1、BRITISH STANDARD Soil improvers and growing media - Extraction of aqua regia soluble elements The European Standard EN 13650:2003 has the status of a British Standard ICs 65.080 NO COPYING WITHOUI BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHl LAW BS EN 13650:2001 BS EN 13650:ZOOl National foreword
2、 This British Standard is the official English language version of EN 13650:ZOOl. The UK participation in its preparation was entrusted to Technical Committee AW120, Top soil and other growing media, which has the responsibility to: - - aid enquirers to understand the text; present to the responsibl
3、e European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. - A list of organizations represented on this committee can be obtained on request to its secr
4、etary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standard
5、s Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application Compliance with a British Standard does not of itself confer immunity from legal obligations. This British Stand
6、ard, having been prepared under the direction of the Consumer Products and Services Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on O9 November 2001 Summary of pages This document comprises it front cover, an inside front cove
7、r, the EN title page, pages 2 to I7 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued Amendments issued since publication C BSI O9 November 2001 Amd. No: IDate IComments - _ ISBN O 580 38269 9 EN 13650 EUROPEAN STANDARD NORME EUROPENNE EU
8、ROPISCHE NORM September 2001 ICs 65.080 English version Soil improvers and growing media - Extraction of aqua regia soluble elements Amendements du sol et supports de culture - Extraction delments solubles dans leau rgale Bodenverbesserungsmitiel und Kultursubstrate - Extraktion von in Knigswasser l
9、slichen Elementen This European Standard was approved by CEN on 11 August 2001. CEN members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Upto-date lists and bib
10、liographical 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, German). A version in any other language made by translation under the responsibility of
11、 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, Finland, France, Germany, Greece, Iceland, Ireland, Italy. Luxembourg, Netherlands, Norw
12、ay, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMmEE FOR STANDARDIZATIOK EUROPISCHES KOMITEE FUR NORMUhC; COMITE EUROPEEN DE NORMALISATIOK Management Centre: rue de Stassar, 36 8-1050 Brussels O 2001 CEN All rights of exploitation in any form and by any means reserved worldw
13、ide for CEN national Members. Ref. No. EN 13650:2001 E EN 13650:2001 (E) Contents Page Foreword . 3 1 2 3 4 5 6 7 8 9 IO 11 12 Scope 4 Normative references 4 Terms and definitions . 4 Principle . 4 Reagents 5 Apparatus . 5 Test sample passing through a 500 pm sieve 6 Procedure . 6 Determination of e
14、xtracted elements 7 Expression of results 7 Precision 7 Test Rep0 rt . 7 Annex A (informative) Results of an interlaboratory trial to determine aqua regia soluble elements . 9 Annex B (informative) Methods of analysis used in the interlaboratory trial 16 Bibliography 17 2 EN 13650:2001 (E) Foreword
15、This European Standard has been prepared by Technical Committee CENTTC 223 “Soil improvers and growing media“, the secretariat of which is held by BSI. 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
16、 by March 2002, and conflicting national standards shall be withdrawn at the latest by March 2002. The annexes A and B are informative. According to the CENICENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Au
17、stria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy. Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 3 EN 13650:2001 (E) SAFETY PRECAUTIONS - Care should be taken when handling samples that may contain sharp
18、s or are of a dusty nature. i Scope This European Standard specifies a method for the routine extraction of aqua regia soluble elements (as listed in annex B) from soil improvers or growing media. Materials containing more than about 28 % (m/m) organic matter will require treatment with additional n
19、itric acid. With high solute concentrations in extract solutions, spectral interferences and background enhancement should be expected. The method is not applicable to liming materials and preformed materials such as mineral wool slabs and foam slabs. NOTE 1 Aqua regia will not totally dissolve most
