1、November 2007DEUTSCHE NORM English price group 8No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 75.160.20!$J3+“1391608
2、www.din.deDDIN EN 15485Ethanol as a blending component for petrol Determination of sulfur content Wavelength dispersive X-ray fluorescence spectrometric methodEnglish version of DIN EN 15485:2007-11Ethanol zur Verwendung als Blendkomponente in Ottokraftstoff Bestimmung des Schwefelgehaltes Wellenlng
3、endispersive Rntgenfluoreszenz-Spektrometrie (wdRFA)Englische Fassung DIN EN 15485:2007-11www.beuth.deDocument comprises 11 pagesDIN EN 15485:2007-11 2 National foreword This standard has been prepared by Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of pet
4、roleum, synthetic and biological origin” (Secretariat: NEN, Netherlands). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NA 062-06-81 AA Gasfrmige und flssige Kraft- und Brennstoffe, Schmiers
5、toffe und verwandte Produkte mit minerallstmmiger, synthetischer oder biologischer Herkunft of the Fachausschuss Minerall- und Brennstoffnormung (FAM). EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 15485August 2007ICS 71.080.60English VersionEthanol as a blending component for petrol - Determina
6、tion ofsulfur content - Wavelength dispersive X-ray fluorescencespectrometric methodsoufre - Mthode par fluorescence X dispersive en longueurdondeEthanol zur Verwendung als Blendkomponente inOttokraftstoff - Bestimmung des Schwefelgehaltes -Wellenlngendispersive Rntgenfluoreszenz-Spektrometrie(wdRFA
7、)This European Standard was approved by CEN on 30 June 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical referen
8、ces concerning such nationalstandards may be obtained on application to the CEN 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 translationunder the responsibility of a CEN member into
9、its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lit
10、huania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CE
11、N All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15485:2007: Ethanol comme base de mlange lessence - Dosage duEN 15485:2007 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Reagents and materials 4 5 Appar
12、atus .4 6 Samples and sampling5 7 Preparation of calibration solutions 5 7.1 Blank calibration solution.5 7.2 Stock solution 5 7.3 Calibration solutions .5 7.4 Storage and stability of the calibration solutions 6 8 Settings.6 8.1 Measuring parameters 6 8.2 Optimization .6 8.3 Performance check of th
13、e spectrometer.6 9 Calibration 6 9.1 General6 9.2 Calibration solutions .7 9.3 Calibration curves7 9.4 Checking.7 10 Procedure .7 11 Expression of results 8 12 Precision.8 12.1 Repeatability.8 12.2 Reproducibility.8 13 Test report 8 Bibliography 9 EN 15485:2007 (E) 3 Foreword This document (EN 15485
14、:2007) has been prepared by Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biological origin”, the secretariat of which is held by NEN. This European Standard shall be given the status of a national standard, either by publication
15、 of an identical text or by endorsement, at the latest by February 2008, and conflicting national standards shall be withdrawn at the latest by February 2008. The method described in this document is based on EN ISO 20884 1. According to the CEN/CENELEC Internal Regulations, the national standards o
16、rganizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal
17、, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 15485:2007 (E) 4 1 Scope This document specifies a wavelength-dispersive X-ray fluorescence (WDXRF) test method for the determination of the sulfur content of ethanol from 7 mg/kg to 20 mg/kg. NOTE For the purposes of t
18、his European Standard, the term “% (m/m)“ is used to represent the mass fraction of a material. 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 e
19、dition of the referenced document (including any amendments) applies. EN ISO 3170, Petroleum liquids Manual sampling (ISO 3170:2004) 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 X-ray fluorescence and the coun
20、t rate of the background radiation are measured. The sulfur content of the sample is determined from a calibration curve defined for the relevant measuring range. NOTE Whilst the Siegbahn X-ray line notation (S-K) is used in this document, the corresponding IUPAC X-ray line notation is S K-L2,3. 4 R
21、eagents and materials 4.1 Dibutylsulfide, of nominal sulfur content 21,92 % (m/m), or 4.2 Dibutyldisulfide, of nominal sulfur content 35,95 % (m/m), used as a calibrating substance for sulfur. 4.3 Ethanol absolute, where the purity is not less than 99 %, for use as a blank solution, high purity grad
22、e, with a sulfur content 1 mg/kg. Check the blank solution prior to use with the spectrometer (5.1). A signal for sulfur shall not be detectable. 5 Apparatus 5.1 Wavelength dispersive X-ray fluorescence spectrometer, with the capability for measuring the count rates of the S-K X-ray fluorescence rad
23、iation and the background radiation. The minimum requirements for the spectrometer are given in Table 1. EN 15485:2007 (E) 5 Table 1 Spectrometer requirements Component Requirement Recommendations Anode Rhodium, scandium or chromium Voltagea)No less than 30 kV 30 kV Currenta) No less than 50 mA 100
24、mA Collimator Coarse Analysing crystal Germanium, pentaerythrite, or graphite Germanium Optical path Helium Sample cup windowb)Polyester film, sulfur-free, 4 m maximum Polyester film 3,5 m Detector Proportional counter with pulse-height analyser aLower power systems may be used, provided that these
25、have been validated to meet the precision requirements specified in Clause 12. bOther sample window materials with the same or better transparency, purity and stability, can also be used.5.2 Analytical balance, capable of weighing to the nearest 0,1 mg. 6 Samples and sampling Unless otherwise specif
26、ied, laboratory samples shall be obtained by the procedures described in EN ISO 3170. High density polyethylene containers shall be used. The containers should be carefully cleaned and rinsed with pure water to avoid contamination. Samples should be analysed as soon as possible after removal from bu
27、lk supplies to prevent loss of sulfur. Thoroughly mix samples in their containers immediately prior to withdrawal of the test portions. NOTE Particular attention should be paid to avoid contamination of sampling bottles from phosphorus containing detergents. 7 Preparation of calibration solutions 7.
