DIN EN 16651-2015 Fertilizers - Determination of N-(n-Butyl)thiophosphoric acid triamide (NBPT) and N-(n-Propyl)thiophosphoric acid triamide (NPPT) - Method using high-performance .pdf

1、July 2015 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).ICS 65

2、.080!%D8“2332188www.din.deDDIN EN 16651Fertilizers Determination of N-(n-Butyl)thiophosphoric acid triamide (NBPT) andN-(n-Propyl)thiophosphoric acid triamide (NPPT) Method using high-performance liquid chromatography (HPLC);English version EN 16651:2015,English translation of DIN EN 16651:2015-07Dn

3、gemittel Bestimmung von N-(n-Butyl)thiophosphorsuretriamid (NBPT) undN-(n-Propyl)thiophosphorsuretriamid (NPPT) Verfahren mit Hochleistungs-Flssigchromatographie (HPLC);Englische Fassung EN 16651:2015,Englische bersetzung von DIN EN 16651:2015-07Engrais Dosage du N-(n-butyl)triamide de lacide thioph

4、osphorique (NBPT) et duN-(n-propyl)triamide de lacide thiophosphorique (NPPT) Mthode par chromatographie liquide haute performance (HPLC);Version anglaise EN 16651:2015,Traduction anglaise de DIN EN 16651:2015-07www.beuth.deDocument comprises 13 pagesIn case of doubt, the German-language original sh

5、all be considered authoritative.06.15DIN EN 16651:2015-07 2 A comma is used as the decimal marker. National foreword This document (EN 16651:2015) has been prepared by Technical Committee CEN/TC 260 “Fertilizers and liming materials” (Secretariat: DIN, Germany) The responsible German body involved i

6、n its preparation was the Normenausschuss Lebensmittel und landwirtschaftliche Produkte (Food and Agricultural Products Standards Committee), Working Committee NA 057-03-02 AA Dngemittel. The DIN Standard corresponding to the International Standard referred to in this document is as follows: ISO 572

7、5-2 DIN ISO 5725-2 National Annex NA (informative) Bibliography DIN ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method EUROPEAN STANDARD NORME EUROPENNE EURO

8、PISCHE NORM EN 16651 May 2015 ICS 65.080 English Version Fertilizers - Determination of N-(n-Butyl)thiophosphoric acid triamide (NBPT) and N-(n-Propyl)thiophosphoric acid triamide (NPPT) - Method using high-performance liquid chromatography (HPLC) Engrais - Dosage du N-(n-butyl)triamide de lacide th

9、iophosphorique (NBPT) et du N-(n-propyl)triamide de lacide thiophosphorique (NPPT) - Mthode par chromatographie liquide haute performance (HPLC) Dngemittel - Bestimmung von N-(n-Butyl)thiophosphorsuretriamid (NBPT) und N-(n-Propyl)thiophosphorsuretriamid (NPPT) - Verfahren mit Hochleistungs-Flssigch

10、romatographie (HPLC) This European Standard was approved by CEN on 16 April 2015. 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

11、bibliographical 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 re

12、sponsibility 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, Former Yugoslav

13、Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE N

14、ORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16651:2015 EEN 16651:2015 (E) 2 Contents Page Foreword 3 1 Scope 4 2

15、Normative references 4 3 Terms and definitions .4 4 Principle 4 5 Reagents .4 6 Apparatus .5 7 Sampling .6 8 Procedure .6 8.1 Preparation of the test solution 6 8.2 Calibration 6 8.3 Blank test 6 8.4 Calculation and expression of the results 6 8.4.1 Concentration of NBPT .6 8.4.2 Concentration of NP

16、PT .7 8.4.3 External response factors .7 8.4.4 Calculation of the total content 8 8.5 Environmental aspects .8 9 Precision .8 9.1 Inter-laboratory test .8 9.2 Repeatability .8 9.3 Reproducibility .8 10 Test report 9 Annex A (informative) Results of the inter-laboratory test 10 Bibliography . 11 DIN

17、EN 16651:2015-07 EN 16651:2015 (E) 3 Foreword This document (EN 16651:2015) 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

18、of an identical text or by endorsement, at the latest by November 2015, and conflicting national standards shall be withdrawn at the latest by November 2015. 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

19、 not be held responsible for identifying any or all such patent rights. 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 organisations of the foll

20、owing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands,

21、Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 16651:2015-07 EN 16651:2015 (E) 4 1 Scope This European Standard specifies a method for the quantitative determination of the urease inhibitors N-(n-Butyl)thiophosphoric acid tria

