1、BRITISH STANDARD Fertilizers - Treatment with a cation exchange resin for the determination of the chelated micro-nutrient content and of the chelated fraction of micro-nutrients The European Standard EN 13366:2001 has the status of a British Standard ICs 65.080 BS EN 13366:2001 NO COPYING WITHOUT B
2、SI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW STD=BSI BS EN L33bb-ENGL 2OOL = 3b2Ybb9 0930855 445 = BS EN 13366:2001 National foreword This British Standard is the official English language version of EN 13366:2001. The UK participation in its preparation was entrusted to Technical Committee CI
3、U37, Fertilizers and related chemicals, which has the responsibility to: - - aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and Europea
4、n developments and promulgate them in the UK. - A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standa
5、rds Catalogue under the section entitled “International Standards Correspondence Inde?, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for
6、 their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. This British Standard, having been prepared under the direction of the Seetor Committee for Materials and Chemicals, was published under the authority of the Standards Committee
7、and comes into effect on 15 May 2001 Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 11 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Am
8、d. No. IDate I Comments 8 BSI 05-2001 ISBN O 580 37283 9 STD-BSI BS EN 133bb-ENGL 2001 lb2Libb7 071085b 381 M EUROPEAN STANDARD EN 13366 NORME EUROPENNE EUROPISCHE NORM January 2001 ICs 65.080 English version Fertilizers - Treatment with a cation exchange resin for the determination of the chelated
9、micro-nutrient content and of the chelated fraction of micro-nutrients Engrais - Traitement avec une rsine changeuse dions cationique pour la dtermination de la teneur en oligo- lments chlates et de la fraction chlate des oligo- lments Dngemittel -Behandlung mit einem Kationenaustauscherharz zur Bes
10、timmung des chelatisierten Spurennhrstoffgehaltes und des chelatgebundenen Anteils von Spurennhrstoffen This European Standard was approved by CEN on 1 January 2001. CEN members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions for giving this European Stan
11、dard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, G
12、erman). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, F
13、inland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMTTEE FOR STANDARDIZATION EUROPAISCHES KOMITEE FOR NORMUNG COMITB EUROPEEN DE NORMALISATION Management Centre: rue de Siassari, 36 8-1050 Br
14、ussels O 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13366:2001 E STD-BSI BS EN 133bb-ENGL 2001 D Bb2LibbS OSBO857 218 Page 2 EN 13366:2001 Contents Foreword . 3 I Scope . 3 2 Normative references . 4 3 Terms and definitio
15、ns . 4 4 Principle . 4 5 Interferences 5 6 Apparatus 5 7 Reagents 5 8 Procedure 7 9 Expression of results . 9 io Precision 9 11 Test report . 10 Bibliography . 11 8 BSI 052001 STDOBSI BS EN 133bb-ENGL ZOOL 3b24bb9 0930858 354 = Page 3 EN 13366:2001 Foreword This European Standard has been prepared b
16、y Technical Committee CENRC 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 latest by July 2001, and conflicting national stan
17、dards shall be withdrawn at the latest by July 2001. According to the CENICENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland,
18、 Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. O BSI 052001 STD=BSI BS EN 133bb-ENGL 2001 3bZqbbS 0730857 O70 Page 4 EN 13366:2001 1 Scope This standard defines a method for the treatment with a cation exchange resin for the determinati
19、on of the chelated micro-nutrient content and the chelated fraction of the micro-nutrients (trace elements) cobalt, copper, iron, manganese, and zinc in fertilizers. This method applies to fertilizers containing one or more of the micro-nutrients cobalt, copper, iron, manganese, and zinc, chelated b
20、y one or more chelating agents of the group of the polyamino polycarboxylic acids, previously determined according to EN 13368-1 and EN 13368-2, either alone or in combination with primary (N, P, K) and/or secondary (S, Na, Ca, Mg) nutrients. The limit of determination of the chelated micro-nutrient
