DIN 51363-2-2003 Testing of petroleum products - Determination of phosphorus content of lubricating oils and additives - Part 2 Analysis by wavelength dispersive X-ray spectrometry.pdf

1、ICS 75.100Prfung von Minerallen Bestimmung des Phosphorgehaltesvon Schmierlen und Schmierl-Wirkstoffen Teil 2:Wellenlngendispersive Rntgenfluoreszenz-Analyse (RFA)In keeping with current practice in standards published by the International Organization for Standardization(ISO), a comma has been used

2、 throughout as the decimal marker.Ref. No. DIN 51363-2 : 2003-02English price group 06 Sales No. 010604.04DEUTSCHE NORM February 2003 No part of this translation may be reproduced without the prior permission ofDIN Deutsches Institut fr Normung e.V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,

3、has the exclusive right of sale for German Standards (DIN-Normen).Translation by DIN-Sprachendienst.In case of doubt, the German-language original should be consulted as the authoritative text.Determining the phosphorus content of lubricatingoils and additives by wavelength-dispersive X-rayfluoresce

4、nce spectrometryDocument comprises 4 pages.Supersedes DIN 51363-2,September 1987 edition.51363-2ForewordThis standard has been prepared by Technical Committee Rntgenfluoreszenz-Analyse of the Fachaus-schuss Minerall- und Brennstoffnormung of the Normenausschuss Materialprfung (Materials TestingStand

5、ards Committee).AmendmentsThis standard differs from the September 1987 edition as follows:a) the scope has been modified to cover phosphorus contents ranging from 0,001 g/100 g to 1 g/100 g;b) details of testing have been changed;c) the standard has been editorially revised and references updated.P

6、revious editionsDIN 51363-2: 1980-11, 1987-09.1 ScopeThis standard specifies a method of determining phosphorus contents ranging from 0,001 g/100 g to1 g/100 g (i.e. 0,001% (m/m) to 1% (m/m) in homogeneous liquid petroleum products having an initialboiling point of over 150 C and in synthetic oils a

7、nd additives containing phosphorus in an oil-soluble form.The range can be extended by suitable dilution, but the precision data given is valid only for contents upto 0,005%.2 Normative referencesThis standard incorporates, by dated or undated reference, provisions from other publications. Thesenorm

8、ative references are cited at the appropriate places in the text, and the titles of the publications arelisted below. For dated references, subsequent amendments to or revisions of any of these publicationsapply to this standard only when incorporated in it by amendment or revision. For undated refe

9、rences, thelatest edition of the publication referred to applies.DIN 51418-1 X-ray emission and X-ray fluorescence analysis General concepts and basic principlesDIN 51418-2 X-ray emission and X-ray fluorescence analysis Terminology and principles of measure-ment, calibration and evaluationPage 2DIN

10、51363-2 : 2003-02DIN 51750-1 Sampling of petroleum products GeneralDIN 51750-2 Sampling of liquid petroleum productsDIN EN ISO 3170 Petroleum liquids Manual sampling (ISO 3170 : 1988 + A1 : 1998)DIN EN ISO 4259 Petroleum products Determination and application of precision data in relation to meth-od

11、s of test (ISO 4259 : 1992 + Corr 1 : 1993)3 PrincipleA mixture of ten parts by mass of the sample to be analysed and one part by mass of zirconium referencesolution is exposed in a sample vessel to the primary radiation of an X-ray tube. The count rates of thephosphorus Kaand zirconium La1X-ray flu

12、orescence radiation thus emitted are measured and used to calculatethe count rate ratio. The phosphorus content of the sample is determined from calibration graphs prepared onthe basis of phosphorus reference solutions.The method is generally applicable to sample material of any composition, irrespe

13、ctive of the type of phospho-rus compounds detected and of any other elements they contain.NOTE: This method cannot be used if precipitates occur when the internal standard is added, as in the caseof polyglycols. It may be possible to eliminate such precipitates by further dilution or by adding a so

14、lubilizer(e.g. xylene).4 ApparatusIn addition to standard laboratory equipment, the following shall be used.4.1 Wavelength-dispersive X-ray spectrometer (cf. DIN 51418 series), capable of measuring the countrates of phosphorus Kaand zirconium La1 X-ray fluorescence radiations and having the followin

15、g parameters.a) X-ray tube, meeting the following requirements:Anode: chromium, rhodium or scandium.Voltage: at least 50 kV.Current: at least 20 mA.b) Collimator aperture: wide.c) Analyser crystal: germanium1).d) X-ray path: helium.e) Detector: flow-proportional counter, with pulse height analyser.O

16、ther spectrometers may be used and the above parameters may be modified provided that regular compara-tive measurements demonstrate that the precision specified in this standard is achieved and interferences due,for example, to sulfur or calcium are taken into account.4.2 Balance, with 0,1 mg scale