22、mide (NBPT, CAS-No. 94317-64-3) and N-(n-Propyl)thiophosphoric acid triamide (NPPT, CAS-No. 916809-14-8) content in urea based fertilizers using high-performance liquid chromatography (HPLC). 2 Normative references The following documents, in whole or in part, are normatively referenced in this docu

23、ment and are indispensable for its application. 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 preparation - Part 2: Samp

24、le 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 ISO 3696, Water for analytical laboratory use - Specif

25、ication and test methods (ISO 3696) 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 The fertilizer sample is diluted in water, grade 1. The concentration of N-(n-Butyl)thiophosphoric acid triamide (N

26、BPT) and N-(n-Propyl)thiophosphoric acid triamide (NPPT) is determined in diluted aqueous solution by high-performance liquid chromatography (HPLC) using an UV detector at 205 nm. 5 Reagents Use only reagents of recognized analytical grade. 5.1 Water, grade 1 according to EN ISO 3696. 5.2 Acetonitri

27、le, HPLC grade. 5.3 Urea, analytical pure. 5.4 NBPT, N-(n-Butyl)thiophosphoric acid triamide, CAS-No. 94317-64-3, analytical pure. 5.5 NPPT, N-(n-Propyl)thiophosphoric acid triamide, CAS-No. 916809-14-8, analytical pure. 5.6 Eluent. Mix in a 1 000 ml volumetric flask (6.2), 750 ml of water (5.1) and

28、 250 ml acetonitrile (5.2) and filter through a micro filter (6.3). 5.7 Stock solution, (NBPT) = 0,20 mg/ml and (NPPT) = 0,12 mg/ml. DIN EN 16651:2015-07 EN 16651:2015 (E) 5 Weigh in a 250 ml graduated flask (6.2), an amount of 50 mg NBPT and 30 mg NPPT. Add approximately 200 ml of water (5.1) and s

29、hake until NBPT and NPPT are diluted. Fill up to the mark with water (5.1) and shake. This stock solution may be used within 24 h. 5.8 Calibration solution C1, (NBPT) = 0,01 mg/ml and (NPPT) = 0,006 mg/ml. Fill into a 100 ml graduated flask (6.2), an amount of 5,00 ml stock solution (5.7). Fill up t

30、o the mark with water (5.1). This calibration solution may be used within 24 h. 5.9 Calibration solution C2, (NBPT) = 0,05 mg/ml and (NPPT) = 0,030 mg/ml. Fill into a 100 ml graduated flask an amount of 25,00 ml stock solution (5.7). Fill up to the mark with water (5.1). This calibration solution ma

31、y be used within 24 h. 5.10 Calibration solution C3, (NBPT) = 0,12 mg/ml and (NPPT) = 0,072 mg/ml. Fill into a 100 ml graduated flask an amount of 60,00 ml stock solution (5.7). Fill up to the mark with water (5.1). This calibration solution may be used within 24 h. 6 Apparatus 6.1 Analytical balanc

32、e, capable of weighing to an accuracy of 0,001 g. 6.2 Volumetric flasks, capacity 100 ml, 250 ml and 1 000 ml. 6.3 Micro filter, pore size 0,45 m. 6.4 One way shot, capacity 5 ml. 6.5 Vials, capacity 2 ml. 6.6 Appropriate shaking equipment. 6.7 HPLC apparatus, consisting of the following parts: 6.7.

33、1 HPLC instrument with UV-Detector, and optional an auto sampler and column oven. 6.7.2 HPLC separation column, e.g. LiChroSpher 100 RP-8 (250 mm 4 mm) 5 m or equivalent. The HPLC conditions based on this column are given in Table 1. DIN EN 16651:2015-07 EN 16651:2015 (E) 6 Table 1 Example of HPLC c

34、onditions aParameter Conditions Column LiChroSpher 100 RP-8 (250 mm 4 mm) 5 m Mobile phase Eluent (5.6) Flow rate 1,0 ml/min Injection volume 20 l UV detection at wavelength 205 nm Column temperature Room temperature Expected retention time NBPT approximately 7 min Expected retention time NPPT appro

35、ximately 5 min aThe use of an equivalent column could lead to different parameters. 7 Sampling Sampling from fertilizers, which are stored as bulk in storage buildings or warehouse or in packaged form is not part of the method specified in this document. A recommended sampling method is given in EN

36、1482-1. Sample preparation shall be carried out in accordance with EN 1482-2. 8 Procedure 8.1 Preparation of the test solution Weigh to the nearest 0,001 g an amount of 7,500 g of the test sample into a 250 ml volumetric flask and dissolve in 200 ml water (5.1), shake the flask with shaking equipmen

37、t (6.6) until the sample is completely dissolved. Fill up to the mark with water (5.1) and mix thoroughly. Fill the solution in a one way shot (6.4), filter through the micro filter (6.3) in a vial (6.5) and then inject the solution in HPLC apparatus (6.7). Solutions should be analysed within 24 h.

