CEN TS 15916-1-2011 Copper and copper alloys - Determination of tellurium content - Part 1 Low tellurium content - Flame atomic absorption spectrometric method (FAAS)《铜及铜合金 碲含量的测定 .pdf

1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationDD CEN/TS 15916-1:2011Copper and copper alloys Determination of telluriumcontentPart 1: Low tellurium content Flameatomic absorption spectrometric method(FAAS)DD CEN/TS 15916-1:2

2、011 DRAFT FOR DEVELOPMENTNational forewordThis Draft for Development is the UK implementation of CEN/TS15916-1:2011.This publication is not to be regarded as a British Standard.It is being issued in the Draft for Development series of publicationsand is of a provisional nature. It should be applied

3、on thisprovisional basis, so that information and experience of its practicalapplication can be obtained.Comments arising from the use of this Draft for Developmentare requested so that UK experience can be reported to theinternational organization responsible for its conversion toan international s

4、tandard. A review of this publication willbe initiated not later than 3 years after its publication by theinternational organization so that a decision can be taken on itsstatus. Notification of the start of the review period will be made inan announcement in the appropriate issue of Update Standard

5、s.According to the replies received by the end of the review period,the responsible BSI Committee will decide whether to support theconversion into an international Standard, to extend the life of theTechnical Specification or to withdraw it. Comments should be sentto the Secretary of the responsibl

6、e BSI Technical Committee at BritishStandards House, 389 Chiswick High Road, London W4 4AL.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 secretary.Thi

7、s publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 71095 7ICS 77.120.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This Draft for Development was published u

8、nder the authority ofthe Standards Policy and Strategy Committee on 28 February 2011.Amendments issued since publicationDate Text affectedDD CEN/TS 15916-1:2011TECHNICAL SPECIFICATION SPCIFICATION TECHNIQUE TECHNISCHE SPEZIFIKATION CEN/TS 15916-1 February 2011 ICS 77.120.30 English Version Copper an

9、d copper alloys - Determination of tellurium content - Part 1: Low tellurium content - Flame atomic absorption spectrometric method (FAAS) Cuivre et alliages de cuivre - Dtermination du tellure - Partie 1: Tellure en faible teneur - Mthode par spectromtrie dabsorption atomique dans la flamme (SAAF)

10、Kupfer und Kupferlegierungen - Bestimmung des Tellurgehaltes - Teil 1: Niedriger Tellurgehalt - Flammenatomabsorptionsspektrometrisches Verfahren (FAAS) This Technical Specification (CEN/TS) was approved by CEN on 11 October 2010 for provisional application. The period of validity of this CEN/TS is

11、limited initially to three years. After two years the members of CEN will be requested to submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard. CEN members are required to announce the existence of this CEN/TS in the same way as for an EN a

12、nd to make the CEN/TS available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached. CEN members are the national st

13、andards bodies of 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 an

14、d United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TS 15

15、916-1:2011: EDD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 2 Contents Page Foreword 31 Scope 42 Normative references 43 Principle 44 Reagents .45 Apparatus .56 Sampling .57 Procedure .58 Expression of results 89 Precision .910 Test report 9Bibliography . 10DD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (

16、E) 3 Foreword This document (CEN/TS 15916-1:2011) has been prepared by Technical Committee CEN/TC 133 “Copper and copper alloys”, the secretariat of which is held by DIN. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or

17、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 analysis“ to prepare the following Technical Specification: CEN/TS 15916-1, Copper and copper alloys Determination

18、of tellurium content Part 1: Low tellurium content Flame atomic absorption spectrometric method (FAAS) This is one of two parts of the Technical Specification/European Standard for the determination of tellurium content in copper and copper alloys. The other part is: EN 15916-2, Copper and copper al

19、loys Determination of tellurium content Part 2: Medium tellurium content Flame atomic absorption spectrometric method (FAAS) According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to announce this Technical Specification: Austria,

20、 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 the United Kingdom. DD C

