DIN EN 15487-2007 Ethanol as a blending component for petrol - Determination of phosphorus content - Ammonium molybdate spectrometric method English version of DIN EN 15487 2007-11.pdf

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!$J30“1391613

2、www.din.deDDIN EN 15487Ethanol as a blending component for petrol Determination of phosphorus content Ammonium molybdate spectrometric methodEnglish version of DIN EN 15487:2007-11Ethanol zur Verwendung als Blendkomponente in Ottokraftstoff Bestimmung des Phosphorgehaltes Spektrometrisches Verfahren

3、 mit AmmoniummolybdatEnglische Fassung DIN EN 15487:2007-11www.beuth.deDocument comprises 11 pagesDIN EN 15487:2007-11 2 National foreword This standard has been prepared by Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biologica

4、l 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, Schmierstoffe und verwandte Produkte mi

5、t minerallstmmiger, synthetischer oder biologischer Herkunft of the Fachausschuss Minerall- und Brennstoffnormung (FAM). EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 15487August 2007ICS 71.080.60English VersionEthanol as a blending component for petrol - Determination ofphosphorus content - Amm

6、onium molybdate spectrometricmethodthanol comme base de mlange lessence -Dtermination de la teneur en phosphore - Mthodespectromtrique au molybdate dammoniumEthanol zur Verwendung als Blendkomponente inOttokraftstoff - Bestimmung des Phosphorgehaltes -Spektrometrisches Verfahren mit Ammoniummolybdat

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 referenc

8、es 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 i

9、ts 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, Lith

10、uania, 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 CEN

11、 All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15487:2007: EEN 15487:2007 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Reagents and materials 4 5 Apparatus .5 6 Samples and sampling6 7 Calibration 6 7

12、.1 Preparation of calibration solutions 6 7.2 Colour development 6 7.3 Spectrometric measurement 6 7.4 Calibration regression line .6 8 Procedure .7 8.1 Dry residue .7 8.2 Test portion 7 8.3 Colour development 7 8.3 Spectrometric measurement 7 9 Calculation7 10 Expression of results 7 11 Precision.8

13、 11.1 Repeatability.8 11.2 Reproducibility.8 12 Test report 8 Bibliography 9 EN 15487:2007 (E) 3 Foreword This document (EN 15487:2007) has been prepared by Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biological origin”, the se

14、cretariat of which is held by NEN. This European Standard shall be given the status of a national standard, either by publication 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 d

15、escribed in this document is based on EN ISO 6878 1 and a method from a European Regulation on wine 2. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus,

16、 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 United Kingdom. EN 15487:2007 (E) 4 1 Scope This standard sp

17、ecifies a procedure for the determination of phosphorus content measured as orthophosphate, in ethanol from 0,15 mg/l to 1,50 mg/l by ammonium molybdate spectrometric method. The phosphorus content is determined in aqueous solution after dissolution of the evaporation residue of the ethanol sample.

18、WARNING Use of this standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to dete

19、rmine the applicability of regulatory limitations prior to use. 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 referenced documen

20、t (including any amendments) applies. EN ISO 3170, Petroleum liquids Manual sampling (ISO 3170:2004) EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696:1987) 3 Principle After evaporation of the ethanol sample, the dry residue is dissolved in water. The aqueous

21、 solution is treated with an acid solution containing molybdate and antimony ions to obtain an antimony phosphomolybdate complex. The complex is then treated with ascorbic acid to form a strongly coloured molybdenum blue complex. The content of phosphorus is obtained by measuring the absorbance of t

22、he complex at 880 nm. 4 Reagents and materials 4.1 All reagents shall be of analytical reagent grade or of higher purity. 4.2 Water, for analytical laboratory use, conforming to grade 3 of ISO 3696. 4.3 Sulphuric acid solution, c(H2SO4) 9 mol/l Add 500 ml 5 ml water (4.2) to a 2 l beaker. Cautiously

23、 add, with continuous stirring and cooling, 500 ml 5 ml sulphuric acid, = 1,84 g/ml. Mix well and allow the solution to cool to room temperature. 4.4 Hydrochloric acid solution, c(HCl) 2,4 mol/l Cautiously add in a 1 000 ml volumetric flask (5.4), 200 ml 10 ml of concentrated hydrochloric acid ( = 1