20、 soil improvers or growing media, and the efficiency of extraction for particular elements differs from element to element. Such efficiency might also differ for the same element in different matrices. Elements extractable in aqua regia cannot therefore, be described as “Totals”; conversely they can
21、not be regarded as the ”bio- available” fraction, as the extraction procedure is too vigorous to represent any biological process. NOTE 2 concerned. The requirements of the standar may differ from the national legal requirements for the declaration of the products 2 Normative references This Europea
22、n Standard incorporates h y- dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendm-lnts to or revisions of any of these publication
23、s apply to this European Standard only when incorporated in it bv amendment or revision. For undated references the latest edition of the publication referred to applies (includincj amendments). EN IS0 3696, Water for analytical laboistory use - Specification and test methods (IS0 3696:1987). EN 130
24、39, Soil improvers and growing media - Determination of organic matter content and ash. EN 13040:1999, Soil improvers and growing media - Sample preparation for chemical and physical tests, determination of dry matter content, moisture content and laboratory compacted bulk density. 3 Terms and defin
25、itions For the purposes of this standard the ternis and definitions given in EN 13039 and EN 13040 apply. 4 Principle The dried sample is finely ground and exiracted with a hydrochloriclnitric acid mixture by standing for 16 h ar room temperature, followed by boiling undei reflux for 2 h. The extrac
26、t is clanfied and the extracted elements determined. The test sample shall be ground to less than 500 pm prior to aqua regia digestion. Such grinding is designed io a) give a more homogeneous sample from which a sub-sample is taken; b) increase the efficiency of acid attack hy increasing the surface
27、 area of the particles. 4 EN 13650:2001 (E) 5 Reagents 5.1 General All reagents used shall be of recognized analytical quality. Use water of grade 2 complying with EN IS0 3696. Deionized water may be used, providing that it meets the requirements given above. It is recommended that the same batch of
28、 water be used throughout a given batch of determinations and that blank determinations are carried out. 5.2 Hydrochloric acid, c(HCI) = 12 mol/l; p = 1 ,I 8 glml; 37 % masslvolume. 5.3 Nitric acid, o(HN03) = 15 molll; p I 1,42 glml; not less than 65 % masslvolume. 5.4 Nitric acid, o(HN03) = 03 moll
29、l. 35 ml nitric acid (5.3) is diluted to one litre of water 6 Apparatus 6.1 General NOTE for the determinations given in annex B, in order to reduce the possibility of within-laboratory contamination. Clean all new glassware by carefully immersing in warm nitric acid (5.4) for a minimum of 6 h and t
30、hen rinse in water. It has been found convenient to keep separate sets of glassware including antibumping granules or roughened beads The apparatus consists of the usual laboratory apparatus, and in particular the following : 6.2 Grinding mill, capable of grinding dried samples to a size less than 5
31、00 pn without contamination by the elements to be determined. A mill causing little or no contamination is essential, as is adequate cleaning between samples to eliminate memory . effects. Both agate and zirconium oxide mills have been found suitable. 5 6.3 Test sieve, of aperture size 500 pm, e.g.
32、test sieve with gauze preferably made from plastic materials, e.g. nylon. 6.4 Desiccator, of nominal volume 2 I. 6.5 Reaction vessel, of nominal volume of not less than 250 ml. NOTE 1 with ground-glass joints and a drip funnel of nominal value 100 ml with conical ground-glass joints and stopper. NOT
33、E 2 excessive frothing is experienced. It has been found convenient to use for mixing a two-neck Erlenmeyer type reaction vessel of nominal value 500 ml A larger reaction vessel may be required for samples when a sample weight exceeding 1 g is taken for analyses or 6.6 Reflux condenser, straight-thr
34、ough type, with conical ground-glass joints. NOTE Water-cooled condensers with a minimum effective length of at least 200 rnm have been found suitable. The effective length is the internal surface, which is in contact with the cooling water. The overall external length of such condensers is usually
35、at least 363 rnrn. 6.7 Roughened glass beads, diameter 2 mm to 3 mm (or anti-bumping granules). 6.8 Temperature-controlled heating apparatus, capable of heating the contents of the reaction vessel to reflux tem perature. 6.9 Funnel, of diameter approximately 100 mm. 6.10 Volumetric flask, of nominal
