DIN EN 15959-2012 Fertilizers - Determination of extracted phosphorus German version EN 15959 2011《肥料 萃取磷的测定 德文版本EN 15959-2011》.pdf

1、February 2012 Translation by DIN-Sprachendienst.English price group 9No part of this translation 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).IC

2、S 65.080!$y“1866188www.din.deDDIN EN 15959Fertilizers Determination of extracted phosphorusEnglish translation of DIN EN 15959:2012-02Dngemittel Bestimmung von Phosphor in den ExtraktenEnglische bersetzung von DIN EN 15959:2012-02Engrais Dosage du phosphore extraitTraduction anglaise de DIN EN 15959

3、:2012-02SupersedesDIN SPEC 1172(DIN CEN/TS 15959):2010-03www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1401.12 DIN EN 15959:2012-02 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Tec

4、hnical Committee CEN/TC 260 “Fertilizers and liming materials” (Secretariat: DIN, Germany) under the mandate M/335. The responsible German body involved in its preparation was the Normenausschuss Lebensmittel und landwirtschaftliche Produkte (Food and Agricultural Products Standards Committee), Work

5、ing Committee NA 057-03-02 AA Dngemittel. The method specified in this standard is based upon Regulation (EC) No 2003/2003 relating to fertilizers, Annex IV, method 3.2 (see Bibliography). DIN EN 15959 supersedes DIN SPEC 1172 (DIN CEN/TS 15959):2010-03, which has been adopted by CEN/TC 260 as a Eur

6、opean Standard based on the results of the unique acceptance procedure (UAP). Amendments This standard differs from DIN SPEC 1172 (DIN CEN/TS 15959):2010-03 as follows: a) the prestandard status has been changed to that of a full standard; b) the standard has been editorially revised. Previous editi

7、ons DIN SPEC 1172 (DIN CEN/TS 15959):2010-03 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15959 November 2011 ICS 65.080 Supersedes CEN/TS 15959:2009English Version Fertilizers - Determination of extracted phosphorus Engrais - Dosage du phosphore extrait Dngemittel - Bestimmung von Phosphor

8、in den ExtraktenThis European Standard was approved by CEN on 15 October 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 bib

9、liographical 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 respo

10、nsibility of 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, Gr

11、eece, Hungary, 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 Manage

12、ment Centre: 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 15959:2011: EEN 15959:2011 (E) 2 Contents Page Foreword 31 Scope 42 Normative references 43 Terms and definitions .44 Principle 45

13、Sampling and sample preparation .46 Reagents .47 Apparatus .58 Procedure .68.1 Treatment of the solution 68.2 Hydrolysis .68.3 Weighing the crucible .68.4 Precipitation .68.5 Filtering and washing 78.6 Drying and weighing .78.7 Blank test 78.8 Verification .79 Calculation and expression of the resul

14、t 710 Precision .810.1 Inter-laboratory tests .810.2 Repeatability .810.3 Reproducibility .811 Test report 9Annex A (informative) Statistical results of the inter-laboratory test . 10Bibliography . 12DIN EN 15959:2012-02 EN 15959:2011 (E) 3 Foreword This document (EN 15959:2011) has been prepared by

15、 Technical Committee CEN/TC 260 “Fertilizers and liming materials”, the secretariat of which is held by DIN. 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 May 2012, and conflicting national stan

16、dards shall be withdrawn at the latest by May 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes CEN/TS 15

17、959:2009. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. The following has been added to the former edition of the European Standard: a) the CEN Technical Specification has been adopted as a European Standard; b) edito

18、rial revision. 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, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, I

19、celand, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. DIN EN 15959:2012-02 EN 15959:2011 (E) 4 1 Scope This European Standard specifies a method for the determination of pho

20、sphorus in fertilizer extracts. The method is applicable to all extracts of fertilizers for the determination of the different forms of phosphorus as phosphorus soluble in mineral acids, water soluble phosphorus, phosphorus soluble in solutions of ammonium citrate, phosphorus soluble in 2 % citric a

21、cid and phosphorus soluble in 2 % formic acid. 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 document (including any

