DIN EN 15604-2009 Fertilizers - Determination of different forms of nitrogen in the same sample containing nitrogen as nitric ammoniacal urea and cyanamide nitrogen English version.pdf

1、June 2009DEUTSCHE NORM English price group 13No 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!$WS“1529348www.din

2、.deDDIN EN 15604Fertilizers Determination of different forms of nitrogen in the same sample,containing nitrogen as nitric, ammoniacal, urea and cyanamide nitrogenEnglish version of DIN EN 15604:2009-06Dngemittel Bestimmung verschiedener, nebeneinander anwesender Stickstoff-Formen in derselbenProbe m

3、it Stickstoff in Form von Ammonium, Nitrat, Harnstoff und CyanamidEnglische Fassung DIN EN 15604:2009-06SupersedesDIN CEN/TS 15604:2008-04www.beuth.deDocument comprises pages24DIN EN 15604:2009-06 2 National foreword This standard has been prepared by Technical Committee CEN/TC 260 “Fertilizers and

4、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), Technical Committee NA 057-03-02 AA Dngemittel. T

5、he method specified in this standard is based upon Regulation (EC) No 2003/2003 relating to fertilizers, Annex IV, method 2.6.1. Amendments This standard differs from DIN CEN/TS 15604:2008-04 as follows: a) In subclause 5.12, the iodine solution has been corrected to read 0,05 mol/l (instead of 0,1

6、mol/l). b) Information on the determination of the various soluble forms of nitrogen formerly given in subclauses 8.2.1.2 and 8.2.1.3 is now included in subclause 8.2. c) The standard has been brought in line with the current rules of presentation. d) The normative references have been updated. Prev

7、ious editions DIN CEN/TS 15604: 2008-04 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15604 January 2009 ICS 65.080 Supersedes CEN/TS 15604:2007English Version Fertilizers Determination of different forms of nitrogen in the same sample, containing nitrogen as nitric, ammoniacal, urea and cyan

8、amide nitrogen Engrais Dtermination des diffrentes formes dazote dans un mme chantillon contenant lazote sous forme nitrique, ammoniacale, urique et cyanamidique Dngemittel Bestimmung verschiedener, nebeneinander anwesender Stickstoff-Formen in derselben Probe mit Stickstoff in Form von Ammonium, Ni

9、trat, Harnstoff und Cyanamid This European Standard was approved by CEN on 6 December 2008. 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

10、lists and bibliographical references concerning such national 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 r

11、esponsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary,

12、 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 Management Centre: ru

13、e de Stassart, 36 B-1050 Brussels 2009 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15604:2009: EEN 15604:2009 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle 4 5 Reagents

14、 .6 6 Apparatus .8 7 Sampling and sample preparation 13 8 Procedure 14 9 Verification of the result . 21 10 Test report . 21 Bibliography . 22 DIN EN 15604:2009-06 EN 15604:2009 (E) 3 Foreword This document (EN 15604:2009) has been prepared by Technical Committee CEN/TC 260 “Fertilizers and liming m

15、aterials”, 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 latest by July 2009. Att

16、ention 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 15604:2007. This document has been prepared under a manda

17、te 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, Cyprus, Czech Republic, De

18、nmark, 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 15604:2009-06 EN 15604:2009 (E) 4 1 Scope This Europ

19、ean Standard specifies a method for the determination of any one form of nitrogen in the presence of any other form. The method is applicable to any fertilizer provided for in Annex I of the Regulation (EC) No 2003/2003 1 containing nitrogen in various forms. 2 Normative references The following ref

20、erenced 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 amendments) applies. EN 1482-2, Fertilizers and liming materials Sampling and sample pr

21、eparation 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 Vocabulary Part 2: Terms relating to fertilizers EN 15475, Fertilizers Determination of ammo

22、niacal nitrogen EN 15562, Fertilizers Determination of cyanamide nitrogen EN ISO 3696:1995, Water for analytical laboratory use Specification and test methods (ISO 3696:1987) 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 12944-1:1999 and EN 12944-2:

23、1999 apply. 4 Principle 4.1 Total soluble and insoluble nitrogen According to the list of standard fertilizers given in Annex I of 1, this determination is applicable to products containing calcium cyanamide. In the absence of nitrates, the test sample is mineralized by direct Kjeldahl digestion. In