24、,18 g/ml) to 500 ml 10 ml water (4.2). Mix and cool to room temperature. Make up to 1 000 ml with water (4.2). 4.5 Sodium hydroxide solution, c(NaOH) = 2 mol/l Dissolve 80 g 1 g sodium hydroxide pellets in water (4.2) in a 1 000 ml volumetric flask (5.4), cool and dilute to 1 l with water (4.2). 4.6

25、 Ascorbic acid solution, c(C6H8O6) = 100 g/l Dissolve 10 g 0,5 g ascorbic acid in 100 ml 5 ml water (4.2). NOTE The solution is stable for 2 weeks if stored in an amber glass bottle in a refrigerator and can be used as long as it remains colourless. EN 15487:2007 (E) 5 4.7 Acid molybdate solution Di

26、ssolve 13 g 0,5 g ammonium heptamolybdate tetrahydrate (NH4)6Mo7O244H2O in 100 ml 5 ml water (4.2). Dissolve 0,35 g 0,05 g antimony potassium tartrate hemihydrate K(SbO)C4H4O6H2O in 100 ml 5 ml water (4.2). Add the molybdate solution to 300 ml 5 ml sulphuric acid (4.3) with continuous stirring. Add

27、the tartrate solution and mix well. NOTE The reagent is stable for at least 2 months if stored in an amber glass bottle. 4.8 Orthophosphate stock standard solution, c(P) = 50 mg/l Dry a few grams of potassium dihydrogen phosphate (KH2PO4) to constant mass at 105 C. Weigh about 0,220 g of KH2PO4with

28、a precision of 0,000 1 g and dissolve in about 800 ml 10 ml water (4.2) in a 1 000 ml volumetric flask. Add 10 ml 0,5 ml sulphuric acid (4.3) and make up to the mark with water (4.2). Alternatively, use a commercially available stock solution. NOTE The solution is stable for at least 3 months if sto

29、red in a well stopped glass bottle. Refrigeration to about 4 C is recommended. 4.9 Orthophosphate standard solution, c(P) = 2 mg/l Pipette 20 ml 0,01 ml orthophosphate stock standard solution (4.8) into a 500 ml volumetric flask. Make up to the mark with water (4.2) and mix well. Prepare and use thi

30、s solution each day as required. 5 Apparatus 5.1 Water bath 5.2 Evaporating dish, capacity 100 ml to 250 ml. 5.3 Volumetric pipettes , Class A. 5.4 Volumetric flasks, Class A. 5.5 Burettes, calibrated burettes of 10 ml and 50 ml capacity with 0,05 ml and 0,1 ml subdivision respectively. 5.6 Desiccat

31、or, containing freshly activated silica gel (or equivalent desiccant) with moisture content indicator. 5.7 Oven, thermostatically controlled at (105 2) C. 5.8 Spectrometer, suitable for measuring absorbance at 880 nm and capable of accepting optical cells with a thickness 10 mm. 5.9 Laboratory glass

32、ware Before use, wash all glassware, for example with hydrochloric acid (4.4), at approximately 40 C to 50 C and rinse thoroughly with water (4.2). Detergents containing phosphate shall not be used. Preferably the glassware should be used only for the determination of phosphorus. After use, clean it

33、 as described above and keep covered until needed again. Rinse glassware used for the colour development and optical cells occasionally with sodium hydroxide solution (4.5), followed by thorough rinsing with water (4.2), to remove deposits of the coloured complex which has a tendency to stick as a t

34、hin film on the wall of glassware. EN 15487:2007 (E) 6 6 Samples and sampling Unless otherwise specified, 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 pu

35、re water to avoid contamination. Particular attention should be paid to avoid contamination from phosphorus containing detergents. Samples should be analysed as soon as possible after removal from bulk supplies to prevent possible loss of phosphorus. Thoroughly mix samples in their containers immedi