28、1 Blank calibration solution Use ethanol (4.3) as a blank solution. 7.2 Stock solution Weigh a quantity of the required calibrating substance (4.1 or 4.2) to the nearest 0,1 mg, and dilute with blank solution (7.1) at room temperature so that a stock solution with an accurately known sulfur content
29、(to the nearest 1 mg/kg) of approximately 1 000 mg/kg is obtained. NOTE Care should be taken due to volatility of the calibrating substance. 7.3 Calibration solutions Weigh the stock solution (7.2) to the nearest 0,1 mg into bottles and dilute with blank solution (7.1) so that standard solutions wit
30、h sulfur contents in accordance with Table 2 are provided by stirring at room EN 15485:2007 (E) 6 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 Number Sulfur content mg/kg 0 (blan
31、k solution) 0,0 1 5,0 2 10,0 3 20,0 7.4 Storage and stability of the calibration solutions Calibration solutions prepared in accordance with Table 2 have a limited stability and shall be used on the same day they are prepared. NOTE While stock solutions may be stable for a longer time, calibration s
32、olutions may not. 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 20 m
33、g/kg sulfur is recommended for optimization. The counting time shall be adjusted such that, for the 20 mg/kg calibration solutions, an optimal signal-to-noise ratio and signal area, for example resulting from 15 000 net counts, is obtained. This optimized counting time shall be used for both calibra
34、tion (see 9) and measurement (see 10). 8.3 Performance check of the spectrometer Prior to a measurement 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 optim
35、um performance and a consistent standard of highest possible quality is ensured. NOTE 1 Many modern WDXRF systems use drift monitoring and correction to ensure that systems produce accurate data over long periods of time without the need to recalibrate. NOTE 2 Performance checks should be performed
36、on a regular basis, since such checks will give valuable information about the status and stability of the spectrometer. 9 Calibration 9.1 General Take care to ensure that the spectrometer is in an optimized condition after having executed all provisions given in Clause 8 and operating optimally bef
37、ore calibration (see 8.3). EN 15485:2007 (E) 7 9.2 Calibration solutions Transfer the calibration solutions (7.3) into suitable sample cups and fill them half full (see the note below). Depending on the concentration range, all calibration solutions prepared in accordance with Table 2 shall be measu
38、red consecutively in ascending order. The count rate, Is, of the S-K X-ray fluorescence radiation at 0,537 3 nm, and the count rate, IB, of the background radiation at 0,545 nm, shall be measured consecutively. NOTE Too small sample quantities will give a low result or relatively more evaporation/co
39、ncentration effects when measuring volatile samples, whilst too much quantity of sample will give more sagging of the cell window especially when light aromatic samples are measured. 9.3 Calibration curves The net count rate, I0, is calculated according to equation (1). To determine the calibration
40、curve, the relevant net count rate, I0, is plotted against the corresponding sulfur content of the calibration solution; the calibration curve shall then be calculated and stored using the linear model according to equation (2). The regression calculation may be carried out either separately or usin
41、g the spectrometer calculator. I0BSII = (1) where I0is the net count rate for the relevant determination; Isis the count rate of the S-K X-ray fluorescence radiation at 0,537 3 nm; IBis the count rate of the background radiation at 0,545 nm; () bxaxI +=0(2) where x is the sulfur content of the relev
42、ant calibration solution, expressed in milligrams per kilogram (mg/kg); a, b are the parameters from the regression calculation; I0(x) is the net count rate computed from the regression calculation for the content, x. 9.4 Checking Check the WDXRF system daily or before a measurement series by using
43、quality control samples with known sulfur contents. Check immediately when using a new batch of films. If the check result differs by more than the 0,71 R, where R is the reproducibility of this test method (see 12.2), execute a recalibration. NOTE It is recommended to execute a control chart analys
44、is. 10 Procedure Fill a sample cup with a sufficient quantity of the sample under analysis so that an approximate medium height level is achieved (see the note to 9.2). Expose the sample to the radiation of the X-ray tube. Measure consecutively the count rate, Is, of the S-K X-ray fluorescence radia
45、tion at 0,537 3 nm and the count rate, IB,of the background radiation at 0,545 nm. Calculate the net count rate, I0, according to equation (1). Read the sulfur content in milligrams per kilogram from the calibration curve (see 9.3) for the measuring range of 7 mg/kg to 20 mg/kg sulfur. If the sulfur
46、 content EN 15485:2007 (E) 8 is higher than 20 mg/kg, then a new sample in a new cup shall be measured using a sample obtained by appropriate dilution with the blank solution (7.1). 11 Expression of results Report the sulfur content of the sample to the nearest 0,1 mg/kg. 12 Precision NOTE The preci
47、sion given was determined by statistical examination of interlaboratory test results using EN ISO 4259 2. 12.1 Repeatability The difference between two successive test results obtained by the same operator with the same apparatus under constant operating conditions on identical test material would,
48、in the normal and correct operation of the test method, exceed the value given below only in one case in twenty: r = 0,04 X + 1,82 (3) where X is the average of the two results being compared, in mg/kg. 12.2 Reproducibility The difference between two single and independent results obtained by differ
49、ent operators working in different laboratories on nominally identical test material would, in the normal and correct operation of the test method, exceed the value given below only in one case in twenty: R = 0,07 X + 3,26 (4) where X is the average of the two results being compared, in mg/kg. 13 Test report The test report shall contain at least the following information: a) type and identification of the product under test; b) reference to this European standard, i.e. EN 15485; c) result of the test (see 11); d) any deviation from the proc