24、 the presence of nitrates, the test sample is mineralized by Kjeldahl digestion after reduction with the aid of metallic iron and stannous chloride. In both cases, the ammonia is determined according to EN 15475. NOTE If analysis shows an insoluble nitrogen content of more than 0,5 %, one concludes

25、that the fertilizer contains other forms of insoluble nitrogen not included in the list in 1, Annex I. DIN EN 15604:2009-06 EN 15604:2009 (E) 5 4.2 Forms of soluble nitrogen 4.2.1 General The forms of soluble nitrogen referred to in 4.2.2 to 4.2.7 are determined from different aliquots taken from th

26、e same solution of the test sample: 4.2.2 Total soluble nitrogen 4.2.2.1 In the absence of nitrates, by direct Kjeldahl digestion. The ammonia is then determined (by the same method as that described in EN 15475). 4.2.2.2 In the presence of nitrates, by Kjeldahl digestion on an aliquot part taken fr

27、om the solution after reduction according to Ulsch. The ammonia is then determined (by the same method as that described in EN 15475). 4.2.3 Total soluble nitrogen with the exception of nitrate nitrogen By Kjeldahl digestion after elimination in an acid medium of nitrate nitrogen with ferrous sulfat

28、e. The ammonia is then determined (by the same method as that described in EN 15475). 4.2.4 Nitrate nitrogen by difference 4.2.4.1 In the absence of calcium cyanamide, by determining the difference between the nitrogen determined as summarized in 4.2.2.2 and that determined as summarized in 4.2.3 or

29、 between total soluble nitrogen (4.2.2) and the sum of ammoniacal nitrogen and ureic organic nitrogen (4.2.5 + 4.2.6). 4.2.4.2 In the presence of calcium cyanamide, by determining the difference between the nitrogen determined as summarized in 4.2.2.2 and that determined as summarized in 4.2.3 or be

30、tween the nitrogen determined as summarized in 4.2.2.2 and the sum of that determined as summarized in 4.2.5 + 4.2.6 + 4.2.7. 4.2.5 Ammoniacal nitrogen 4.2.5.1 Solely in the presence of ammoniacal nitrogen and ammoniacal plus nitrate nitrogen, according to EN 15475. 4.2.5.2 In the presence of urea n

31、itrogen and/or cyanamide nitrogen by cold distillation after making slightly alkaline, the ammonia is absorbed in a standard solution of sulfuric acid and determined according to EN 15475. 4.2.6 Urea nitrogen 4.2.6.1 By conversion using urease, into ammonia which is titrated with a standard solution

32、 of hydrochloric acid. or 4.2.6.2 By gravimetry with xanthydrol: the co-precipitated biuret can be counted with urea nitrogen without great error, its content remaining generally low in absolute value in compound fertilizers. or 4.2.6.3 By difference according to Table 1. DIN EN 15604:2009-06 EN 156

33、04:2009 (E) 6 Table 1 Determination of urea nitrogen by difference Case Nitrate nitrogen Ammoniacal nitrogen Cyanamidic nitrogen Difference 1 2 3 4 Absent Present Absent Present Present Present Present Present Present Present Absent Absent (4.2.2.1) (4.2.5.2 + 4.2.7) (4.2.3) (4.2.5.2 + 4.2.7) (4.2.2

34、.1) (4.2.5.2) (4.2.3) (4.2.5.2) 4.2.7 Cyanamide nitrogen By precipitation as a silver compound, the nitrogen being determined in the precipitate by the Kjeldahl method. 5 Reagents 5.1 General Use only reagents of recognized analytical grade and distilled or de-mineralized water of grade 3 according

35、to EN ISO 3696:1995. 5.2 Potassium sulfate p.a. 5.3 Iron powder, reduced with hydrogen. The prescribed quantity of iron shall be able to reduce at least 50 m g of nitrate nitrogen. 5.4 Potassium thiocyanate, p.a. 5.5 Potassium nitrate, p.a. 5.6 Ammonium sulfate, p.a. 5.7 Urea, p.a. 5.8 Diluted sulfu

36、ric acid Dilute one volume of sulfuric acid (20 =1,84 g/ml) in one volume of water. 5.9 Standard solution of sulfuric acid, c = 0,1 mol/l. 5.10 Sodium hydroxide solution, aqueous solution of about 30 % (mass concentration), free from ammonia. 5.11 Standard solution of sodium or potassium hydroxide,