17、intervals.4.3 Stirrer, capable of being heated.4.4 Polypropylene film, phosphorus-free, 6,3 mm thick, used for lining the sample beaker.5 ReagentsThe following reagents shall be used.5.1 Paraffinum perliquidum, as in the European Pharmacopoeia.5.2 Tri-n-butyl phosphate, C12H27O4P, or any other oil-s

18、oluble phosphorus compound of known phospho-rus content.5.3 12% to 18% (m/m) zirconium solution, containing zirconium octoate or any other oil-soluble zirconiumcompound.5.4 1% (m/m) phosphorus stock solution, prepared by dissolving the requisite quantity of tri-n-butyl phos-phate or any other oil-so

19、luble phosphorus compound in paraffinum perliquidum.5.5 2-ethylhexanoic acid, phosphorus-free, for stabilizing the zirconium solution, if necessary.1) Using a germanium crystal completely suppresses the (often troublesome) second-order Ca-Kbradiation.Page 3DIN 51363-2 : 2003-026 SamplingAs in DIN 51

20、750-1, DIN 51750-2 or DIN EN ISO 3170.7 Plotting the calibration graph7.1 Zero member compensation solutionUse paraffinum perliquidum as zero member compensation solution.7.2 Checking the polypropylene filmRecord the X-ray spectrum with the zero member compensation solution using the polypropylene f

21、ilm in the0,603 nm to 0,625 nm spectral range. If any phosphorus peak that is visible exceeds the noise by a factor oftwo or more, discard the film. Repeat this check every time the batch of film is replaced.7.3 Reference solutionsDilute the phosphorus stock solution with paraffinum perliquidum whil

22、e stirring and heating to not more than80 C to obtain solutions having phosphorus contents of 0,001%, 0,005%, 0,01%, 0,03%, 0,06%, 0,1%,0,4%, 0,8% g and 1%, weighing in all cases to an accuracy of 0,1 mg.If the phosphorus concentration is to be determined in only part of the range covered by all ten

23、 of the abovereference solutions, fewer solutions, but not less than four, may be used to plot the calibration graph.7.4 Calibration solutionsAdd one part by mass (e.g. 2 g) of zirconium solution to ten parts by mass (e.g. 20 g) of each phosphorusreference solution and to the zero member compensatio

24、n solution, and then homogenize the solutions bystirring and heating to not more than 80 C.7.5 Measurement of count ratesAfter cooling the calibration solutions to ambient temperature, transfer them to sample vessels and exposethem consecutively to the primary radiation of the X-ray tube. Measure th

25、e count rates of the P-Kafluorescenceradiation at 0,615 5 nm, IP, and the Zr-La1fluorescence radiation at 0,607 0 nm, IZr. Adjust the equipment sothat the Zr-La1line count is at least 40 000 throughout the period of measurement.Calculate the count rate ratio, R, for every calibration solution, using

26、 the following equation:R = IP/IZr(1)7.6 Calibration graphPlot the count rate ratio of the individual calibration solutions as a function of the phosphorus content. If theentire range cannot be covered in a single graph, divide the calibration graph into two sections. Check thecalibration graph obta

27、ined at least every six months.NOTE: Many modern spectrometers are equipped with a computer that stores calibration graphs and outputsthe required contents directly.8 Procedure8.1 Add one part by mass (e.g. 2 g) of zirconium solution to ten parts by mass (e.g. 20 g) of sample materialto be analysed

28、and homogenize the solution while stirring and heating to not more than 80 C. Cool to ambienttemperature and determine the count rate ratio, R, as specified in subclause 7.5 for the sample thus prepared.8.2 Calculate the phosphorus content of the sample, in g/100 g or as a percentage by mass, for th

29、e count rateratio determined as in subclause 7.5 using the calibration graph. If the phosphorus content is beyond thecalibration range, suitably dilute the sample with paraffinum perliquidum and repeat the measurement.9 Expression of resultRefer to this standard and report the phosphorus content in

30、g/100 g or as a percentage by mass, rounding theresults as indicated in table 1.Page 4DIN 51363-2 : 2003-0210 Precision(cf. DIN EN ISO 4259)10.1 Repeatability limit(same operator, same equipment)The absolute difference between two successive results obtained under repeatability conditions will not e

31、xceedthe values in table 1 in more than 5% of cases.10.2 Reproducibility limit(different operators, different equipment)The absolute difference between two individual results obtained under reproducibility conditions will notexceed the values in table 1 in more than 5% of cases.Table 1: Repeatabilit

32、y and reproducibility limits11 Test reportThe test report shall refer to this standard and include the following details as a minimum:a) type and identification of product to be tested;b) method of sampling used;c) test result;d) any deviation from the specified method;e) date of testing.Phosphorus content, Repeatability limit, Reproducibility limit,as a percentage by mass as a percentage by mass as a percentage by mass0,005 to 0,05 0,001 0,002Over 0,05 up to 0,5 0,005 0,01Over 0,5 up to 1,0 0,01 0,02