BS PD ISO TR 16043-2015 Iron ores Determination of chlorine content X-ray fluorescence spectrometric method《铁矿石 氯含量的测定 X射线荧光光谱法》.pdf

1、BSI Standards Publication Iron ores Determination of chlorine content X-ray fluorescence spectrometric method PD ISO/TR 16043:2015National foreword This Published Document is the UK implementation of ISO/TR 16043:2015. The UK participation in its preparation was entrusted to Technical Committee ISE/

2、58, Iron ores. A list of organizations represented 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. The British Standards Institution 2015. Publis

3、hed by BSI Standards Limited 2015 ISBN 978 0 580 86762 0 ICS 73.060.10 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 November 2015. Amendments/corrigenda

4、 issued since publication Date Text affected PUBLISHED DOCUMENT PD ISO/TR 16043:2015 ISO 2015 Iron ores Determination of chlorine content X-ray fluorescence spectrometric method Minerais de fer Dosage du chlore Mthode par spectromtrie de fluorescence de rayons X TECHNICAL REPORT ISO/TR 16043 Referen

5、ce number ISO/TR 16043:2015(E) First edition 2015-10-15 PD ISO/TR 16043:2015 ISO/TR 16043:2015(E)ii ISO 2015 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized

6、otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright of

7、fice Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.org PD ISO/TR 16043:2015 ISO/TR 16043:2015(E)Foreword v Introduction vi 1 Scope . 1 2 Principle 1 3 Reagents and materials . 1 4 Apparatus . 2 5 Sampling and sampl

8、es 3 5.1 Laboratory sample . 3 5.2 Preparation of test sample 3 5.2.1 Preparation of pre-dried test samples 3 5.2.2 Ores having significant contents of combined water or oxidizable compounds 4 6 Procedure. 4 6.1 Preparation of discs 4 6.1.1 General 4 6.1.2 Weighing . 4 6.1.3 Mixing 5 6.1.4 Fusion 5

9、6.1.5 Casting 5 6.1.6 Calibration discs . 5 6.1.7 Test discs . 6 6.1.8 Visual inspection 6 6.1.9 Disc storage 6 6.1.10 Cleaning of platinum ware 6 6.2 Measurements . 7 6.2.1 General 7 6.2.2 Analytical lines. 7 6.2.3 XRF generator settings . 7 6.2.4 Crystals . 7 6.2.5 Counting times . 7 6.2.6 Collima

10、tors 8 6.2.7 Simultaneous-type instruments . 8 6.2.8 Sample holders 8 6.2.9 Subsequent determinations . 8 7 Calculation of results . 8 7.1 General . 8 7.2 Correction for background . 9 7.3 Calibration 9 8 General treatment of results .10 8.1 Acceptability of background equivalent concentration (BEC)

11、10 8.2 Repeatability and permissible tolerances 10 8.3 Determination of analytical result 11 8.3.1 Mean of duplicates 11 8.3.2 Between-laboratories precision 11 8.4 Check for trueness 11 8.5 Calculation of final result 12 8.6 Oxide factor .12 9 Test report 12 Annex A (informative) Preparation of flu

12、x A .13 Annex B (informative) Preparation of flux B .15 ISO 2015 All rights reserved iii Contents Page PD ISO/TR 16043:2015 ISO/TR 16043:2015(E)Annex C (informative) Flowsheet of the procedure for the acceptance of analytical values for test samples .16 Annex D (informative) Derivation of repeatabil

13、ity and permissible tolerance 17 Bibliography .18 iv ISO 2015 All rights reserved PD ISO/TR 16043:2015 ISO/TR 16043:2015(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Internationa

14、l 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 ISO,

15、also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part

16、1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the el

17、ements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations recei

18、ved (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs ad

19、herence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 102, Iron ore and direct reduced iron, Subcommittee SC 2, Chemical analysis. ISO 2015 All rights reserved v PD ISO/

20、TR 16043:2015 ISO/TR 16043:2015(E) Introduction This Technical Report summarizes the results of inter-laboratory testing for the determination of chlorine in iron ores by X-ray fluorescence. The method was developed by Technical Committee ISO/TC 102, Iron ore and direct reduced iron, Subcommittee SC

