption spectrometer, fitted with an air/acetylene burner. 5.2 Tellurium hollow-cathode lamp. 6 Sampling Sampling shall be carried out in accordance with ISO 1811-1 or ISO 1811-2, as appropriate. Test samples shall be in the form of fine drillings, chips or millings wit

28、h a maximum thickness of 0,5 mm. 7 Procedure 7.1 Preparation of the test portion solution 7.1.1 Test portion Weigh (0,5 0,001) g of the test sample. 7.1.2 Test portion solution Transfer the test portion (7.1.1) into a 250 ml beaker. Add 10 ml of nitric acid (4.1). Cover with a watch glass and heat g

29、ently until the test portion is completely dissolved and then heat until all nitrous fumes have been expelled. Add 40 ml of hydrochloric acid (4.2) and transfer the test solution quantitatively into a 100 ml one-mark volumetric flask. Dilute to the mark with water and mix well. 7.2 Blank test Carry

30、out a blank test simultaneously with the determination, following the same procedure and using the same quantities of all reagents as used for the determination, but omitting the test portion. 7.3 Check test Make a preliminary check of the apparatus by preparing a solution of a reference material or

31、 a synthetic sample containing a known amount of tellurium and of composition similar to the material to be analysed. Carry out the procedure specified in 7.5. BS EN 15916-2:2010EN 15916-2:2010 (E) 6 7.4 Establishment of the calibration curve 7.4.1 Preparation of calibration solutions 7.4.1.1 Genera

32、l In all cases, copper, chloride and nitrate concentrations, and acidity in the calibration solutions shall be similar to those of the test portion solutions. The presence of copper in the calibration solutions compensates for chemical interaction effects of copper in the test solution. Normally no

33、similar additions are required to compensate for the effect of alloying elements. If an alloying element is present in the material to be analysed in mass fraction 10 %, an appropriate mass of this element shall be added to the calibration solutions. The volumes of copper base solution added (4.6) h

34、ave been calculated to compensate for chemical interaction effects of copper in test solutions of copper or high-copper alloys. Overcompensation may occur if the same volumes are added when the test samples are copper-based alloys where the percentage of copper is lower. In these cases the volumes o

35、f copper base solution shall be decreased to match the copper content of the test sample in solution. The tellurium concentration of the calibration solutions shall be adjusted to suit the sensitivity of the spectrometer used, so that the curve of absorbance as a function of concentration is a strai

36、ght line. 7.4.1.2 Tellurium mass fraction between 0,20 % and 1,0 % Into each of a series of six 100 ml one-mark volumetric flasks, introduce the volumes of tellurium stock solution (4.5) and copper base solution (4.6) shown in Table 1. Dilute to the mark with water and mix well. Table 1 Calibration

37、for tellurium mass fractions between 0,20 % and 1,0 % Tellurium standard solution volume (4.5) Corresponding tellurium mass Corresponding tellurium concentration after final dilution Copper base solution volume (4.6) Corresponding copper mass Corresponding tellurium mass fraction of sample ml mg g/m

38、l ml g % 0a0 0 50 0,5 0 1 1,0 10 50 0,5 0,2 2 2,0 20 50 0,5 0,4 3 3,0 30 50 0,5 0,6 4 4,0 40 50 0,5 0,8 5 5,0 50 50 0,5 1,0 aBlank test on reagents for calibration curve. 7.4.2 Adjustment of the atomic absorption spectrometer Fit the tellurium hollow-cathode lamp (5.2) into the atomic absorption spe

39、ctrometer (5.1), switch on the current and allow it to stabilize. Adjust the wavelength in the region of 214,3 nm to minimum absorbance. Following the manufacturers instructions, fit the correct burner, light the flame and allow the burner temperature to stabilize. The flame shall be set up on oxidi

40、sing conditions. Taking careful note of the manufacturers instructions regarding the minimum flow rate of acetylene, aspirate the calibration solution of highest concentration of analyte and adjust the burner configuration and gas flows to obtain maximum absorbance. BS EN 15916-2:2010EN 15916-2:2010

41、 (E) 7 7.4.3 Spectrometric measurement Aspirate the series of calibration solutions (7.4.1.2) in succession into the flame and measure the absorbance for each solution. Take care to keep the aspiration rate constant throughout the preparation of the calibration curve. Spray water through the burner

42、after each measurement. NOTE For certain types of apparatus, instead of water it is preferable to use a solution containing the attack reagents, in the same concentrations as in the test portion solutions. 7.4.4 Calibration curve Establish the calibration curve using measured absorbances and corresp

43、onding analyte amounts. Use appropriate spectrometer software or an off-line computer for regression calculations or prepare a graphical representation. 7.5 Determination 7.5.1 General The analyses shall be carried out independently, in duplicate. 7.5.2 Preliminary spectrometric measurement Carry ou

44、t a preliminary measurement on the test portion solution (7.1.2) following the procedure specified in 7.4.3 at the same time as the spectrometric measurements are carried out on the standard calibration solutions (7.4.1). Estimate the preliminary analyte amount by using the calibration curve accordi

45、ng to 7.4.4. NOTE In presence of silver a precipitate of AgCl will occur. Filter before any spectrometric measurement. 7.5.3 Spectrometric measurements 7.5.3.1 Use of the calibration curve Repeat the measurements and calculate the concentration directly using the calibration curve. 7.5.3.2 Use of br

46、acketing method Carry out a second measurement on the test portion solution (7.1.2) following the procedure specified in 7.4.3, by bracketing between two calibration solutions of composition similar to that of the calibration solutions (7.4.1), but having tellurium concentrations slightly higher and

47、 slightly lower ( 10 %) than the estimated tellurium concentration of the test portion solution. To prepare these calibration solutions, follow the procedure specified in 7.4.1 using, however, suitable quantities of tellurium stock solution (4.5). 8 Expression of results 8.1 Use of calibration curve

48、 Calculate the tellurium mass fraction, in percent (%), as follows: 100f1Te= Vmcw (1) where BS EN 15916-2:2010EN 15916-2:2010 (E) 8 wTe is the tellurium mass fraction in percent (%); c1is the tellurium concentration from the calibration curve, in micrograms per millilitre (g/ml) to be converted in m

49、illigrams per millilitre (mg/ml); m is the mass of the test portion, in milligrams (mg); Vfis the total volume of the test portion solution (7.1.2), in millilitres (ml). 8.2 Use of bracketing method Calculate the tellurium mass fraction, in percent (%), as follows: 100f2Te= Vmcw (2) where c2is the tellurium concentration, calculated using Equation (3), in micrograms per millilitre (g/ml) to be converted in milligrams per millilitre (mg/ml); m is the mass of the test