SIST EN 12945:2014

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.LWULPHWULMVNHPHWRGHCalcium-/Magnesium-Bodenverbesserungsmittel - Bestimmung des Neutralisationswertes - Titrimetrische VerfahrenAmendements minéraux basiques - Détermination de la valeur neutralisante - Méthodes par titrimétrieLiming materials - Determination of neutralizing value - Titrimetric methods65.080GnojilaFertilizersICS:Ta slovenski standard je istoveten z:EN 12945:2014SIST EN 12945:2014en,fr,de01-julij-2014SIST EN 12945:2014SLOVENSKI
STANDARDSIST EN 12945:2008/AC:2009SIST EN 12945:20081DGRPHãþD



SIST EN 12945:2014



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 12945
April 2014 ICS 65.080 Supersedes EN 12945:2008English Version
Liming materials - Determination of neutralizing value - Titrimetric methods
Amendements minéraux basiques - Détermination de la valeur neutralisante - Méthodes par titrimétrie
Kalkdünger - Bestimmung des Neutralisationswertes - Titrimetrische Verfahren This European Standard was approved by CEN on 8 February 2014.
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 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 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, Denmark, Estonia, Finland, Former Yugoslav 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.
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B-1000 Brussels © 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12945:2014 ESIST EN 12945:2014



EN 12945:2014 (E) 2 Contents Page Foreword .3 Introduction .4 1 Scope .5 2 Normative references .5 3 Terms and definitions .5 4 Principle .5 5 Reagents .5 6 Apparatus .6 7 Sampling .6 8 Procedure .6 9 Calculation and expression of results for method A and method B .8 10 Precision .8 11 Test report .9 Annex A (informative) Results of an inter-laboratory trial to determine the neutralizing value . 10 Bibliography . 11
SIST EN 12945:2014



EN 12945:2014 (E) 3 Foreword This document (EN 12945:2014) 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 of an identical text or by endorsement, at the latest by October 2014 and conflicting national standards shall be withdrawn at the latest by October 2014. 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 supersedes EN 12945:2008. The following changes have been made to the former edition: a) scope modified taking into account that method A is not applicable to liming materials with more than 3 % P2O5 and that method B is applicable to all liming materials; b) reference to EN 14984 added to the scope and the Bibliography; c) 9.2 amended by addition of an instruction concerning the use of correction factors; d) optional requirement concerning correction factors added to Clause 11 Test report; e) corrigendum EN 12945:2008/AC:2009 included; f) editorially revised. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following 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, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 12945:2014



EN 12945:2014 (E) 4 Introduction Two different procedures are described (method A and method B) because the titration to pH 7,0 is not applicable to silicate liming materials due to the precipitation of compounds at this pH value. In method B the turning point at pH 4,8 on the titration curve is taken as the end-point of the titration. For carbonaceous liming materials the difference in the consumption of sodium hydroxide solution for back titration between the titration end-points of pH 4,8 and pH 7,0 is negligible. SIST EN 12945:2014



EN 12945:2014 (E) 5 1 Scope This European Standard specifies two methods for the determination of the neutralizing value (NV) of liming materials. Method A is applicable to all liming materials except silicate liming materials. Method B is applicable to all liming materials. Both methods do not correctly take into account the potential neutralizing value of material containing more than 3 % P2O5. For a more accurate agronomic assessment of products containing more than 3 % P2O5 determine the liming efficiency according to EN 14984. NOTE The methods described in ISO 6598 [1] and ISO 7497 [2] can be used for the determination of P2O5 content. Further information on P analyses is given in [3] and [4]. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document 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: Sample preparation EN 12944-3:2001, Fertilizers and liming materials —Vocabulary — Part 3: Terms relating to liming materials EN ISO 3696, Water for analytical laboratory use — Specification and test methods (ISO 3696) ISO 3310-1, Test sieves — Technical requirements and testing — Part 1: Test sieves of metal wire cloth 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 12944-3:2001 apply. 4 Principle Dissolution of the sample in a specified quantity of hydrochloric acid standard solution. Determination of the excess acid by back titration with a sodium hydroxide standard solution. 5 Reagents During the analysis, unless otherwise stated, use only reagents of recognised analytical grade. NOTE Commercially available solutions can be used. 5.1 Water, according to EN ISO 3696, grade 3. 5.2 Hydrochloric acid standard solution, c(HCl) = 0,5 mol/l. Determine the exact concentration of the solution by titration with sodium hydroxide standard solution (5.3) using phenolphthalein solution (5.4) as in
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