1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 20884:2011 BS 2000-497:2011Petroleum products Determination of sulfur content of automotive fuels Wavelength-dispersive X-ray fluorescence spectrometry (ISO 20884:2011)
2、Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 20884:2011. It supersedes BS EN ISO 20884:2004, which is withdrawn.The UK participation in
3、 its preparation was entrusted to Technical Committee PTI/13, Petroleum Testing and Terminology.A list of organizations represented on this committee can be obtained on request to its secretary.Energy Institute, under the brand of IP, publishes and sellsall Parts of BS 2000, and all BS EN petroleum
4、test methodsthat would be Part of BS 2000, both in its annual publication“Standard methods for analysis and testing of petroleumand related products and British Standard 2000 Parts” andindividually. Further information is available from: Energy Institute, 61 New Cavendish Street, London W1G7AR. Tel:
5、 020 7467 7100. Fax: 020 7255 1472.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. BSI 2011 ISBN 978 0 580 68201 8 ICS 75.080; 75.160.30 Compliance with a British Standard cannot confer immunity from legal ob
6、ligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2011.Amendments issued since publicationDate Text affectedLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIEUROPEAN STANDARD NO
7、RME EUROPENNE EUROPISCHE NORM EN ISO 20884 April 2011 ICS 75.160.30; 75.080 Supersedes EN ISO 20884:2004English Version Petroleum products - Determination of sulfur content of automotive fuels - Wavelength-dispersive X-ray fluorescence spectrometry (ISO 20884:2011) Produits ptroliers - Dtermination
8、de la teneur en soufre des carburants pour automobiles - Spectromtrie de fluorescence de rayons X dispersive en longueur donde (ISO 20884:2011) Minerallerzeugnisse - Bestimmung des Schwefelgehaltes in Kraftstoffen fr Kraftfahrzeuge - Wellenlngendispersive Rntgenfluoreszenz-Spektrometrie (ISO 20884:2
9、011) This European Standard was approved by CEN on 14 April 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical
10、references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of
11、a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary
12、, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre:
13、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. EN ISO 20884:2011: ELicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011ISO 2088
14、4:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv 1 Scope1 2 Normative references1 3 Principle .1 4 Reagents 2 5 Apparatus.2 6 Sampling 3 7 Calibration solutions.3 8 Settings.4 9 Calibration4 10 Procedure.5 11 Expression of results6 12 Precision 6 13 Test report7 Annex A (informati
15、ve) Interferences and matrix effects .8 Bibliography9 Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011ISO 20884:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwi
16、de federation of national standards bodies (ISO member bodies). The work of preparing International 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 tha
17、t committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in a
18、ccordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard re
19、quires 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 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 20884 was prepared by Techn
20、ical Committee ISO/TC 28, Petroleum products and lubricants. This second edition cancels and replaces the first edition (ISO 20884:2004), which has been technically revised. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011INTERNA
21、TIONAL STANDARD ISO 20884:2011(E) ISO 2011 All rights reserved 1Petroleum products Determination of sulfur content of automotive fuels Wavelength-dispersive X-ray fluorescence spectrometry WARNING The use of this International Standard may involve hazardous materials, operations and equipment. This
22、International Standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this International Standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1 Sc
23、ope This International Standard specifies a wavelength-dispersive X-ray fluorescence (WDXRF) test method for the determination of the sulfur content of liquid, homogeneous automotive fuels from 5 mg/kg to 500 mg/kg, which have a maximum oxygen content of 3,7 % (m/m). This product range covers diesel
24、 fuels containing up to about 10 % (V/V) fatty acid methyl esters (FAME) and motor gasolines containing up to about 10 % (V/V) ethanol. NOTE 1 Sulfur contents higher than 500 mg/kg can be determined after sample dilution. However, the precision was not established for diluted samples. Products with
25、higher oxygen content show significant matrix effects, e.g. FAME used as biodiesel. Nevertheless, FAME may be analysed when the corresponding procedures are followed (see 4.3 and 7.1). Other products may be analysed with this test method. However, precision data for products other than those mention
26、ed have not been established for this International Standard. NOTE 2 For the purposes of this International Standard, the terms “% (m/m)” and “% (V/V)” are used to represent the mass fraction and the volume fraction of a material respectively. 2 Normative references The following referenced document
27、s are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3170, Petroleum liquids Manual sampling ISO 3171, Petroleum liquids Automatic
28、pipeline sampling 3 Principle The sample under analysis is exposed in a sample cell to the primary radiation of an X-ray tube. The count rates of the S K-L2,3X-ray fluorescence and, where required, the count rate of the background radiation are measured. The sulfur content of the sample is determine
29、d from a calibration curve defined for the relevant measuring range. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011ISO 20884:2011(E) 2 ISO 2011 All rights reservedNOTE The IUPAC X-ray line notation (S K-L2,3) is used in this In