21、EN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 4 1 Scope This Technical Specification 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 unwrought or wrought products. The method is applicable t

22、o products having tellurium mass fractions between 0,000 2 % and 0,020 %. 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 referenc

23、ed 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 preparation of samples for chemical analysis Part 2: Sampling

24、 of wrought products and castings 3 Principle Dissolution of a test portion in hydrochloric acid and hydrogen peroxide. Precipitation of tellurium by hypophosphorous acid in the presence of arsenic. After filtration, dissolution of the precipitate with hydrochloric acid - hydrogen peroxide mixture f

25、ollowed, after suitable dilution, by aspiration of the test solution into an air/acetylene flame of an atomic absorption spectrometer. Measurement of the absorption of the 214,3 nm line emitted by a tellurium hollow-cathode lamp. 4 Reagents Use only reagents of recognized analytical grade and only d

26、istilled water or water of equivalent purity. 4.1 Hydrochloric acid, HCl ( = 1,19 g/ml) 4.2 Nitric acid, HNO3( = 1,40 g/ml) 4.3 Hypophosphorous acid, H3PO2( = 1,25 g/ml) 4.4 Hydrochloric acid solution, 1 + 1 Add 500 ml of hydrochloric acid (4.1) to 500 ml of water. 4.5 Hydrogen peroxide, H2O2, 30 %

27、solution ( = 1,11 g/ml)4.6 Arsenic(III) oxide, 4,0 g/l solution Dissolve 4,0 g of arsenic(III) oxide (As2O3) in 100 ml of water with the addition of 10 ml of hydrochloric acid solution (4.4), heat gently. Dilute with water to 1 000 ml and mix. 4.7 Arsenic(III) oxide, 0,8 g/l solution Dilute 100 ml o

28、f arsenic(III) oxide solution (4.6) in water to 500 ml. DD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 5 4.8 Tellurium stock solution, 0,1 g/l Te Weigh (0,1 0,001) g of tellurium (Te 99,9 %) and transfer it into a 250 ml beaker. Add 20 ml of nitric acid (4.2) and dissolve on a steam bath. Transfer to

29、 a 1 000 ml one-mark volumetric flask. Dilute to the mark with water and mix. Prepare this solution immediately prior to use. 1 ml of this solution contains 100 g of Te. 4.9 Tellurium standard solution, 0,025 g/l Te Transfer 25,0 ml of the tellurium stock solution (4.8) to a 100 ml one-mark volumetr

30、ic flask. Dilute to the mark with water and mix. Prepare this solution immediately prior to use. 1 ml of this solution contains 25 g of Te. 4.10 Hydrochloric acid - hydrogen peroxide mixture Mix 10 ml of hydrochloric acid (4.1) and 5 ml of hydrogen peroxide (4.5). Prepare this solution immediately p

31、rior to use. 5 Apparatus 5.1 Membrane filter, cellulose nitrate, 25 mm to 30 mm diameter, pore size 0,45 m to 0,8 m, fitted on appropriate filtration apparatus 5.2 Atomic absorption spectrometer, fitted with an air/acetylene burner 5.3 Tellurium hollow-cathode lamp 6 Sampling Sampling shall be carri

32、ed 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 with a maximum thickness of 0,5 mm. 7 Procedure 7.1 Preparation of the test portion solution 7.1.1 Test portion Weigh (10 0,001) g of the test sample. 7.1.2 Test

33、 portion solution Transfer the test portion (7.1.1) into a 750 ml conical flask. Add 180 ml of hydrochloric acid (4.1) and 30 ml of water. With constant cooling and swirling, complete the dissolution by adding small portions of hydrogen peroxide (4.5). Boil the solution for approximately 5 min to de

34、stroy excess hydrogen peroxide, and then allow DD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 6 to cool. This operation shall be performed carefully, since the presence of hydrogen peroxide in the test solution will result in a violent reaction when the hypophosphorous acid is added. Add 5 ml of arse

