BS EN 15705-2010 Fertilizers - Determination of urea condensates using high-performance liquid chromatography (HPLC) - Isobutylidenediurea and crotonylidenediurea (method A) and me.pdf

1、BS EN 15705:2010ICS 65.080NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDFertilizers Determination of ureacondensates usinghigh-performanceliquid chromatography(HPLC) Isobutylidenediureaandcrotonylidenediurea(method A) andmethylen-ureaoligomers (method B)This B

2、ritish Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 30 June2010 BSI 2010ISBN 978 0 580 68255 1Amendments/corrigenda issued since publicationDate CommentsBS EN 15705:2010National forewordThis British Standard is the UK implementation of EN 15705:2010. Itsup

3、ersedes DD CEN/TS 15705:2009 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/37, Fertilisers and related chemicals.A list of organizations represented on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

4、include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS EN 15705:2010EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15705 March 2010 ICS 65.080 Supersedes CEN/TS 1570

5、5:2009English Version Fertilizers - Determination of urea condensates using high-performance liquid chromatography (HPLC) - Isobutylidenediurea and crotonylidenediurea (method A) and methylen-urea oligomers (method B) Engrais - Dosage des condensats dure par chromatographie liquide haute performance

6、 (HPLC) - Isobutylidne diure et crotonylidne diure (mthode A) et oligomres de mthylne-ure (mthode B) Dngemittel - Bestimmung von Harnstoffkondensaten mit Hochleistungs-Flssigchromatographie (HPLC) - Isobutylidendiharnstoff und Crotonylidendiharnstoff (Verfahren A) und Methylenharnstoff-Oligomere (Ve

7、rfahren B) This European Standard was approved by CEN on 21 February 2010. 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 bibliog

8、raphical 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 translation under the responsibility of

9、 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, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Icela

10、nd, 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: Avenue

11、Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15705:2010: EBS EN 15705:2010EN 15705:2010 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Terms and definitions .54 Sa

12、mpling and sample preparation .55 Method A: Determination of CDU and IBDU .56 Method B: Determination of methylen-urea oligomers (MU) 87 Precision method A and method B . 138 Test report . 14Annex A (informative) Results of the inter-laboratory tests 15Annex B (informative) Chromatogram and calibrat

13、ion curves method A 17Annex C (informative) Chromatogram and calibration curves method B 19Bibliography . 22BS EN 15705:2010EN 15705:2010 (E) 3 Foreword This document (EN 15705:2010) has been prepared by Technical Committee CEN/TC 260 “Fertilizers and liming materials”, the secretariat of which is h

14、eld 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 September 2010, and conflicting national standards shall be withdrawn at the latest by September 2010. This document supersedes CEN/TS 1

15、5705:2009. 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 has been prepared under a mandate given to CEN by the Europea

16、n Commission and the European Free Trade Association. The following has been added to the former edition of the European Standard: a) introduction; b) information concerning the preparation of the standard substances MDU and DMTU. According to the CEN/CENELEC Internal Regulations, the national stand

17、ards 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, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, P

18、oland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. BS EN 15705:2010EN 15705:2010 (E) 4 Introduction Fertilizers containing the condensates of urea and specified aldehydes (with crotonaldehyde called crotonyliden diurea or CDU, with isobutyraldehyde called is

19、obutylidene diurea or IBDU, with formaldehyde called urea formaldehyde or methylene urea or MU) are covered by Annex I of the Regulation (EC) 2003/2003 1 as nitrogenous fertilizers. The methods described in this European Standard enable the quantitative determination of these condensates and the det

20、ermination of the solubility of the MU-oligomers according to the Regulation. BS EN 15705:2010EN 15705:2010 (E) 5 1 Scope This European Standard specifies methods for the determination of isobutylidenediurea (IBDU), crotonylidenediurea (CDU) (method A) and methylene-urea oligomers (MU) (method B) in

21、 fertilizers using high-performance liquid chromatography (HPLC). The method is applicable to all fertilizers which do not contain interfering organic compounds. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, on

22、ly 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: Sample preparation EN 12944-1:1999, Fertilizers and liming materials and soil im

23、provers 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

24、 of this document, the terms and definitions given in EN 12944-1:1999 and EN 12944-2:1999 apply. 4 Sampling and sample preparation Sampling is not part of the method specified in this European Standard. A recommended sampling method is given in EN 1482-1. Sample preparation shall be carried out in a

