DIN EN ISO 23470-2011 Soil quality - Determination of effective cation exchange capacity (CEC) and exchangeable cations using a hexamminecobalt trichloride solution (ISO 23470 2007.pdf

1、September 2011 Translation by DIN-Sprachendienst.English price group 12No 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).

2、ICS 13.080.20!$ta?“1816228www.din.deDDIN EN ISO 23470Soil quality Determination of effective cation exchange capacity (CEC) andexchangeable cations using a hexamminecobalt trichloride solution(ISO 23470:2007)English translation of DIN EN ISO 23470:2011-09Bodenbeschaffenheit Bestimmung der effektiven

3、 Kationenaustauschkapazitt (KAK) und der austauschbarenKationen mit Hexammincobalt-trichlorid-Lsung (ISO 23470:2007)Englische bersetzung von DIN EN ISO 23470:2011-09Qualit du sol Dtermination de la capacit dchange cationique (CEC) effective et des cationschangeables laide dune solution de trichlorur

4、e de cobaltihexammine(ISO 23470:2007)Traduction anglaise de DIN EN ISO 23470:2011-09www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.2108.11 DIN EN ISO 23470:2011-09 2 A comma is used as the decimal marker. National foreword This st

5、andard has been prepared by Technical Committee ISO/TC 190 “Soil quality” in collaboration with Technical Committee CEN/TC 345 “Characterization of soils” (Secretariat: NEN, Netherlands). The responsible German body involved in its preparation was the Normenausschuss Wasserwesen (Water Practice Stan

6、dards Committee), Working Committee NA 119-01-02-02 UA Chemische und physikalische Verfahren. Expert assistance and specialized laboratories are recommended to perform the procedures described in this standard. The DIN Standards corresponding to the International Standards referred to in this docume

7、nt are as follows: ISO 5725-2 DIN ISO 5725-2 ISO 10390 DIN ISO 10390 ISO 11260 DIN EN ISO 11260 ISO 11465 DIN ISO 11465 National Annex NA (informative) Bibliography DIN EN ISO 11260, Soil quality Determination of effective cation exchange capacity and base saturation level using barium chloride solu

8、tion DIN ISO 5725-2, method for the determination of repeatability and reproducibility of a standard measurement method DIN ISO 10390, Soil quality Determination of pH DIN ISO 11465, Soil quality Determination of dry matter and water content on a mass basis Gravimetric method Accuracy (trueness and

9、precision) of measurement methods and results Part 2: Basic EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 23470 June 2011 ICS 13.080.20 English Version Soil quality - Determination of effective cation exchange capacity (CEC) and exchangeable cations using a hexamminecobalt trichloride sol

10、ution (ISO 23470:2007) Qualit du sol - Dtermination de la capacit dchange cationique (CEC) effective et des cations changeables laide dune solution de trichlorure de cobaltihexammine (ISO 23470:2007) Bodenbeschaffenheit - Bestimmung der effektiven Kationenaustauschkapazitt (KAK) und der austauschbar

11、en Kationen mit Hexammincobalt-trichlorid-Lsung (ISO 23470:2007) This European Standard was approved by CEN on 10 June 2011. 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 wi

12、thout any alteration. Up-to-date lists and 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 othe

13、r language made by translation under the responsibility 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,

14、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 FOR STANDARDIZATION COMIT EUROPEN DE NORMA

15、LISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 23470:2011: EContents Page Foreword3 1 Scope 4 2 Normative references 4 3 Princip

16、le4 4 Reagents.5 5 Apparatus .5 6 Procedure .6 7 Test report 11 8 Validation11 Annex A (informative) Comparison of different methods for the determination of effective CEC .12 Annex B (informative) Results of the interlaboratory comparison 17 Bibliography 19 DIN EN ISO 23470:2011-09 EN ISO 23470:201

17、1 (E) 2 Foreword The text of ISO 23470:2007 has been prepared by Technical Committee ISO/TC 190 “Soil quality” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 23470:2011 by Technical Committee CEN/TC 345 “Characterization of soils” the secretariat of whi

18、ch is held by NEN. 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 December 2011, and conflicting national standards shall be withdrawn at the latest by December 2011. Attention is drawn to the po

19、ssibility 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. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries

20、 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, Poland, Portugal, Romania, Slovakia, Slovenia,

21、 Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 23470:2007 has been approved by CEN as a EN ISO 23470:2011 without any modification. DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 3 1 Scope This International Standard specifies a method for the determination of

22、 the cation exchange capacity (CEC) and the content of exchangeable cations (Al3+, Ca2+, Fe2+, K+, Mg2+, Mn2+, Na+) in soils using a hexamminecobalt trichloride solution as extractant. NOTE As the pH of a soil suspension in the hexamminecobalt trichloride solution is close to the pH of the suspensio