37、c = 0,2 mol/l, free from carbonates. DIN EN 15604:2009-06 EN 15604:2009 (E) 7 5.12 Stannous chloride solution Dissolve 120 g of SnCl2.2H2O in 400 ml of concentrated hydrochloric acid (20= 1,18 g/ml) and make up to 1 l with water. The solution shall be perfectly clear and prepared immediately before

38、use. It is essential to check the reducing power of stannous chloride: dissolve 0,5 g of SnCl2.2H2O in 2 ml of concentrated hydrochloric acid (20= 1,18 g/ml) and make up to 50 ml with water. Then add 5 g of Rochelle salt (potassium sodium tartrate), then a sufficient quantity of sodium bicarbonate f

39、or the solution to be alkaline to litmus paper. Titrate with an iodine solution (I2) of c = 0,05 mol/l in the presence of a starch solution as an indicator. 1 ml of iodine solution (I2) of c = 0,05 mol/l corresponds to 0,01128 g of SnCl2.2H2O. At least 80 % of the total tin present in the solution t

40、hus prepared shall be in bivalent form. For the titration at least 35 ml of the c = 0,05 mol/l iodine solution (I2) should be used. 5.13 Sulfuric acid, 20 = 1,84 g/ml. 5.14 Diluted hydrochloric acid Mix one volume of hydrochloric acid (20= 1,18 g/ml) with one volume of water. 5.15 Acetic acid, 96 %

41、to 100 %. 5.16 Sulfuric acid solution, containing about 30 % of H2SO4(mass concentration). 5.17 Ferrous sulfate, crystalline, FeSO4.7H2O. 5.18 Standard sulfuric acid solution, c = 0,05 mol/l. 5.19 Octyl alcohol 5.20 Saturated solution of potassium carbonate 5.21 Standard solution of sodium or potass

42、ium hydroxide, c = 0,1 mol/l (free from carbonates). 5.22 Saturated solution of barium hydroxide 5.23 Sodium carbonate solution, at 10 % (mass concentration). 5.24 Hydrochloric acid, c = 2 mol/l. 5.25 Standard solution of hydrochloric acid, c = 0,1 mol/l. 5.26 Urease solution Suspend 0,5 g of active

43、 urease in 100 ml of water. Using hydrochloric acid 0,1 mol/l (5.25), adjust the pH to 5,4, measured by a pH-meter. DIN EN 15604:2009-06 EN 15604:2009 (E) 8 5.27 Xanthydrol Use a solution at 5 % in ethanol or methanol (5.32) (do not use products giving a high proportion of insoluble matter). The sol

44、ution may be kept for three months in a well-stoppered bottle, away from the light. 5.28 Catalyst Use 0,3 g to 0,4 g of copper oxide per determination or an equivalent quantity of copper sulfate pentahydrate of 0,95 g to 1,25 g per determination. 5.29 Anti-bump granules, washed in hydrochloric acid

45、and calcined. 5.30 Indicator solutions 5.30.1 Solution A Dissolve 1 g of methyl red in 37 ml of sodium hydroxide solution 0,1 mol/l and make up to 1 l with water. 5.30.2 Solution B Dissolve 1 g of methylene blue in water and make up to 1 l. 5.30.3 Combined indicator solution Mix one volume of soluti

46、on A with two volumes of solution 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. 5.30.4 Methyl red indicator solution Dissolve 0,1 g of methyl red in 50 ml of 95 % ethanol. Make up to 100 ml wit

47、h water and filter if necessary. This indicator (four or five drops) may be used instead of that described in 5.30.3. 5.31 Indicator papers, Litmus bromothymol blue (or other papers sensitive to pH = 6 to pH = 8). 5.32 Ethanol or methanol, solution 95 %. 6 Apparatus 6.1 Distillation apparatus Consis

48、ting 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 are reproduced, showing all the features of construction, in Figures 1, 2, 3 a

49、nd 4. An automatic distillation apparatus may also be used, provided that the results are statistically equivalent. DIN EN 15604:2009-06 EN 15604:2009 (E) 9 Dimensions in millimetres Key 1 round-bottomed, long-necked flask 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 additi