25、ccordance with EN 1482-2. 5 Method A: Determination of CDU and IBDU 5.1 Principle The sample is extracted with water and, after appropriate dilution, analyzed using a suitable HPLC system. 5.2 Reagents 5.2.1 Reagents of recognized analytical grade and distilled or demineralized water (grade 3 accord

26、ing to EN ISO 3696:1995). 5.2.2 Acetonitrile, p.a., HPLC-grade. BS EN 15705:2010EN 15705:2010 (E) 6 5.2.3 Isobutylidenediurea and crotonylidenediurea, in their pure form. 5.3 Apparatus 5.3.1 Laboratory equipment and glassware, for preparation of solutions and dilutions. 5.3.2 Analytical balance, cap

27、able of weighing to an accuracy of 0,1 mg. 5.3.3 HPLC-system, with UV-detector. 5.3.4 Ultrasonic bath 5.3.5 Magnetic stirrer 5.3.6 Disposable filter, 0,45 m. 5.4 Procedure 5.4.1 System parameters of HPLC Analytical/separating column: silica column with C18 reverse phase 1)Detection wavelength: 200 n

28、m Eluent: acetonitrile/water: 10/90 (volume fraction) Flow rate: 1 ml/min Temperature: ambient temperature Injection volume: 20 l 5.4.2 Calibration 5.4.2.1 Stock solution IBDU (IBDU) = 100 mg/l Weigh 100/R mg of IBDU (5.2.3), where R is the purity of IBDU, into a 1 000 ml flask and add about 900 ml

29、of water (5.2.1). Dissolve in an ultrasonic bath (5.3.4) for about 10 min, followed by stirring on a magnetic stirrer (5.3.5) for about 1 h. Make up to volume. Filtration is not necessary. 5.4.2.2 Stock solution CDU (CDU) = 100 mg/l Weigh 100/R mg of CDU (5.2.3) , where R is the purity of CDU, into

30、a 1 000 ml flask and add about 900 ml of water (5.2.1). Dissolve in an ultrasonic bath (5.3.4) for about 10 min, followed by stirring on a magnetic stirrer (5.3.5) for about 1 h. Make up to volume. Filtration is not necessary. 5.4.2.3 Calibration solution For calibration, prepare three solutions acc

31、ording to Table 1 using one-mark (bulb) pipettes and dilute to the mark with water (5.2.1). 1)LiChrosorb RP-18 7 m 250/4 mm is an example of a suitable product available commercially. This information is given for the convenience of users of this European Standard and does not constitute an endorsem

32、ent by CEN or CENELEC of this product. BS EN 15705:2010EN 15705:2010 (E) 7 For the determination of the retention time, dilute 10 ml of the stock solution 5.4.2.1 or respectively 5.4.2.2 into two 100 ml flasks and make up to volume with water (5.2.1). The evaluation of calibration is carried out man

33、ually or by means of a suitable PC-aided (computerized) calculation method. Table 1 Preparation of calibration solutions Parameter Amount of stock solution IBDU/CDU ml (to be added to the 100 ml flask) Content of IBDU mg/l Content of CDU mg/l Standard 1 10 10,0 10,0 Standard 2 25 25,0 25,0Standard 3

34、 50 50,0 50,0 5.4.3 Preparation of the test portion Weigh 1 g of the sample grounded to 0,2 mm to the nearest 0,1 mg and flush into a 1 000 ml volumetric flask with water (5.2.1). Fill the flask to an amount of approximately 900 ml and treat it for 10 min in the ultrasonic bath (5.3.4). Then make up

35、 to the mark and stir for 1 h at room temperature on a magnetic stirrer (5.3.5). Dilute 10 ml of the solution in a 100 ml volumetric flask and filter into the HPLC injection vial through a disposable filter (5.3.6). 5.4.4 Measurement Measurement is performed manually or by means of an automatic samp

36、le loading system (autosampler). 5.4.5 Important annotations IBDU is able to form urea in aqueous solution. Therefore, the measurement of the calibration and sample solutions shall be completed within one working day. The concentrations of CDU and IBDU in the sample solutions shall be kept within th

37、e calibration limits (5.4.2) to ensure sufficient reproducibility. 5.5 Calculation The calculation can be performed manually or by means of a PC using the calibration parameters in respect to the amount used. In the case of PC-aided (computerized) calculation and application of Table 1 regarding the

