1、BS EN 15604:2009ICS 65.080NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDFertilizers Determination ofdifferent forms ofnitrogen in the samesample, containingnitrogen as nitric,ammoniacal, urea andcyanamide nitrogenThis British Standardwas published under theaut
2、hority of the StandardsPolicy and StrategyCommittee on 30 June 2009 BSI 2009ISBN 978 0 580 62391 2Amendments/corrigenda issued since publicationDate CommentsBS EN 15604:2009National forewordThis British Standard is the UK implementation of EN 15604:2009. Itsupersedes DD CEN/TS 15604:2007 which is wi
3、thdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/37, Fertilisers and related chemicals.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a
4、 contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS EN 15604:2009EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 15604January 2009ICS 65.080 Supersedes CEN/TS 15604:2007 English VersionFertilizers - Determi
5、nation of different forms of nitrogen in thesame sample, containing nitrogen as nitric, ammoniacal, ureaand cyanamide nitrogenEngrais - Dtermination des diffrentes formes dazotedans un mme chantillon contenant lazote sous formenitrique, ammoniacale, urique et cyanamidiqueDngemittel - Bestimmung vers
6、chiedener, nebeneinanderanwesender Stickstoff-Formen in derselben Probe mitStickstoff in Form von Ammonium, Nitrat, Harnstoff undCyanamidThis 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 conditi
7、ons for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three off
8、icial versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its 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,
9、Belgium, Bulgaria, Cyprus, 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.EUROPEAN COMMITTEE FO
10、R STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2009 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15604:2009: EBS EN 15604:2009EN 15604:2009 (E) 2
11、 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle 4 5 Reagents .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 BS EN 15604:2009EN 15604:2009 (E) 3 Foreword
12、This document (EN 15604:2009) has been prepared by 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
13、 latest by July 2009, and conflicting national standards shall be withdrawn at the latest 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 su
14、ch patent rights. This document supersedes CEN/TS 15604:2007. This document has been 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 coun
15、tries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spa
16、in, Sweden, Switzerland and the United Kingdom. BS EN 15604:2009EN 15604:2009 (E) 4 1 Scope This European 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 Regulat
17、ion (EC) No 2003/2003 1 containing nitrogen in various forms. 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
18、(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 improvers Vocabulary Part 1: General terms EN 12944-2:1999, Fertilizers and liming materials and soil
19、improvers Vocabulary Part 2: Terms relating to fertilizers EN 15475, Fertilizers Determination of ammoniacal 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
20、 For the purposes of this document, the terms and definitions given in EN 12944-1:1999 and EN 12944-2:1999 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
21、cyanamide. In the absence of nitrates, the test sample is mineralized by direct Kjeldahl digestion. In 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 accordin
22、g to EN 15475. NOTE If analysis shows an insoluble nitrogen content of more than 0,5 %, one concludes that the fertilizer contains other forms of insoluble nitrogen not included in the list in 1, Annex I. BS EN 15604:2009EN 15604:2009 (E) 5 4.2 Forms of soluble nitrogen 4.2.1 General The forms of so
23、luble nitrogen referred to in 4.2.2 to 4.2.7 are determined from different aliquots taken from the 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
24、EN 15475). 4.2.2.2 In the presence of nitrates, by Kjeldahl digestion on an aliquot part taken from 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
25、By Kjeldahl digestion after elimination in an acid medium of nitrate nitrogen with ferrous sulfate. 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 betwe
26、en the nitrogen determined as summarized in 4.2.2.2 and that determined as summarized in 4.2.3 or 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
27、the nitrogen determined as summarized in 4.2.2.2 and that determined as summarized in 4.2.3 or between 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 nitrog
28、en and ammoniacal plus nitrate nitrogen, according to EN 15475. 4.2.5.2 In the presence of urea nitrogen 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 nit
29、rogen 4.2.6.1 By conversion using urease, into ammonia which is titrated with a standard solution 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
30、 compound fertilizers. or 4.2.6.3 By difference according to Table 1. BS EN 15604:2009EN 15604:2009 (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 Presen
31、t 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) (4.2.2.1) (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 reagent
32、s of recognized analytical grade and distilled or de-mineralized water of grade 3 according 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,
33、p.a. 5.5 Potassium nitrate, p.a. 5.6 Ammonium sulfate, p.a. 5.7 Urea, p.a. 5.8 Diluted sulfuric 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
34、concentration), free from ammonia. 5.11 Standard solution of sodium or potassium hydroxide, c = 0,2 mol/l, free from carbonates. BS EN 15604:2009EN 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
35、 1 l with water. The solution shall be perfectly clear and prepared immediately before 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 Rochel
36、le salt (potassium sodium tartrate), then a sufficient quantity of sodium bicarbonate for 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 correspon
37、ds to 0,01128 g of SnCl2.2H2O. At least 80 % of the total tin present in the solution thus 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
38、 of hydrochloric acid (20= 1,18 g/ml) with one volume of water. 5.15 Acetic acid, 96 % 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.
39、20 Saturated solution of potassium carbonate 5.21 Standard solution of sodium or potassium 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 sol
40、ution of hydrochloric acid, c = 0,1 mol/l. 5.26 Urease solution Suspend 0,5 g of active 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. BS EN 15604:2009EN 15604:2009 (E) 8 5.27 Xanthydrol Use a solution at 5 % in ethanol or methanol
41、(5.32) (do not use products giving a high proportion of insoluble matter). The solution 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
42、to 1,25 g per determination. 5.29 Anti-bump granules, washed in hydrochloric acid 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 wat
43、er and make up to 1 l. 5.30.3 Combined indicator solution Mix one volume of solution 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 sol
44、ution Dissolve 0,1 g of methyl red in 50 ml of 95 % ethanol. Make up to 100 ml with 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
45、 Ethanol or methanol, solution 95 %. 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 determinat
46、ion are reproduced, showing all the features of construction, in Figures 1, 2, 3 and 4. An automatic distillation apparatus may also be used, provided that the results are statistically equivalent. BS EN 15604:2009EN 15604:2009 (E) 9 Dimensions in millimetres Key 1 round-bottomed, long-necked flask
47、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
48、ddition of sodium hydroxide (the tap may likewise be replaced by a rubber connection with a clip) 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 i
49、s effected by means of a rubber tube, the spherical joint may be replaced by a suitable rubber bung) 5 500 ml flask in which the distillate is collected 6 PTFE tap ahole Figure 1 Distillation apparatus 1 BS EN 15604:2009EN 15604:2009 (E) 10 Dimensions in millimetres Key 1 round-bottomed, short-necked 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 wi