BS-EN-13270-2001.pdf

BRITISH STANDARD BS EN 13270:2001 Incorporating Corrigendum No. 1 Surface active agents Determination of the active matter content in alkyldimethylbetaines The European Standard EN 13270:2001 has the status of a British Standard ICS 71.100.40 ? Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 13270:2001 This British Standard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 June 2001 © BSI 8 January 2004 ISBN 0 580 37404 1 National foreword This British Standard is the official English language version of EN 13270:2001, including Corrigendum July 2002. The UK participation in its preparation was entrusted to Technical Committee CII/34, Methods of test for surface active agents, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Additional information Some textual errors were discovered when the English language version of EN 13270:2001 was adopted as the national standard. Some of the chemical names are not consistently presented and do not conform to IUPAC recommendations. These textual errors have been reported to CEN in a proposal to amend the text of the European Standard. Cross-references The British Standards which implement international or European publications 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 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 their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. 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 European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 10, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments 14889 Corrigendum No. 1 8 January 2004Correction to Clause 10.2 Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 13270 March 2001 ICS 71.100.40 Incorporating corrigendum July 2002 English version Surface active agents Determination of the active matter content in alkyldimethylbetaines Agents de surface Dosage de la teneur en matière active dans les alkyldiméthylbétaïnes Grenzflächenaktive Stoffe Bestimmung des Aktivgehalts in Alkyldimethylbetainen This European Standard was approved by CEN on 4 February 2001. 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 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 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, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13270:2001 E Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 2 EN 13270:2001 © BSI 8 January 2004 Contents Foreword 3 1 Scope.4 2 Normative references.4 3 Terms and definitions 4 4 Principle.4 5 Reagents4 6 Apparatus5 7 Sampling and preparation of the test sample .5 8 Procedure5 9 Calculation and expression of results5 10 Precision6 11 Test report.6 Annex A (informative) Ring test results7 Annex B (informative) Example for potentiometric titration parameters8 Annex C (informative) Typical titration curve of an alkyl dimethyl betaine and its first derivative9 Bibliography.10 Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 3 EN 13270:2001 © BSI 8 January 2004 Foreword This European Standard has been prepared by Technical Committee CEN/TC 276, Surface active agents, the Secretariat of which is held by AFNOR. 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 September 2001, and conflicting national standards shall be withdrawn at the latest by September 2001. Annexes A, B, and C are informative. According to the CEN/CENELEC 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, Ireland, Italy, Lithuania, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 4 EN 13270:2001 © BSI 8 January 2004 1 Scope This European Standard specifies a test method for the determination of up to 1 mmol of alkyl dimethyl betaine. Monochloroacetic acid, glycolic acid, strong acids and amines do not interfere. 2 Normative references This European Standard incorporates by 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 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 edition of the publication referred to applies (including amendments). EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696:1987). ISO 607, Surface active agents and detergents Methods of sample division. 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 active matter content content of alkyl dimethyl betaine which can be determined by this test method, expressed in grams per 100 g 4 Principle Alkyl dimethyl betaines are determined by alkalimetric titration with potentiometric indication of the end point. The sample is dissolved in isobutyl methyl ketone. Acidification with propanolic hydrochloric acid converts all the basic components into their protonated form. In isobutyl methyl ketone, the difference in acidity between the protonated betaine, the protonated amine, the monochloroacetic acid and glycolic acid, proves sufficient to determine the betaine separately from the compounds mentioned by titration with ethanolic potassium hydroxide standard volumetric solution. Carbon dioxide is removed by stripping out with nitrogen. 5 Reagents During the analysis use only reagents of recognized analytical grade and water complying with grade 3 as defined in EN ISO 3696. 5.1 Isobutyl methyl ketone. 5.2 Potassium hydroxide standard volumetric solution, c(KOH) = 0,1 mol/l in ethanol. 5.3 Hydrochloric acid, c(HCl) 0,1 mol/l in propan-2-ol. 5.4 Nitrogen, purity 99 % (m/m). Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 5 EN 13270:2001 © BSI 8 January 2004 6 Apparatus Ordinary laboratory apparatus and the following: 6.1 Potentiometric titrating apparatus, including a titrator with a combined glass/calomel electrode c(LiCl) = 3 mol/l in methanol, a piston burette of 20 ml capacity and a magnetic stirrer (titration parameters see annex B). 6.2 Analytical balance, accurate to 0,1 mg. 7 Sampling and preparation of the test sample Sample the material to be tested, in accordance with ISO 607. Gently melt solid and pasty samples on a water-bath at the lowest possible temperature (maximal 60 °C). 