38、 amounts of stock solution, the content of IBDU/CDU in milligrams per litre will be calculated by the system. The calculated values are equal to the percentage mass concentration of IBDU/CDU in the analysed sample of fertilizer. Following general rules for declaration in regulations to declare the c

39、ontent of the compounds as percentage mass fraction of nitrogen, calculate the contents, wN(IBDU)/wN(CDU)in percent (g/100 g), according to the following equations: 322,0IBDU(IBDU)N= ww (1) BS EN 15705:2010EN 15705:2010 (E) 8 0,326CDUN(CDU)= ww (2) where 0,322 is the conversion factor for the conten

40、t of IBDU in the fertilizer into nitrogen content; 0,326 is the conversion factor for the content of CDU in the fertilizer into nitrogen content. 6 Method B: Determination of methylen-urea oligomers (MU) NOTE By the condensation of urea and formaldehyde several oligomers like methylendiurea (MDU), d

41、imethylen-triurea (DMTU), trimethylen-tetraurea (TMTU) and higher oligomers are formed. These three molecules are the most soluble in water, the higher compounds are insoluble in hot water, but their nitrogen is available for plants by microbiological decomposition. Also urea is always a companion o

42、f MU oligomers. 6.1 Principle The sample is extracted with boiling water and analyzed using a suitable HPLC system. The methylen-urea soluble oligomers are measured and detected by the HPLC-method. In the HPLC-diagram methylen-urea oligomers are represented by different peaks: urea, methylen-diurea,

43、 dimethylen-triurea; trimethylen-tetraurea are, in the mean time, the most soluble and important. 6.2 Reagents 6.2.1 Reagents of recognized analytical grade and distilled or demineralized water (grade 3 according to EN ISO 3696:1995). 6.2.2 Acetonitrile, p.a., HPLC-grade. 6.2.3 Urea, p.a., 46,6 % of

44、 total nitrogen. 6.2.4 Methylen-diurea (MDU), synthesized and purified by a special laboratory, 42,4 % of total nitrogen.2)6.2.5 Dimethylen-triurea (DMTU), synthesized and purified by a special laboratory, 41,2 % of total nitrogen. 2)6.2.6 Trimethylen-tetraurea (TMTU), synthesized and purified by a

45、special laboratory, 40,6 % of total nitrogen. 6.3 Apparatus 6.3.1 Laboratory equipment and glassware, for preparation of solutions and dilutions. 6.3.2 Analytical balance, capable of weighing to an accuracy of 0,1 mg. 6.3.3 Technical balance, capable of weighing to an accuracy of 0,01 g. 6.3.4 HPLC-

46、system, equipped with an UV-detector. 2)The standard substances MDU and DMTU can be prepared according to the method given in Official Methods of Analysis of AOAC International, AOAC Official Method 983.01, JAOAC 66, 769 (1983). BS EN 15705:2010EN 15705:2010 (E) 9 6.3.5 Ultrasonic bath 6.3.6 Magneti

47、c stirrer 6.3.7 Disposable filter, 0,45 m. 6.4 Procedure 6.4.1 System parameters of HPLC Analytical/separating column NH2column, 5 m, 250 mm 4,6 mm 3)A guard-column is recommended. Detection wavelength 195 nm (Diode Array detector) Eluent acetonitrile/water 85/15 (volume fraction) Flow rate 1 ml/min

48、 Temperature 60 C Run time 30 min Injection volume 20 l 6.4.2 Calibration 6.4.2.1 Stock solution of urea, 1 000 mg/kg Weigh (6.3.2) 100/R mg of urea (6.2.3), where R is the purity of urea, to the nearest 0,1 mg and put into an empty and dry 100 ml volumetric flask, weighed (6.3.3) before to the near

49、est 0,01 g. Add 50 ml of water (6.2.1) and dissolve the urea in an ultrasonic bath (6.3.5) for about 10 min. Make up approximately to the mark with water (6.2.1) and homogenize. Weigh (6.3.3) the full flask to the nearest 0,01 g and record the net weight. Store at room temperature, well closed. This stock solution is stable for one week. 6.4.2.2 Stock solution of methylen-diurea, 1 000 mg/kg Weigh (6.3.2) 50/R mg of MDU (6.2.4), where R is the purity of MDU, to the