38、8.2 Calibration Determine the retention times of NBPT and NPPT by using the calibration solutions (5.8, 5.9 and 5.10). Activate the measure with the three different calibration solutions C1, C2 and C3 (manual handling or optional use of an auto sampler). 8.3 Blank test For each series of determinati

39、on carry out a blank test using an urea solution containing 30 g urea in 1 000 ml of water. Place the sample in the auto sampler and activate the measure. 8.4 Calculation and expression of the results1)8.4.1 Concentration of NBPT Calculate the concentration of NBPT in the sample solution by the exte

40、rnal calibration. Calculate the mass fraction of NBPT, wNBPT, in percent of the sample by dividing by the fertilizer content (mass concentration) of the sample solution according to Formula (1): 1) Calibration curve e.g. calculated by the software of the HPLC apparatus can be used optionally. DIN EN

41、 16651:2015-07 EN 16651:2015 (E) 7 1004NBPTAwRVm=(1) where A is the peak area for NBPT; R is the response factor (see Formula (3), peak area/g NBPT); V is the injection volume in microlitres; m is the mass of the test portion weighed into the test solution (250 ml), in grams. 8.4.2 Concentration of

42、NPPT Calculate the concentration of NPPT in the sample solution by the external calibration. Calculate the mass fraction of NPPT, wNPPT, in percent of the sample by dividing by the fertilizer content (mass concentration) of the sample solution according to Formula (2): 1004NPPTAwRVm=(2) where A is t

43、he peak area for NPPT; R is the response factor (see Formula (4), peak area/g NPPT); V is the injection volume in microlitres; m is the mass of the test portion weighed into the test solution (250 ml), in grams. 8.4.3 External response factors 8.4.3.1 Calculate the external standard response factor,

44、 RNBPT, from the average of the peak areas and mass concentrations of NBPT of the three calibration standards according to Formula (3): 123 12311 2 2 333CC C CC CNBPTNBPTC C NBPTC C NBPTC C( )( )( )RRR AAARVVV+ += =+ + (3) where RC1,RC2,RC3are the response factors of the calibration standard; AC1,AC

45、2,AC3 are the peak areas of the calibration standard; NBPTC1, NBPTC2,NBPTC3 are the mass concentrations of NBPT of the calibration standard C1, C2 and C3, in milligrams per millilitre; VC1,VC2,VC3 are the injection volumes of the calibration solution in microlitres. 8.4.3.2 Calculate the external st

46、andard response factor, RNPPT, from the average of the peak areas and mass concentrations of NPPT of the three calibration standards according to Formula (4): 123 12311 2 2 333CC C CC CNPPTNPPTC C NPPTC C NPPTC C( )( )( )RRR AAARVVV+ += =+ + (4) DIN EN 16651:2015-07 EN 16651:2015 (E) 8 where RC1,RC2

47、,RC3are the response factors of the calibration standard; AC1,AC2,AC3 are the peak areas of the calibration standard; NPPTC1, NPPTC2,NPPTC3 are the mass concentrations of NPPT of the calibration standard C1, C2 and C3, in milligrams per millilitre; VC1,VC2,VC3 are the injection volumes of the calibr

48、ation solution in microlitres. 8.4.4 Calculation of the total content Calculate the total active-ingredient content, wTby addition of the calculated contents of NBPT and NPPT according to Formula (5). T NBPT NPPTww w= + (5) 8.5 Environmental aspects The substances, solutions, eluents and packaging m

49、aterials should be disposed under consideration of safety data sheets and in accordance with local, state and federal regulations. 9 Precision 9.1 Inter-laboratory test An inter-laboratory test has been carried out in 2013 with 11 participating laboratories and four different samples of fertilizers. This test yielded the data given in Annex A. The values derived from this inter-laboratory test may not be applicable to concentration ranges and matrices other than those given in Annex A. 9.2 Repeatability