21、 2, Chemical analysis. As no other methods for determination of chlorine exist in ISO/TC 102, the method was designed to complement method ISO 9516-1. A method for water soluble chloride does exist (ISO 9517) but the range of application of ISO 9517 is significantly less than the XRF method describe

22、d in this Technical Report. The method described in this Technical Report represents the first attempt of the committee to determine total chloride. Evaluation of the data from the inter-laboratory test indicated that the method could not be considered for publication as an International Standard as

23、 the precision of the method was less good than the precision of the method for water soluble chloride described in ISO 9517. In addition, a test on the trueness of the method was not possible as no potential test samples that were certified for Cl were available. Although the test samples used were

24、 characterized using neutron activation, the XRF values were biased with respect to the neutron activation values and the neutron activation method itself was not considered to be a standard method. Although the method was not considered suitable for publication as an International Standard, it was

25、agreed that the method was otherwise suitable for use in the industry and the committee agreed that it should be published as a Technical Report.vi ISO 2015 All rights reserved PD ISO/TR 16043:2015 Iron ores Determination of chlorine content X-ray fluorescence spectrometric method WARNING This Techn

26、ical Report may involve hazardous materials, operations and equipment. This Technical Report does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this Technical Report to establish appropriate health and safety practices and determin

27、e the applicability of regulatory limitations prior to use. 1 Scope This Technical Report sets out a wavelength dispersive X-ray fluorescence procedure for the determination of chlorine in iron ores. The method is applicable to a concentration range of 0,027 % to 1,15 % of chlorine in iron ores rega

28、rdless of mineralogical type. It is not intended that this method be used for the purpose of trade in iron ores due to the precision of the method. 2 Principle The glass discs for X-ray fluorescence measurement are prepared by incorporating the test portion of the iron ore sample, via fusion, into a

29、 borate glass disc using a casting procedure. By using a fused glass disc, particle size effects are eliminated. The method is applicable to data from simultaneous and sequential X-ray fluorescence spectrometers. Calibration is carried out using pure chemicals, with chlorine added as a stock solutio

30、n of sodium chloride. Because the oxygen of the flux is the dominant element in the glass disc, and because oxygen is a heavy absorber to Cl K, matrix effects are small and calibration is based on a linear relationship between concentration and measured fluorescent intensity. Background measurements

31、 are made to determine net line intensities. 3 Reagents and materials 3.1 During analysis, use only reagents of recognized high purity. Where reagents have been ignited, they should be covered during cooling in the desiccator and weighed as soon as possible. 3.2 Iron (III) oxide (Fe 2 O 3 ), nominal

32、ly 99,999 % Fe 2 O 3 . The iron (III) oxide should contain less than 3 g/g of chlorine. It should initially be heated at 1 000 C in a platinum crucible for a minimum of 12 h to reduce contaminant concentrations and cooled in a desiccator. Subsequently, if required, it should be re-ignited at 1 000 C

33、 for 1 h and cooled in a desiccator. 3.3 Sodium chloride (NaCl), 13,2 g/l solution. Analytical grade sodium chloride should be dried at 105 C for 1 h and cooled in a desiccator. Weigh 13,2 g dried sodium chloride into a 1 000 ml one-mark volumetric flask and dilute to volume. 3.4 Desiccant, should b

34、e a freshly-regenerated self-indicating silica gel. TECHNICAL REPORT ISO/TR 16043:2015(E) ISO 2015 All rights reserved 1 PD ISO/TR 16043:2015 ISO/TR 16043:2015(E) 3.5 Flux. 3.5.1 General Flux A or flux B may be used. The levels of contamination in the flux should be checked (see 8.1). Because levels

35、 of contamination may vary from batch to batch, the same batch of flux should be used for all discs (iron ore, blank, and calibration) involved in the batch of determinations. 3.5.2 Flux A Flux A should be prepared by fusion of a mixture of anhydrous lithium tetraborate (Li 2 B 4 O 7 ) and anhydrous

