DIN EN 15475-2009 Fertilizers - Determination of ammoniacal nitrogen English version of DIN EN 15475 2009-04《肥料 氨态氮的测定》.pdf

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1、April 2009DEUTSCHE NORM English price group 10No 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 65.080!$W$A“1520130www.d

2、in.deDDIN EN 15475Fertilizers Determination of ammoniacal nitrogenEnglish version of DIN EN 15475:2009-04Dngemittel Bestimmung von AmmoniumstickstoffEnglische Fassung DIN EN 15475:2009-04SupersedesDIN CEN/TS 15475:2006-12www.beuth.deDocument comprises 17 pagesDIN EN 15475:2009-04 2 National foreword

3、 This standard has been prepared by Technical 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 Agricultu

4、ral Products Standards Committee), Technical Committee NA 057-03-02 AA Dngemittel. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 5725-1 DIN ISO 5725-1 Amendments This standard differs from DIN CEN/TS 15475:2006-12 as follows: a) Fertiliz

5、ers containing urea, cyanamide or other organic nitrogenous compounds have been deleted from the scope. b) In Table 3, F-value 0,75 has been changed to 0,175 and F-value 1,00 to 1,400. c) In Table 3, the approximate maximum quantity of nitrogen to be distilled has been changed from 150 mg to 200 mg.

6、 d) Normative references have been updated. e) The standard has been editorially revised. Previous editions DIN CEN/TS 15475: 2006-12 National Annex NA (informative) Bibliography DIN ISO 5725-1, Accuracy (trueness and precision) of measurement methods and results Part 1: General principles and defin

7、itions EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 15475January 2009ICS 65.080 Supersedes CEN/TS 15475:2006 English VersionFertilizers - Determination of ammoniacal nitrogenEngrais - Dtermination de lazote ammoniacal Dngemittel - Bestimmung von AmmoniumstickstoffThis European Standard was appr

8、oved by CEN on 30 November 2008.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 references concerning such national

9、standards 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 its own language and notifie

10、d 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, Lithuania, Luxembourg, Malta, N

11、etherlands, 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 2009 CEN All rights of exploitation

12、 in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15475:2009: EEN 15475:2009 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle 4 5 Reagents .4 6 Apparatus .5 7 Sampling and sample preparation 10 8 Procedure 10

13、9 Calculation and expression of the result . 12 10 Precision 12 11 Test report . 13 Annex A (informative) Results of the inter-laboratory tests 14 Bibliography . 15 DIN EN 15475:2009-04 EN 15475:2009 (E) 3 Foreword This document (EN 15475:2009) has been prepared by Technical Committee CEN/TC 260 “Fe

14、rtilizers 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 July 2009, and conflicting national standards shall be withdrawn at the la

15、test by July 2009. 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 15475:2006. This document has been

16、prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. 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, Cypr

17、us, 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 the United Kingdom. DIN EN 15475:2009-04 EN 15475:2009 (E

18、) 4 1 Scope This European Standard specifies a method for the determination of the ammoniacal nitrogen content in fertilizers. The method is applicable to all nitrogenous fertilizers including compound fertilizers, in which nitrogen is found exclusively either in the form of ammonium salts or ammoni

19、um salts together with nitrates. This European Standard is not applicable to fertilizers containing urea, cyanamide or other organic nitrogenous compounds. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the

20、 edition cited applies. For undated references, the latest edition of the referenced document (including any 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 improver

21、s Vocabulary Part 1: General terms EN 12944-2:1999, Fertilizers and liming materials and soil improvers Vocabulary Part 2: Terms relating to fertilizers EN ISO 3696:1995, Water for analytical laboratory use Specification and test methods (ISO 3696:1987) 3 Terms and definitions For the purposes of th

22、is document, the terms and definitions given in EN 12944-1:1999 and EN 12944-2:1999 apply. 4 Principle Displacement of ammonia by means of an excess of sodium hydroxide, distillation and determining the yield of ammonia in a given volume of a standard sulfuric acid and titration of the excess acid b

23、y means of a standard solution of sodium or potassium hydroxide. 5 Reagents 5.1 General Use only reagents of recognized analytical grade and distilled or demineralized water, free from carbon dioxide and all nitrogenous compounds (grade 3 according to EN ISO 3696:1995). DIN EN 15475:2009-04 EN 15475

