SIST EN 12945:2008

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Liming materials - Determination of neutralizing value - Titrimetric methodsLWULPHWULMVNHPHWRGHAmendements minéraux basiques - Détermination de la valeur neutralisante - Méthodes par titrimétrieCalcium-/Magnesium-Bodenverbesserungsmittel - Bestimmung des Neutralisationswertes - Titrimetrische VerfahrenTa slovenski standard je istoveten z:EN 12945:2008SIST EN 12945:2008en,fr,de65.080ICS:SIST EN 12945:20031DGRPHãþDSLOVENSKI
STANDARDSIST EN 12945:200801-april-2008







EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 12945February 2008ICS 65.080Supersedes EN 12945:2002
English VersionLiming materials - Determination of neutralizing value -Titrimetric methodsAmendements minéraux basiques - Détermination de lavaleur neutralisante - Méthodes par titrimétrieCalcium-/Magnesium-Bodenverbesserungsmittel -Bestimmung des Neutralisationswertes - TitrimetrischeVerfahrenThis European Standard was approved by CEN on 28 December 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, 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 STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12945:2008: E



EN 12945:2008 (E) 2 Contents page Foreword.3 Introduction.4 1 Scope.4 2 Normative references.4 3 Terms and definitions.4 4 Principle.4 5 Reagents.5 6 Apparatus.5 7 Sampling.5 8 Procedure.6 9 Expression of results for both Method A and Method B.7 10 Precision.7 11 Test report.8 Annex A (informative)
Results of an inter-laboratory trial to determine the neutralizing value.9 Bibliography.10



EN 12945:2008 (E) 3 Foreword This document (EN 12945:2008) 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 August 2008, and conflicting national standards shall be withdrawn at the latest by August 2008. 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 12945:2002. 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, Cyprus, Czech Republic, 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 the United Kingdom.



EN 12945:2008 (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. 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 and liming materials with more than 3 % P2O5. Method B is applicable to all liming materials except products with more than 3 % mass fraction P2O5, and calcined and slaked products of carbonate origin. NOTE The methods described in ISO 6598 and ISO 7497 can be used for the determination of P2O5 content (see [2] and [3]). 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 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 3696:1987) 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.



EN 12945:2008 (E) 5 5 Reagents 5.1 General During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and water conforming to grade 3 in accordance with EN ISO 3696. NOTE Commercially available solutions can be used. 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 indicator. Apply the appropriate correction factor in the calculation of the results (see Clause 9). 5.3 Sodium hydroxide standard solution, c(Na
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