22、amendments) applies. EN 1482-2, Fertilizers and liming materials Sampling and sample preparation Part 2: Sample preparation EN 12944-1:1999, Fertilizers and liming materials and soil improvers Vocabulary Part 1: General terms EN 12944-2:1999, Fertilizers and liming materials and soil improvers Vocab

23、ulary Part 2: Terms relating to fertilizers 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 12944-1:1999 and EN 12944-2:1999 apply. 4 Principle After possible hydrolysis, phosphorus is precipitated in an acid media in the form of quinoline phosphomoly

24、bdate. After filtering and washing, the precipitate is dried at 250 C and weighed. In the above mentioned conditions no interfering action is exerted by the compounds likely to be found in the solution (mineral and organic acids, ammonium ions, soluble silicates, etc.) if a reagent based on sodium m

25、olybdate or ammonium molybdate is used in the precipitation. 5 Sampling and sample preparation Sampling is not part of the method specified in this document. A recommended sampling method is given in EN 1482-1. Sample preparation shall be carried out in accordance with EN 1482-2. Grinding of the lab

26、oratory sample is recommended for homogeneity reasons. 6 Reagents 6.1 Water, distilled or demineralized. DIN EN 15959:2012-02 EN 15959:2011 (E) 5 6.2 Concentrated nitric acid, = 1,40 g/ml. 6.3 Preparation of reagents 6.3.1 Preparation of the reagent based on sodium molybdate Solution A: Dissolve 70

27、g of sodium molybdate dihydrate in 100 ml of distilled water. Solution B: Dissolve 60 g of citric acid monohydrate in 100 ml of distilled water and add 85 ml concentrated nitric acid (6.2). Solution C: Stir solution A into solution B to obtain solution C. Solution D: To 50 ml of distilled water, add

28、 35 ml of concentrated nitric acid (6.2), then 5 ml of freshly distilled quinoline. Add this solution to solution C, mix thoroughly and leave standing overnight in the dark. After this make up to 500 ml with distilled water, mix again, and filter through a sintered glass funnel (7.7). 6.3.2 Preparat

29、ion of the reagent based on ammonium molybdate Solution A: In 300 ml of distilled water, dissolve 100 g of ammonium molybdate while heating gently and stirring from time to time. Solution B: Dissolve 120 g of citric acid monohydrate in 200 ml of distilled water, add 170 ml of concentrated nitric aci

30、d (6.2). Solution C: Add 10 ml of freshly distilled quinoline to 70 ml of concentrated nitric acid (6.2). Solution D: Slowly pour, stirring well, solution A into solution B. After thoroughly mixing add solution C to this mixture and make up to 1 l. Leave standing for two days in a dark place and fil

31、ter through a sintered glass funnel (7.7). The reagents 6.3.1 and 6.3.2 may be used in the same way; both shall be kept in the dark in stoppered polyethylene bottles. 7 Apparatus 7.1 Standard laboratory equipment. 7.2 500 ml Erlenmeyer flask, with a wide neck. 7.3 Graduated pipettes, of 10 ml, 25 ml

32、 and 50 ml. 7.4 Filter crucible, with porosity of 5 m to 20 m. 7.5 Buchner flask. 7.6 Drying oven, regulated at (250 10) C. 7.7 Sintered glass funnel, with porosity of 5 m to 20 m. DIN EN 15959:2012-02 EN 15959:2011 (E) 6 8 Procedure 8.1 Treatment of the solution With a pipette (7.3), take an aliquo

33、t part of fertilizer extract (see Table 1) containing about 0,01 g of P2O5 and place it in the Erlenmeyer flask (7.2). Add 15 ml of concentrated nitric acid (6.2) and dilute with water to about 100 ml. When the solution to be precipitated contains more than 15 ml of citrate solution (neutral citrate

34、, Petermann or Joulie alkaline citrate), an amount of 21 ml of concentrated nitric acid (6.2) shall be added. Table 1 Determination of the aliquot parts of the phosphate solutions % P2O5in the fertilizer % P in the fertilizer Sample for analysis g Dilution to ml Sample ml Dilution to ml Sample to be

35、 precipitatedml Quinoline phospho-molybdate conversion factor (F), in % P2O5Quinoline phospho-molybdate conversion factor (F), in % P 5 to 10 2,2 to 4,4 1 5 500 500 - - - - 50 10 32,074 32,074 13,984 13,984 10 to 25 4,4 to 11,0 1 5 500 500 - 50 - 500 25 50 64,148 64,148 27,968 27,968 25 11 1 5 500 5