24、:2009 (E) 5 5.2 Diluted hydrochloric acid, mix one volume of (HCl) = 1,18 g/ml with one volume of water. 5.3 Sulfuric acid (for variant a), c = 0,05 mol/l. 5.4 Sodium or potassium hydroxide solution (for variant a), carbonate free, c = 0,1 mol/l. 5.5 Sulfuric acid (for variant b, see NOTE in 8.2), c

25、 = 0,1 mol/l. 5.6 Sodium or potassium hydroxide solution (for variant b, see NOTE in 8.2), carbonate free, c = 0,2 mol/l. 5.7 Sulfuric acid (for variant c, see NOTE in 8.2), c = 0,25 mol/l. 5.8 Sodium or potassium hydroxide solution (for variant c, see NOTE in 8.2), carbonate free, c = 0,5 mol/l. 5.

26、9 Sodium hydroxide, 30 %, of approximately (NaOH) = 1,33 g/ml, ammonia free. 5.10 Indicator solutions 5.10.1 Mixed indicator Solution A: Dissolve 1 g of methyl red in 37 ml of sodium hydroxide solution c = 0,1 mol/l and make up to 1 l with water. Solution B: Dissolve 1 g of methylene blue in water a

27、nd make up to 1 l. Mix one volume of A with two volumes of B. This indicator is violet in acid solution, grey in neutral solution and green in alkaline solution. Use 0,5 ml (10 drops) of this indicator solution. 5.10.2 Methyl red indicator solution Dissolve 0,1 g of methyl red in 50 ml of 95 % ethan

28、ol. Make up to 100 ml with water and filter if necessary. This indicator may be used (4 to 5 drops) instead of the preceding one. This indicator is red in acid solution and yellow in alkaline solution. 5.11 Anti-bump granules (i. e. pumice stone, glass pearls), washed in hydrochloric acid and calcin

29、ed. 5.12 Ammonium sulfate, p. a. 6 Apparatus 6.1 Distillation apparatus Consisting of a round-bottomed flask of suitable capacity connected to a condenser by means of a splash head. The equipment is made of borosilicate glass. NOTE The different types of equipment recommended for this determination

30、are reproduced, showing all the features of construction in Figures 1, 2, 3 and 4. DIN EN 15475:2009-04 EN 15475:2009 (E) 6 An automatic distillation apparatus may also be used, provided that the results are statistically equivalent. Dimensions in millimetres Key 1 round-bottomed, long-necked flask

31、of 1 000 ml capacity 2 distillation tube with a splash head, connected to the condenser by means of a spherical joint (No 18) (the spherical joint for the connection to the condenser may be replaced by an appropriate rubber connection) 3 funnel with a polytetrafluoroethylene (PTFE) tap (6) for the a

32、ddition of sodium hydroxide 4 six-bulb condenser with spherical joint (No 18) at the entrance, and joined at the issue to a glass extension tube by means of a small rubber connection (when the connection to the distillation tube is effected by means of a rubber tube, the spherical joint may be repla

33、ced by a suitable rubber bung) 5 500-ml-flask in which the distillate is collected 6 PTFE-tap (the tap may likewise be replaced by a rubber connection with a clip) Figure 1 Distillation apparatus 1 DIN EN 15475:2009-04 EN 15475:2009 (E) 7 Dimensions in millimetres Key 1 round-bottomed, short-necked

34、flask of 1 000 ml capacity with a spherical joint (No 35) 2 distillation tube with a splash head, equipped with a spherical joint (No 35) at the entrance and a spherical joint (No 18) at the issue, connected at the side to a funnel with a polytetrafluoroethylene (PTFE) tap (5) for the addition of so

35、dium hydroxide 3 six-bulb condenser with a spherical joint (No 18) at the entrance and joined at the issue to a glass extension tube by means of a small rubber connection 4 500-ml-flask in which the distillate is collected 5 PTFE-tap a enlarged description Figure 2 Distillation apparatus 2 DIN EN 15