21、 content varies between 0,005 % in simple matrices with high amounts of chelated micro-nutrients, and 0,5 % in more complex cases (see 7.2). 2 Normative references This European standard incorporates by dated or undated reference, provisions from other publications. These normative references are ci
22、ted at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European standard only when incorporated in it by amendment or revision. For undated references, the latest edi
23、tion of the publication referred to applies (including amendments). EN 1482, Sampling of solid fertilizers and liming materials. EN 13368-1, Fertilizers - Determination of chelating agents in fertilizers by ion chromatography - Part I:EDTA, HEDTA and DTPA. EN 13368-2, Fertilizers - Determination of
24、chelation agents in fertilizers by ion chromatography - Part 2:EDDHA and EDDHMA. EN IS0 3696, Water for analytical laboratory use - Specification and test methods (IS0 3696:7987). 3 Terms and definitions For the purposes of this standard the following terms and definitions apply: 3.1 chelated fracti
25、on chelated content of a micro-nutrient, divided by its total content, and expressed as a percentage 4 Principle The sample is extracted with water and the extract adjusted to a neutral pH. The chelated forms of an element thus having a negative andlor neutral charge are not retained by an ion excha
26、nge resin of the strong sulfonated cationic type, and are separated from the non-chelated forms, having a cationic nature. The chelated forms are collected and their content determined by spectrometry, as well as the total element content. Q BSI 052001 STD-BSI BS EN 133bb-ENGL 2001 lb24bb7 07108b0 8
27、02 m Page 5 EN 13366:2001 5 Interferences Any substance combining with a micro-nutrient to form a stable, negative or uncharged compound (chelate or complex) at neutral pH, will prevent the retention by the resin, and account for a certain degree of chelation. This is the case for many complexing ag
28、ents, e.g. amino acids, citrate, and for chelating agents other than ethylenediarninetetraacetic acid (EDTA), hydroxyethyiethylenediaminetetraacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediamine-di-(o-hydroxypheny1)acetic acid (EDDHA) and ethSenediamine-di-(o-hydroxy-p-met
29、hSphenyl)acetic acid (EDDHMA). NOTE In order to confirm the presence of the statutory chelating agents in the sample, EN 13368-1 and EN 13368-2 should be applied. In some cases, especially where complex fertilizer matrices with high amounts of phosphate are handled, or where micro-nutrients with a l
30、ow chelated fraction are present, slow precipitation reactions can occur during the contact with the resin, causing equilibrium shifts, adsorption, decreasing the exchange capacity and leading to inaccurate and imprecise results. It is advised to proceed as soon as possible with all steps. Highly un
31、stable solutions cannot be considered. 6 Apparatus NOTE All glassware, filters, and equipment parts coming in contact with samples and solutions, should be appropriate for micro-nutrient analysis, be very clean and free from contamination, especially by the elements Co, Cu, Fe, Mn and Zn. Usual labo
32、ratory equipment and in particular: 6.1 Sieve, sieve having a plastic body and a nylon mesh of aperture size less than the minimum diameter of the resin particles. The mass of the dry sieve shall be determined to within 0,Ol g. 6.2 Tumbling shaker, tumbling or rotary shaker operating at a rotational
33、 speed between 30 min and 40 min-, at a temperature of 18 “C to 22 “C. 6.3 Conductivity meter, equipped with a conductivity cell and a temperature controller. The cell shall be rinsed and dried before immersion, and calibrated with a 0,Ol mol/l potassium chloride solution, having a specific conducti
34、vity at 20 “C of 1,28 mSlcm. 6.4 Shaking flasks, polyethylene flasks, each having a capacity of 50 ml and a stopper. 6.5 Membrane filters, micromembrane filters resistent to aqueous solutions, with porosity of 0,45 pm. 7 Reagents 7.1 General a) all water used should conform to EN IS0 3696 and be deg
35、assed by boiling before use; b) all reagents should be of recognized analytical grade. O BSI 05-2001 STDOBSI BS EN 133bb-ENGL 2001 1b2rlbbS 09108bl 747 Page 6 EN 13366:2001 7.2 Sulfonated cationic exchange resin 7.2.1 General Polystyrene divinylbenzene (PS-DVB) copolymer, slightly crosslinked (mass