30、ternational Standard; the corresponding Siegbahn X-ray line notation (S-K) is being phased out. 4 Reagents 4.1 Dibutylsulfide, of nominal sulfur content 21,92 % (m/m), or dibutyldisulfide, of nominal sulfur content 35,95 % (m/m), used as a calibrating substance for sulfur. Care should be taken due t
31、o volatility (see Annex A). 4.2 White oil (paraffinum perliquidum), for use as a blank solution, of high purity grade, with a sulfur content of less than 1 mg/kg. Check the blank solution prior to use with the spectrometer (5.1). A signal for sulfur shall not be detectable. 4.3 Methyl oleate, for us
32、e as a blank solution when FAME is analysed, with a sulfur content of less than 1 mg/kg. Check the blank solution prior to use with the spectrometer (5.1). A signal for sulfur shall not be detectable (i.e. the intensity shall be lower that the intensity equivalent to 1 mg/kg). Other oxygen-containin
33、g and sulfur-free blank solutions, such as octanol, can also be used. 5 Apparatus 5.1 Wavelength-dispersive X-ray fluorescence spectrometer, with the capability for measuring the count rates of the S K-L2,3X-ray fluorescence radiation and the background radiation. Due to the inherently low backgroun
34、d radiation produced by instruments utilizing monochromatic radiation for excitation, it is not mandatory to measure the background radiation when this type of instrument is used. The minimum requirements for the spectrometer are given in Table 1. Table 1 Spectrometer requirements Component Polychro
35、matic excitation Monochromatic excitation Anode Rhodium, scandium or chromium Rhodium, scandium, chromium or titanium VoltageaNo less than 30 kV No less than 30 kV CurrentaNo less than 50 mA No less than 0,1 mA Collimator or optic Coarse collimator Monochromator Analysing crystal Germanium, pentaery
36、thrite or graphite Germanium, pentaerythrite or graphite Optical pathbVacuum or helium Vacuum or helium Sample cup windowcPolyester film, 4 m maximum Polyester film, 4 m maximum Detector Proportional counter with pulse-height analyser Proportional counter with single channel analyser Wavelengths S K
37、-L2,3at 0,537 3 nm Background radiation at 0,545 nm S K-L2,3at 0,537 3 nm aLower-power systems may be used, provided they have been validated to meet the precision requirements specified in Clause 12. bIn instruments using vacuum, the sample is not exposed directly to the vacuum of the optical path,
38、 but is separated by a secondary window. cPolyester film is the preferred choice as samples of very high aromatic content may dissolve polycarbonate film. There are possibly trace amounts of silicon, calcium and sulfur in some types of film. However, the effects should be cancelled out when samples
39、and standards are analysed using the same batch of film. It is important that samples, standards and blanks be measured using the same batch of film to avoid bias. Other sample window materials with the same or better absorptivity, purity and stability can also be used. Licensed Copy: Wang Bin, ISO/
40、EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011ISO 20884:2011(E) ISO 2011 All rights reserved 35.2 Analytical balance, capable of weighing to the nearest 0,1 mg. 6 Sampling Unless otherwise specified, samples shall be taken by the procedures described in IS
41、O 3170 or ISO 3171. 7 Calibration solutions 7.1 Blank solution Use white oil (4.2) as a blank solution. If FAME is under analysis, use a blank solution in accordance with 4.3 to minimize potential matrix effects. 7.2 Stock solution Weigh a quantity of the required calibrating substance (4.1) to the
42、nearest 0,1 mg, and dilute with blank solution (4.2 or 4.3, as appropriate) at room temperature so that a stock solution with an accurately known sulfur content (to the nearest 1 mg/kg) of approximately 1 000 mg/kg is obtained. Care should be taken due to volatility of the calibrating substance (see
43、 Annex A). 7.3 Calibration solutions Weigh an appropriate quantity of the stock solution (7.2) to the nearest 0,1 mg into bottles and dilute with blank solution (4.2 or 4.3, as appropriate) so that standard solutions with sulfur contents in accordance with Tables 2 and 3 are obtained by stirring at
44、room temperature. The sulfur contents in the calibration solutions are indicated in milligrams per kilogram, rounded to the nearest 0,1 mg/kg. Table 2 Calibration solutions Low sulfur range Number Sulfur content mg/kg Blank solution 0 0,0 2,1 5,0 2,2 10,0 2,3 25,0 2,4 50,0 Table 3 Calibration soluti
45、ons High sulfur range Number Sulfur content mg/kg Blank solution 0 0,0 3,1 50,0 3,2 100,0 3,3 200,0 3,4 350,0 3,5 500,0 Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 10/08/2011 02:54, Uncontrolled Copy, (c) BSIBS EN ISO 20884:2011ISO 20884:2011(E) 4 ISO 2011 All rights reserved7.4 Storage a
46、nd stability of the calibration solutions Calibration solutions prepared in accordance with Table 2 have a limited stability and shall be used on the day they are prepared. Calibration solutions prepared in accordance with Table 3 have a stability of no more than one week if stored in a cool locatio
47、n (refrigerator). 8 Settings 8.1 Measuring parameters For optimum measuring parameters, refer to Table 1. 8.2 Optimization The spectrometer shall be optimized in accordance with the manufacturers specifications in order to achieve the optimum signal-to-noise ratio. The calibration solution with 50 m
48、g/kg sulfur is recommended for optimization. The counting time shall be set so that the total net count from a 50 mg/kg solution is W 40 000. This counting time shall be used for both calibration (see Clause 9) and measurement (see Clause 10). 8.3 Performance check of the spectrometer Prior to a mea
49、surement series (calibration and/or measurement), but in any case at least once daily, the manufacturers specifications shall be used to check that the spectrometer is operating correctly, so that an optimum performance and a consistent standard of highest possible quality is ensured. Performance checks should be carried out on a regular basis, since such checks give valuable information about the status and stability of the spectrometer. 9 Calibration 9.1 General Ensure that the spectrometer is in an optimized cond