35、nic(III) oxide solution (4.7) and 30 ml of hypophosphorous acid (4.3) to the cooled solution, then boil for 5 min. Allow the precipitate to settle for 30 min before filtering through a membrane filter (5.1). Wash the filter 5 times with small amounts of hydrochloric acid solution (4.4). Transfer the

36、 membrane filter and any accessories into a 100 ml beaker. Add 5 ml of warm hydrochloric acid - hydrogen peroxide mixture (4.10). Remove the filter and any accessories and wash them with water. Gently evaporate to a small volume (about 3 ml). 7.1.3 Tellurium mass fraction between 0,000 2 % and 0,001

37、 % Transfer the solution (7.1.2) to a 5 ml one-mark volumetric flask, wash the beaker sides, dilute to the mark with water and mix. Proceed as indicated in 7.5. 7.1.4 Tellurium mass fraction between 0,001 % and 0,005 % Transfer the solution (7.1.2) to a 25 ml one-mark volumetric flask. Add 13,5 ml o

38、f hydrochloric acid (4.1) and 4 ml of arsenic(III) oxide solution (4.6). Dilute to the mark with water and mix. Proceed as indicated in 7.5. 7.1.5 Tellurium mass fraction between 0,005 % and 0,02 % Transfer the solution (7.1.2) to a 100 one-mark volumetric flask. Add 64 ml of hydrochloric acid (4.1)

39、 and 19 ml of arsenic(III) oxide (4.6). Dilute to the mark with water and mix. Proceed as indicated in 7.5. 7.2 Blank test Carry 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 subst

40、ituting pure copper for the test portion. 7.3 Check test Make a preliminary check of the apparatus by preparing a solution of a reference material or a synthetic sample containing a known amount of tellurium and of composition similar to the material to be analysed. Carry out the procedure specified

41、 in 7.5. 7.4 Establishment of the calibration curve 7.4.1 Preparation of calibration solutions Into each of a series of eight 50 ml one-mark volumetric flasks, introduce 33,5 ml of hydrochloric acid (4.1) and 10,0 ml of arsenic(III) oxide solution (4.6). Add, the volumes of tellurium stock solution

42、(4.8) or tellurium standard solution (4.9) shown in Table 1. Dilute to the mark with water and mix. DD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 7 Table 1 Calibration for tellurium mass fractions between 0,000 2 % and 0,020 % Tellurium standard solution volume (4.9) Tellurium stock solution volume

43、(4.8) Corresponding tellurium mass Corresponding tellurium concentrationafter final dilution ml ml mg g/ml 0 a 0 0 2 0,05 1,0 4 0,10 2,0 10 0,25 5,0 5,0 0,50 10,0 7,5 0,75 15,0 10,0 1,00 20,0 12,5 1,25 25,0aBlank test on reagents for calibration curve. 7.4.2 Adjustment of the atomic absorption spect

44、rometer Fit the tellurium hollow-cathode lamp (5.3) into the atomic absorption spectrometer (5.2), switch on the current and allow it to stabilize. Adjust the wavelength in the region of 214,3 nm to minimum absorbance. Following manufacturers instructions, fit the correct burner, light the flame and

45、 allow the burner temperature to stabilize. The flame shall be set-up on oxidising 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

46、 and gas flows to obtain maximum absorbance. 7.4.3 Spectrometric measurement Aspirate the series of calibration solutions (7.4.1) in succession into the flame and measure the absorbance for each solution. Take care to keep the of aspiration rate constant throughout the preparation of the calibration

47、 curve. Spray water through the burner after each measurement (see NOTE). NOTE For certain types of spectrometer, 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 cal

48、ibration curve using measured absorbances and corresponding 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.

49、 7.5.2 Preliminary spectrometric measurement Carry out a preliminary measurement on the test portion solution (7.1.3 or 7.1.4 or 7.1.5) 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 (7.4.4). DD CEN/TS 15916-1:2011CEN/TS 15916-1:2011 (E) 8 7.5.3 Spectrometric measurements 7.5.3.1 Use of the calib