36、fraction of DVB less than or equal to 8 %), in sodic or protonic form, free from Co, Cu, Fe, Mn, and Znl). 7.2.2 Preparation and determination of exchange capacity Protonate the resin prior to use, transform to the sodic form, to eliminate any contamination and measure the cationic exchange capacity
37、 (CEC) of the sodic resin in wet form as follows: - Transfer 50 g of resin to a 500 ml beaker and add 250 ml of hydrochloric acid solution (7.4). - Place on a magnetic stirrer. - After 1 h of moderate stirring, the suspension is transferred onto the sieve (6.1). - The resin is recovered and transfer
38、red back to the beaker. - The acidification and separation operations are repeated as described. - At the end of the second operation, the protonated resin present on the sieve is washed thoroughly with water until the rinsing water is free from chloride when tested with silver nitrate. - Transfer t
39、he wet protonated resin into a 500 ml beaker and add 250 ml of sodium chloride solution (7.5). - While stirring on a magnetic stirrer and using a pH meter, titrate the resin using the sodium hydroxide solution (7.6) until a stable pH of 7,O is obtained. - Let Vo be the required volume of NaOH (7.6),
40、 in millilitres. - Transfer quantitatively the resin that is now in sodic form onto the sieve (6.1). - Rinse thoroughly with water until the rinsing water is free from chloride (silver nitrate test). - Once rinsing is complete, allow the resin to drain. - Weigh the drained wet resin to within 0,Ol g
41、. Let P be the mass in grams. - The wet sodic resin can be stored in a stoppered opaque flask at ambient temperature for 2 years. The cationic exchange capacity of the resin is given by the following formula: where: CEC is the cationic exchange capacity, in millimoles per gram of wet resin 7.3 Hydro
42、chloric acid, c(HCI) = 6 mol/l Hydrochloric acid, diluted 1 + 1 with water. 7.4 Hydrochloric acid solution, c(HCI) = 1 mol/l Dilute 165 ml of hydrochloric acid solution (7.3) to I I. Dowex 50 x 4-400, Amberlite IR 120 or equivalent are examples of suitable products available commercially. This infor
43、mation is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of these products. 8 BSI 052001 Page 7 EN 13366:2001 Micro-nutrient content (%) Mass of sample E (9) Volume of the extract V (mi) 7.5 Dissolve 58,4 g of NaCI in water and dilute to 1
44、I. Sodium chloride solution, c(NaCI) = 1 mol/l e 0,Ol 0,Ol - 5 10 5 2 250 500 500 7.6 Sodium hydroxide solution, c(Na0H) = 2 molil Carefully dissolve 80,O g of NaOH in water and dilute to 1 I. 7.7 Dilute 25 ml of the sodium hydroxide solution (7.6) to 500 ml. Sodium hydroxide solution, c(Na0H) = 0,l
45、 mol/l 7.8 Nitric acid solution, c(HN03) = 0,l mol/l Carefully dilute 6,9 ml of nitric acid (65 % “O3 , p = 1,40 glml) to 1 I. 7.9 Sodium hydroxide solution, c(Na0H) = 0,Ol moll1 Dilute 50 ml of the sodium hydroxide solution (7.7) to 500 ml. 7.10 Dilute 50 ml of the nitric acid solution (7.8) to 500
46、 ml. Nitric acid solution, c(HN03) = 0,Ol moll1 8 Procedure 8.1 Preparation of the sample Prepare the sample according to EN 1482. NOTE 1 Sample may also be prepared according to method 1 (see I of bibliography). NOTE 2 For the size reduction of samples with a high amount of chelating agents, it is
47、not recommended to use a high speed laboratory mill. It is more convenient to grind the sample in a mortar to a particle size less than 1 mm. 8.2 Extraction of the sample - Weigh an amount of sample, depending on the declared content of water soluble micro-nutrient, to within 1 mg, into a volumetric
48、 flask of 250 ml or 500 ml, according to Table 1: Table 1 - Sample mass/volume ratios - Add about 200 ml of water for a 250 ml flask, or about 400 ml for a 500 ml flask. - Stopper the flask, shake well to disperse the matter, and put on the tumbling shaker (6.2) for 30 min. - Adjust to the mark with
49、 water, homogenize, and filter. O BSI 052001 Page 8 EN 13366:2001 - By means of a conductivity meter (6.3), measure the specific conductivity at 20 “C of the filtrate. This shall not exceed 1,5 mS/cm. Otherwise dilute the filtrate, in order to obtain a solution with a specific conductivity at 20 “C not higher than 1,5 mS/cm. Let D be the dilution factor. NOTE 1 Aqueous sample extracts cannot be stabilized by acidifying since in acid conditions, chelates can dissociate or precipitate, and the resin can be protonated. It is essential to proceed i