36、ately prior to withdrawal of the test portions. NOTE High density polyethylene containers are used in order to prevent losses of phosphorus by wall absorption. 7 Calibration 7.1 Preparation of calibration solutions Transfer, by means of a volumetric pipette (5.3), 2,5 ml, 5,0 ml, 10,0 ml, 20,0 ml, 3

37、0,0 ml, and 40,0 ml of orthophosphate standard solution (4.9) to 50 ml volumetric flasks. Dilute with water (4.2) to about 40 ml. As an alternative, volumes from 2,5 ml to 10,0 ml can be transferred using a 10 ml burette (5.5) and volumes from 20,0 ml to 40,0 ml using a 50 ml burette (5.5). Transfer

38、 about 40 ml of water (4.2) to a 50 ml volumetric flask (blank solution). 7.2 Colour development Add to each flask, while swirling, 1 ml of ascorbic acid (4.6) followed by 2 ml of acid molybdate solution (4.7). Make up to the mark with water (4.2) and mix well. Phosphorus concentration in the calibr

39、ation solutions is given in Table 1. Table 1 Phosphorus concentration of calibration solutions Calibration solution Orthophosphate solution ml Phosphorus concentration mg/l 1 (blank) 0 0 2 2,5 0,1 3 5,0 0,2 4 10,0 0,4 5 20,0 0,8 6 30,0 1,2 7 40,0 1,6 7.3 Spectrometric measurement Set up the spectrom

40、eter (5.8) according to the manufacturer instructions. Measure, using 10 mm cells, the absorbance of each solution at 880 nm after a period between 10 min and 30 min. Use water (4.2) in the reference cell. 7.4 Calibration regression line Plot the absorbance (as the y-axis) against phosphorus concent

41、ration in mg/l (as the x-axis) of the calibration solutions. The relationship between absorbance and concentration is linear. Calculate the linear regression EN 15487:2007 (E) 7 bXaY += (1) where Y is the absorbance; X is the phosphorus concentration in mg/l; a is the slope of the linear regression;

42、 b is the intercept of the linear regression. Verify the linear regression from time to time for slope and intercept, especially if new batches of chemicals are used. 8 Procedure 8.1 Dry residue Add (50 0,5) ml ethanol sample to the evaporating dish (5.2) using a 25 ml pipette (5.3). Place the dish

43、with sample on the water bath (5.1) and allow to dry. Place the dish in the oven (5.7) at 105 C for 30 minutes and then transfer the dish in a desiccator (5.6). Allow the dish to cool for 30 minutes. NOTE The time usually required to obtain the dry residue ranges from 2 hours to 3 hours. 8.2 Test po

44、rtion Add about 10 ml water (4.2) to the evaporating dish (5.2) and warm gently to solubilize the dry residue. Transfer the solution to a 50 ml volumetric flask (5.4). Repeat the treatment with 10 ml water (4.2) to rinse carefully the evaporating dish (5.2) and to transfer quantitatively the residue

45、. 8.3 Colour development Add to the flask, while swirling, 1 ml of ascorbic acid (4.6) followed by 2 ml acid molybdate solution (4.7). Make up to the mark with water (4.2) and mix well. 8.3 Spectrometric measurement Follow the procedure outlined in 7.3. 9 Calculation Calculate the phosphorus content

46、 P, expressed in mg/l, using the equation: abAP=(2) where A is the absorbance of the test portion; b is the intercept of the calibration regression (see 7.4); a is the slope of the calibration regression, expressed in l/mg (see 7.4). 10 Expression of results Report the phosphorus content in mg/l, ro

47、unded to the nearest 0,01 mg/l. EN 15487:2007 (E) 8 11 Precision NOTE The precision given was determined by statistical examination of interlaboratory test results using EN ISO 4259 3. 11.1 Repeatability The difference between two successive test results obtained by the same operator with the same a

48、pparatus under constant operating conditions on 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 = 0,03 X + 0,02 (3) where X is the average of the two results being compared, in mg/l. 11.2 Reproducibilit

49、y The difference between two single and independent results obtained by different 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 = 0,09 X + 0,06 (4) where X is the average of the two results being compared, in mg/l. 12 Test report The test report shall contain at least the following information: a) type and identification of the product under