23、n in water, this method is considered to give the effective CEC, i.e. the CEC at the soil pH. This International Standard is applicable to all types of air-dried soil samples which have been prepared in accordance with ISO 11464. References and results of the comparison with other methods (barium ch

24、loride, ammonium acetate) are given in Annex A. 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 (including any

25、 amendments) applies. ISO 11464, Soil quality Pretreatment of samples for physico-chemical analysis 3 Principle Cations retained by a soil sample are exchanged with the hexamminecobalt ions of an aqueous solution, with shaking for 60 min 5 min at a temperature of 20 C 2 C. The CEC is obtained by dif

26、ference between the initial quantity of hexamminecobalt in solution and the quantity remaining in the extract after the exchange reaction. The measurement of hexamminecobalt concentration in the extract can be performed by direct spectrophotometric measurement, or by the determination of total ammon

27、ium nitrogen or total cobalt concentrations. The quantities of exchanged cations are determined on the same extract using spectrometric methods, such as inductively coupled plasma atomic emission spectrometry (ICP-AES). NOTE 1 Exchangeable acidity can also be measured in the hexamminecobalt extract.

28、 NOTE 2 When exchangeable cations are held in micropores into which ammonium ions but not hexamminecobalt ions can enter, the CEC and exchangeable cation values determined with this method may be smaller than those determined by the ammonium acetate method. This has been observed in some soils conta

29、ining allophane and imogolite, for example soils developed on volcanic rocks. DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 4 4 Reagents Only reagents of recognized analytical quality shall be used. 4.1 Distilled or demineralized water, exempt from the elements under analysis and having a conductiv

30、ity of less than 0,5 Scm1. 4.2 Hexamminecobalt trichloride Co(NH3)6Cl3, 0,016 6 moll1solution. Dissolve, to within a milligram, 4,458 g of hexamminecobalt trichloride in a volumetric flask containing 700 ml of distilled water (4.1). Make up to volume and mix. NOTE Hexamminecobalt trichloride can be

31、purchased from Sigma-Aldrich or Fluka. 1)4.3 Anti-bumping granules (e.g. pumice stone in grain form, glass beads). 4.4 Boric acid (40 gl1solution). 4.5 Tashiro indicator. Dissolve 2,0 g of methyl red and 1,0 g of methylene blue in 1 000 ml of 95 ethanol. 4.6 Phenolphthalein. Dissolve 1 g of phenolph

32、thalein in 1 000 ml of 95 ethanol. 4.7 Sodium hydroxide solution, 33 % (ratio of mass to volume). 4.8 Sulfuric acid (H2SO4), 0,025 moll1standard volumetric solution. 4.9 Ammonium sulfate, for analysis. 4.10 Stock solutions of Al3+, Ca2+, Fe2+, K+, Mg2+, Mn2+, Na+, 1,000 gl1. These solutions are supp

33、lied with a certified composition from a reputable source and are checked on a regular basis. 5 Apparatus Usual laboratory apparatus and glassware, and in particular: 5.1 Analytical balance, the weighing uncertainty range of which will not exceed 0,1 % of the test portion mass. 5.2 Containers for sh

34、aking, tightly stoppered, rigid or non-rigid wall, having a volume between 75 ml and 100 ml. 5.3 50 ml distributor, set at 0,25 ml of the delivered volume. 5.4 End-over-end shaker, allowing the permanent suspension of the soil/extraction solution mixture, placed in ambient air at 20 C 2 C. 1) Sigma-

35、Aldrich and Fluka are examples of suitable products available commercially. This information is given for the convenience of users of this International Standard and does not constitute an endorsement by ISO of this product. DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 5 5.5 Slow-filtration paper

36、filters, allowing the checking of the adsorption level of the hexamminecobalt ions by the filter. If it cannot be neglected with respect to the measured CEC values, it should be taken into account (see 6.3). 5.6 Centrifuge and relevant centrifuge vials, of which the centrifugation time and speed dep

37、end on the type of centrifuge and are selected with a view to securing a clear supernatant. 4 000 r/min for 20 min are generally sufficient, but special care shall be taken due to the high content of fixed cobaltihexammine ions on colloidal particles. 5.7 Distillation apparatus, of which the differe

38、nt parts shall be assembled to ensure tightness in order to prevent any loss of ammonia or entrainment of sodium hydroxide. 5.8 Microburette. 5.9 Spectrophotometer, allowing measurements to be performed at wavelengths of 380 nm and 475 nm, equipped with a 10 mm path-length measuring cell. 5.10 Induc