8 Procedure Weigh approximately 0,7 g of the sample to the nearest 0,1 mg into a 250 ml glass beaker. If the basicity of the sample exceeds 1,2 mmol, reduce the sample mass or increase the excess of hydrochloric acid (5.3) proportionately. NOTE It is essential to ensure that the sample is dissolved completely. No streakiness should be visible. Sodium chloride precipitates on addition of hydrochloric acid solution, but this does not interfere with the determination. Dissolve in 15 ml ± 0,5 ml hydrochloric acid (5.3) and stir at least 10 min after the addition. Add 150 ml isobutyl methyl ketone (5.1) and stir for further 5 min after the addition. Pass in nitrogen gas (5.4) for 5 min. NOTE It is advisable to pass in the nitrogen by means of a disposable glass pipette. Allow the tip of the pipette to dip approximately 2 cm into the sample solution and adjust the flow of nitrogen so that 2 to 3 bubbles emerge per second. Immerse the electrode, stir and titrate with the ethanolic potassium hydroxide standard volumetric solution (5.2) to the second inflexion point (see Figure C.1). 9 Calculation and expression of results Calculate the content of alkyl dimethyl betaine, w, expressed in grams per 100 g, using the following equation (1): 0001 100 12 )( × ××× = m M C V - V w (1) where: V1 is the volume consumed of ethanolic potassium hydroxide standard volumetric solution (5.2) to the first inflexion point, in millilitres; V2 is the volume consumed of ethanolic potassium hydroxide standard volumetric solution (5.2) to the second inflexion point, in millilitres; Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 6 EN 13270:2001 © BSI 8 January 2004 C is the concentration of the ethanolic potassium hydroxide standard volumetric solution, in moles per litre; M is the molar mass of the alkyl dimethyl betaine, in grams per mole; m is the mass of the sample, in grams. The content of alkyldimethylbetaine, w, shall be given to two decimal places. 10 Precision 10.1 Repeatability limit The absolute difference between two independent single test results, obtained using the same method on identical test material in the same laboratory by the same operator using the same equipment within a short interval of time, will not exceed the repeatability limit, r, in more than 5 % of cases. According to the ring test results given in annex A, the repeatability limit, r, shall be less than or equal to 0,37 g/100 g for an active matter content of approximately 32 g/100 g. 10.2 Reproducibility limit The absolute difference between two independent single test results, obtained using the same method on identical test material in different laboratories by different operators using different equipment, will not exceed the reproducibility limit, R, in more than 5 % of cases. According to the ring test results given in annex A, the reproducibility limit, R, shall be less than or equal to 0,75 g/100 g for an active matter content of approximately 32 g/100 g. 11 Test report The test report shall include the following information: a) all information necessary for the complete identification of the sample; b) a reference to this European Standard; c) the results; d) any particular points observed in the course of the test; e) details of any operations not specified in this European Standard, and any operations regarded as optional, as well as any incidents likely to have affected the results. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 7 EN 13270:2001 © BSI 8 January 2004 Annex A (informative) Ring test results The statistical data given in Table A.1 were obtained by a ring test carried out in 1995 by the German committee for analysis of surfactants, “Gemeinschalftsausschuß für die Analytik von Tensiden (GAT)”, using commercially available samples of alkyl dimethyl betaine. The evaluation was performed in accordance with ISO 5725-2. Table A.1 Designation Precision data Number of laboratories participating: 8 Number of laboratories not eliminated: Number of individual values of all laboratories: Mean value, w (g/100 g): Repeatability standard deviation sr (g/100 g): Repeatability r: r = 2,8 x sr (g/100 g): Repeatability coefficient of variation, vr: vI = (sr /w)100 in %: Reproducibility standard deviation sR (g/100 g): Reproducibility limit, R: R = 2,8 x sR (g/100 g): 6 18 32,0 0,13 0,37 0,4 0,27 0,75 Reproducibility coefficient of variation, vR: vR = ( sR/w) 100 in % 0,8 Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 8 EN 13270:2001 © BSI 8 January 2004 Annex B (informative) Example for potentiometric titration parameters The following potentiometric titration parameters refer to a Metrohm 670 titroprocessor and can serve as a guideline (see Table B.1). Table B.1 1 SBOX 14 2 MEAS 1 2a QUANTITY U 2b DRIFT/min 100 mV 2c M. DELAY 19 s 3 DYNT 1 3a MPT. DENSITY 4 3b DOS. RATE/min 2 000 ml 3c f. VRESOL 0,02 % 4 TSTOP 4a N.EPs 8 4b VOLUME 25 000 ml 4c M. VALUE off 5 END NOTE The designations of the parameters correspond to those given by the Metrohm Titroprocessor 670. Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 9 EN 13270:2001 © BSI 8 January 2004 Annex C (informative) Typical titration curve of an alkyl dimethyl betaine and its first derivative Key 1) Voltage, in millivolts 2) Volume consumed of ethanolic potassium hydroxide standard volumetric solution, in millilitres 3) First inflexion point 4) Second inflexion point Figure C.1 Typical titration curve (A) of an alkyl dimethyl betaine and its first derivative (B) Licensed Copy: sheffieldun sheffieldun, na, Mon Oct 30 04:57:06 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 10 EN 13270:2001 © BSI 8 January 2004 Bibliography ISO 5725-2:1994, Accuracy (trueness and precision) of measurement methods and results Part 2 :