36、00 - 50 - 500 10 25 160,370 128,296 69,921 55,937 8.2 Hydrolysis If the presence of metaphosphates, pyrophosphates or polyphosphates is suspected in the solution, carry out the hydrolysis as follows. Bring the content of the Erlenmeyer flask (7.2) to the boil slowly and keep at this temperature unti

37、l hydrolysis is completed. This usually takes 1 h. Care shall be taken to avoid losses by splashing and excessive evaporation which could reduce the initial volume by more than half, by fitting a reflux condenser. After hydrolysis make up to the initial volume with water (6.1). 8.3 Weighing the cruc

38、ible Dry the filter crucible (7.4) for at least 15 min in the drying oven (7.6) set at (250 10) C. Cool in a desiccator and weigh. 8.4 Precipitation Heat the acid solution contained in the Erlenmeyer flask (7.2) until it begins to boil. Then start the precipitation of the quinoline phosphomolybdate

39、by adding 40 ml of the precipitating reagent (6.3.1 or 6.3.2) drop by drop, stirring continuously. To precipitate phosphate solutions containing more than 15 ml of citrate solution (neutral citrate, Petermann or Joulie) which have been acidified with 21 ml of concentrated nitric acid (see 8.1), an a

40、mount of 80 ml of the precipitating reagent shall be used. Place the Erlenmeyer flask in a steam bath, leave it there for 15 min, shaking it from time to time. The solution may be filtered immediately or after it has cooled down. DIN EN 15959:2012-02 EN 15959:2011 (E) 7 8.5 Filtering and washing Fil

41、ter the solution under vacuum by decantation. Wash the precipitate in the Erlenmeyer flask (7.2) with 30 ml of water (6.1). Decant and filter the solution. Repeat this process five times. Quantitatively transfer the rest of the precipitate into the crucible washing it with water. Wash four times wit

42、h 20 ml of water, allowing the liquid to drain from the crucible before each addition. Dry the precipitate thoroughly. 8.6 Drying and weighing Wipe the outside of the crucible with a filter paper. Place this crucible in a drying oven (7.6) and keep it there until its mass remains constant, at a temp

43、erature of 250 C (usually 15 min); leave it to cool in the desiccator at ambient temperature and weigh rapidly. 8.7 Blank test For each series of determinations, carry out a blank test using only the reagents and solvents in the proportions used in the extraction (citrate solution, etc.) and allow f

44、or them in the calculation of the final result. 8.8 Verification Carry out the determination using an aliquot part of a potassium dihydrogen phosphate solution containing 0,01 g of P2O5. 9 Calculation and expression of the result If the samples for analysis and dilutions are used according to Table

45、1, calculate the mass fraction, wP, in percent according to Equation (1): )(21PFmmw = (1) If the samples for analysis and dilutions are used according to Table 1, calculate the mass fraction, 52OPw , in percent according to Equation (2): Fmmw = )(21OP52(2) where m1 is the mass, in grams, of the quin

46、oline phosphomolybdate; m2is the mass, in grams, of the quinoline phosphomolybdate obtained in the blank test; F and F are factors given in the last two columns of Table 1. If the samples for analysis and dilutions differ from those of Table 1, calculate the mass fraction, wP, in percent according t

47、o Equation (3): MDfmmw100)(21P=(3) If the samples for analysis and dilutions differ from those of Table 1, calculate the mass fraction, 52OPw , in percent according to Equation (4): MDfmmw100)(21OP52=(4) DIN EN 15959:2012-02 EN 15959:2011 (E) 8 where m1is the mass, in grams, of the quinoline phospho

48、molybdate; m2is the mass, in grams, of the quinoline phosphomolybdate obtained in the blank test; f and f are factors of quinoline phosphomolybdate into P2O5= 0,032 074, (f) or into P = 0,013 984 (f); D is the dilution factor; M is the mass, in grams, of the test portion analyzed. 10 Precision 10.1 Inter-laboratory tests Inter-laboratory tests have been carried out in 2008 based on extraction methods according