36、475:2009-04 EN 15475:2009 (E) 8 Dimensions in millimetres Key 1 round-bottomed, long-necked flask of 750 ml or 1 000 ml capacity with, a bell mouth 2 distillation tube with a splash head and a spherical joint (No 18) at the issue 3 elbow tube with a spherical joint (No 18) at the entrance, and a dri

37、p cone (the connection to the distillation tube may be effected by means of a rubber tube instead of a spherical joint) 4 six-bulb condenser joined at the issue to a glass extension tube by means of a small rubber connection 5 500-ml-flask in which the distillate is collected Figure 3 Distillation a

38、pparatus 3 DIN EN 15475:2009-04 EN 15475:2009 (E) 9 Dimensions in millimetres Key 1 round-bottomed, long-necked flask of 1 000 ml capacity with a bell mouth 2 distillation tube with a splash head and a spherical joint (No 18), at the issue, connected at the side to a funnel with a polytetrafluoroeth

39、ylene (PTFE) tap (5) for the addition of sodium hydroxide (a suitable rubber bung may be used instead of the spherical joint; the tap may be replaced by a rubber connection with an appropriate clip) 3 six-bulb condenser with a spherical joint (No 18) at the entrance, joined at the issue, by a rubber

40、 connection, to a glass extension tube (when the connection to the distillation tube is effected by means of a rubber tube, the spherical joint may be replaced by a suitable rubber bung) 4 500-ml-flask for the collection of the distillate 5 PTFE-tap Figure 4 Distillation apparatus 4 DIN EN 15475:200

41、9-04 EN 15475:2009 (E) 10 6.2 Pipettes, capacity of 10 ml, 20 ml, 25 ml, 50 ml, 100 ml and 200 ml. 6.3 Graduated flasks, capacity 500 ml. 6.4 Rotary shaker, 35 to 40 revolutions per minute. 7 Sampling and sample preparation Sampling is not part of the method specified in this document. A recommended

42、 sampling method is given in EN 1482-1. Sample preparation shall be carried out in accordance with EN 1482-2. 8 Procedure 8.1 Preparation of the solution According to Table 1, Table 2 or Table 3, depending on the variant chosen, weigh to the nearest 0,001 g a quantity of 5 g, 7 g, or 10 g of the pre

43、pared sample and transfer it into a 500-ml flask. Add 50 ml of water and then 20 ml of hydrochloric acid (5.2). Shake. Leave undisturbed until the evolution of carbon dioxide has ceased. Add 200 ml of water and shake for half an hour with the rotary shaker (6.4). Filter through a filter into a 500-m

44、l graduated flask and make up to the volume with water. 8.2 Analysis of the solution According to the variant chosen, place in the receiving flask a measured quantity of standard sulfuric acid as indicated in Table 1, Table 2 or Table 3. Add the appropriate quantity of the chosen indicator solution

45、(5.10.1 or 5.10.2) and, if necessary, water in order to obtain a volume of at least 50 ml. The end of the extension tube of the condenser shall be below the surface of the solution. Transfer by precision pipette, according to the details given in Table 1, an aliquot portionof the clear solution, int

46、o the distillation flask of the apparatus. Add water in order to obtain a total volume of about 350 ml, and several grains of pumice in order to control the boiling. Assemble the distillation apparatus and taking care to avoid any loss of ammonia, add to the contents of the distillation flask 10 ml

47、of concentrated sodium hydroxide solution (5.9) or 20 ml of the sodium hydroxide solution (5.9) in the cases where one has used 20 ml hydrochloric acid (5.2) in order to dissolve the test sample. Gradually warm the flask; avoid boiling vigorously. When boiling commences, distil at a rate of about 10

48、0 ml in 10 min to 15 min; the total volume of distillate should be about 250 ml. The condenser shall be regulated so that a continuous flow of condensate is ensured. The distillation should be completed in 30 min to 40 min. When no more ammonia is likely to be evolved, lower the receiving flask so t

49、hat the tip of the condenser extension is above the surface of the liquid. Test the subsequent distillate by means of an appropriate reagent to ensure that all the ammonia is completely distilled. Wash the condenser extension with a little water and titrate the surplus acid with the standard solution of sodium or potassium hydroxide prescribed for the variant adopted (see NOTE). NOTE Standard solutions of different strengths may be used for the back titration provided that the volumes used for the titration do not, as far as possible, exceed 40