36、 lithium metaborate (Li 2 BO 2 ) by the procedure specified in Annex A. Flux should be dried at 500 C for a minimum of 4 h and stored in a desiccator. 3.5.3 Flux B Flux B should be prepared using lithium tetraborate by the procedure specified in Annex B. Flux should be dried at 500 C for a minimum o

37、f 4 h and stored in a desiccator. 4 Apparatus 4.1 General A conventional electric furnace, high-frequency furnace, gas burner or a commercial disc-making machine may be used to fuse and cast the discs. 4.2 Balance, an analytical balance capable of weighing to four decimal places. 4.3 Crucible and mo

38、uld, made from a non-wetting platinum alloy. NOTE Either platinum/gold or platinum/gold/rhodium alloys are suitable. The sample may be fused with the flux in a crucible and then poured into a separate mould or, if an appropriately shaped crucible is used, the fusion may be carried out and the glass

39、is allowed to cool in the same crucible. Both methods will produce glass discs of the same quality. The crucible should have sufficient capacity to hold the flux and sample required for fusion. Where the crucible is to be used as a mould as well as for fusion, it should have a flat bottom of a diame

40、ter appropriate to the spectrometer. The inside of the crucible should be polished regularly with approximately 3 m diamond paste to ensure that the glass disc releases easily. To prevent deformation through repeated heating and cooling, the base should be thicker than 2 mm. Because the bottom of th

41、e disc is the analytical surface, the inside bottom surface of the mould should be flat and should be polished regularly with approximately 3 m diamond paste to ensure that the glass disc releases easily from the mould. To prevent deformation through repeated heating and cooling, the base should be

42、greater than 2 mm thick. 4.4 Electric furnace, capable of maintaining a temperature in the range of 1 000 C to 1 050 C. The furnace may be of a conventional type with heating elements or may be a high-frequency furnace. The temperature of the melt should be in the range 1 000 C to 1 050 C and is not

43、 to exceed 1 050C to minimize loss of chlorine by volatilization. The temperature should be checked using an optical pyrometer while the crucible contains several grams of flux. Alternatively, if an optical pyrometer is not available, heat about 10 g of potassium sulphate (mp 1 069C) in a crucible f

44、or 10 min. There should be no evidence that the salt has melted during heating, but it may be sintered. If the potassium sulphate has melted, then repeat at a lower fusion temperature. The furnace should be regularly cleaned to prevent contamination of the samples.2 ISO 2015 All rights reserved PD I

45、SO/TR 16043:2015 ISO/TR 16043:2015(E) 4.5 Gas-oxygen burner. Where fusions are made over a gas-oxygen flame, the flame should not be excessively oxygen-rich to minimize chlorine loss. As for the electric furnace, temperature is not to exceed 1 050C to minimize loss of chlorine by volatilization. The

46、 temperature is to be checked using an optical pyrometer or by heating potassium sulphate as described in 4.4. A gas burner may be used for heating the mould and it is to be adjusted so that the mould is a bright red (approximately 950 C). A Meker burner should not be used, as uptake of iron from th

47、e glass into the platinum ware may occur. 4.6 Desiccator. 4.7 Spatulas, non-magnetic, for weighing of the test portion and for mixing. Vibrating spatulas are not acceptable because they can lead to segregation of the sample. 4.8 X-ray fluorescence spectrometer, any wavelength dispersive, vacuum (or

48、helium) path, X-ray fluorescence spectrometer, provided that the instrument has been checked. Performance checks should be carried out in accordance with the precision tests set out in AS 2563, accumulating at least 10 5counts for each measurement. 4.9 Ultrasonic bath. This item is optional. It may

49、be used to aid cleaning of the platinum ware. 4.10 Cooling device. It is recommended that the mould and glass be cooled using an air jet. Commercial disc-making machines use this method. Whatever the method of cooling, it is vital that samples be treated identically, as the curvature of the analytical surface of the disc depends on the rate of cooling. 4.11 Laboratory glass ware, one-mark pipettes (0,5 ml and 1,0 ml) and a one-mark 1 000 ml volumetric flask complying with the specifications of ISO 648 or ISO 1042, r