39、tively coupled plasma atomic emission spectrometer (ICP-AES) or flame atomic absorption spectrometer. 6 Procedure 6.1 Test portion Pretreat soil in accordance with ISO 11464. If Q is the number of centimoles of positive charges provided by a given volume of hexamminecobalt solution, the centimoles o

40、f positive charges carried by the test portion shall lie between Q/10 and Q/3 inclusive, see Table 1. Table 1 Test portions (in 50 ml of solution 4.2) Measured CEC, cmol+kg17 Figure A.2 Comparison of the determinations of effective CEC using hexamminecobalt trichloride and ammonium acetate on 48 cul

41、tivated soil samples from France DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 13 Key X CEC using hexamminecobalt trichloride, in cmol+kg1Y CEC using ammonium acetate (see NF X31130), in cmol+kg1y = 0,989x t pH 7 Figure A.3 Comparison of the determinations of effective CEC using hexamminecobalt tri

42、chloride and CEC calculated from the measurement of CEC using ammonium acetate, pH in water (see ISO 10390), and carbon content (see ISO 14235) on 48 cultivated soil samples from France DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 14 Table A.1 Comparison of hexamminecobalt trichloride method (Cohe

43、x) according to this International Standard with ammonium acetate method (AmAc) for the determination of CEC and exchangeable cations of some volcanic soils from Japan Soil sample PA VA 576 510 w-222 w-211 w-136 Goshi Carbon, g/kg 1,38 1,92 13,06 29,39 120,48 60,61 188,64 64,67 pH (water) 6,7 6,8 5,

44、9 5,7 4,8 4,8 5 6,3 CEC ammonium acetate, cmol+/kg 25,6 12,3 18,1 20,2 35,8 25,6 47,8 36,1 Exchangeable Ca (AmAc), cmol+/kg 3,7 2,65 0,2 1,4 0,45 4,65 1 14,15 Exchangeable Na (AmAc), cmol+/kg 0,24 0,35 0,31 0,09 0,09 0,16 0,23 0,05 Exchangeable Mg (AmAc), cmol+/kg 2,4 0,96 0,06 0,38 0,38 0,41 0,71 3

45、,22 Exghangeable K (AmAc), cmol+/kg 0,32 0,14 0,26 0,6 0,49 0,85 0,54 0,9 Sum (Ca+Na+Mg+K), cmol+/kg 6,66 4,1 0,83 2,47 1,41 6,07 2,48 18,32 R = Sum/CEC (AmAc) 0,26 0,33 0,05 0,12 0,04 0,24 0,05 0,51 CEC hexaminnecobalt, cmol+/kg 6,8 3,5 3,5 4,3 2,6 2,9 6 18,1 Exchangeable Ca (Cohex), cmol+/kg 2,36

46、1,63 0,12 0,88 0,36 2,29 0,92 12,89 Exchangeable Mg (Cohex), cmol+/kg 1,74 0,64 0,03 0,24 0,29 0,26 0,63 2,89 Exchangeable K (Cohex), cmol+/kg 0,21 0,08 0,15 0,46 0,27 0,45 0,37 0,55 Exchangeable Na (Cohex), cmol+/kg 0,25 0,32 0,28 0,09 0,08 0,14 0,22 0,05 Exchangeable Al (Cohex), cmol+/kg 0,14 0,12

47、 0,41 0,11 1,63 0,58 3,37 0,07 Exchangeable H (Cohex), cmol+/kg 0,05 0,05 0,05 0,05 0,36 0,24 0,2 0,05 Sum (Ca+Na+Mg+K+Al+H), cmol+/kg 4,7 2,79 0,99 1,67 2,99 3,96 5,71 16,45 R = Sum/CEC (Cohex) 0,69 0,80 0,28 0,39 1,15 1,37 0,95 0,91 DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 15 Key X CEC AmAC,

48、 cmol+/kg Y CEC Cohex, cmol+/kg Figure A.4 Comparison of the hexamminecobalt trichloride method (Cohex) with the ammonium acetate method (AmAc) for the determination of CEC of some volcanic soils from Japan DIN EN ISO 23470:2011-09 EN ISO 23470:2011 (E) 16 Annex B (informative) Results of the interl

49、aboratory comparison An interlaboratory trial was organized in 2005 by ISO/TC 190/SC 3/WG 8 to test the procedures specified in this International Standard. For this interlaboratory trial, the determination of the CEC and exchangeable K, Na, Ca and Mg of four soils was carried out by 13 laboratories from Austria, Czech Republic, Germany, France, Korea, Netherlands, Poland, Spain, Sweden and the United Kingdom. The summary of the results of the interlaboratory trial is presented in Tables B.1 to