36、 capacity 100 ml. 5 EN 13650:2001 (E) 6.11 Filter papers, cellulose-based ashless types, with a medium pore size of approximately 8 pm and diameter of 150 mm. 6.12 Analytical balance, capable of weighing accurately to 1,0 mg. 7 Test sample passing through a 500 pm sieve Take approximately 5 g of the
37、 sample prepared in accordance with EN 13040:1999, clause 9, and grind the sub- sample using a mill (6.2) until all the sub sample has passed through the sieve (6.3). 8 Procedure 8.1 WARNING - Digestions with hydrochloric and nitric acid are potentially hazardous and laboratory coats, gloves and saf
38、ety spectacles or goggles shall be used. The digestion shall be carried out in a well-ventilated fume cupboard with the reflux digestion on a temperature - controlled heating apparatus. It is essential to add antibumping granules (or roughened glass beads) both to the blank and the samples to preven
39、t bumping and loss of solution. It is important to maintain gentle reflux, both of the blank and the test samples, to avoid temperature fluctuations, which could cause local superheating. The toxicity or carcinogenicity of each reagent used in this method has not been precisely defined; however, eac
40、h chemical compound needs to be treated as a potential health hazard. From this viewpoint, reduce exposure to these chemicals to the lowest possible level by whatever means available. Toxic fumes are evolved by nitric acid. Always use the concentrated acid in a fume cupboard. 8.2 Digestion Weigh app
41、roximately 1 g to 3 g, to the nearest 0.001 g. of the finely ground test sample (clause 7) into the reaction vessel (6.5). Moisten with about 0,5 ml to 1,0 rnl water. Add while mixing, 21 ml of hydrochloric acid (5.2) followed by 7 ml of nitric acid (5.3), drop by drop if necessary to reduce foaming
42、. Allow to stand for 16 h at room temperature to allow for slow oxidation of the organic matter in the sample. NOTE 1 It is common practice to add hydrochloric acid directly to the reaction vessel, followed by the nitric acid, and to assume that the aqua regia forms in the reaction vessel. However,
43、problems have been encountered with materials rich in carbonates. where a substantial portion of the hydrochloric acid has been consumed before the nitric acid can be added. Under such circumstances. the correct formation of aqua regia is doubtful. The amount of aqua regia is sufficient only for oxi
44、dation of about 0,85 g of organic matter. If there is any doubt about the amount of organic matter present, carry out a determination according to EN 13039. If there is more than 0,85 g of organic matter (corresponding to about 0,5 g of organic carbon) in the test sample reduce the quantity of sampl
45、e analyzed or proceed as follows. Allow the first reaction with aqua regia to subside. Then add an extra 1 ml of nitric acid (5.3) only to every 0,17 g of organic matter above 0,85 g. Do not add more than 10 ml of nitric acid at any time. and allow any reaction to subside before proceeding further.
46、Add a few roughened glass beads (6.7) and place the reaction vessel on a cool heating apparatus (6.8). Raise the temperature of the reaction mixture slowly until reflux conditions are reached and maintain for 2 h ensuring that the condensation zone is lower than 1/3 of the height of the condenser, t
47、hen allow to cool. Transfer the contents of the reaction vessel to a 100 ml volumetric flask (6.10). Wash the reaction vessel at least three times with water decanting each washing into the volumetric flask before adding the next. Dilute to the mark with water and mix. Allow to stand so that most of
48、 any insoluble residue settles out of suspension. Decant the relatively sediment-free supernatant onto a filter paper ( b) a complete identification of the sample; c) all the analytical methods used; d) the results of the determination expressed as masshacs on dry matter basis; e) the laboratory com
49、pacted bulk density; f) moisture content; 7 EN 13650:2001 (E) 9) any details not specified in the European Standard, or which are optional, as well as any other factor which may have affected the results. 8 EN 13650:2001 (E) Annex A (informative) Results of an interlaboratory trial to determine aqua regia soluble elements. An interlaboratory trial was organized 1997 under the auspices of the European Committee for Standardization, to test the procedures specified in this European Standard. In this trial the number of laboratories given in Tables A.l to A.6 determined the aq
