1、December 2016 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).ICS 67.200.10!%b6“2596319www.din.de
2、DIN EN 14112Fat and oil derivatives Fatty Acid Methyl Esters (FAME) Determination of oxidation stability (accelerated oxidation test);English version EN 14112:2016,English translation of DIN EN 14112:2016-12Erzeugnisse aus pflanzlichen und tierischen Fetten und len FettsureMethylester (FAME) Bestimm
3、ung der Oxidationsstabilitt (beschleunigte Oxidationsprfung);Englische Fassung EN 14112:2016,Englische bersetzung von DIN EN 14112:2016-12Produits drivs des corps gras Esters mthyliques dacides gras (EMAG) Dtermination de la stabilit loxydation (Essai doxydation acclre);Version anglaise EN 14112:201
4、6,Traduction anglaise de DIN EN 14112:2016-12SupersedesDIN EN 14112:200310www.beuth.deDocument comprises 22 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.12.16 DIN EN 14112:2016-12 2 A comma is used as the decimal marker. Nat
5、ional foreword This document (EN 14112:2016) has been prepared by Technical Committee CEN/TC 307 “Oil seeds, vegetable and animal fats and oils and their by-products Methods of sampling and analysis” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was DIN-Normen
6、ausschuss Materialprfung (DIN Standards Committee Materials Testing), Working Committee NA 062-06-32-01 UA Prfung von FAME of the Fachausschuss Minerall- und Brennstoffnormung (FAM). Amendments This standard differs from DIN EN 14112:2003-10 as follows: a) the scope of the method has been limited to
7、 a maximum induction period of 48 h, reflecting the precision range of the method; b) a potential alteration of the induction period in the presence of cetane enhancers has been indicated; c) the standard has been editorially revised in order to clarify the test procedure; d) Clause 2 “Normative ref
8、erences” has been added; e) Clause 11 “Expression of results” has been added; f) background information on the method has been added as Annex A. Previous editions DIN EN 14112: 2003-10 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 14112 September 2016 ICS 67.200.10 Supersedes EN 14112:2003Eng
9、lish Version Fat and oil derivatives - Fatty Acid Methyl Esters (FAME) -Determination of oxidation stability (accelerated oxidation test) Produits drivs des corps gras - Esters mthyliques dacides gras (EMAG) - Dtermination de la stabilit loxydation (Essai doxydation acclre) Erzeugnisse aus pflanzlic
10、hen und tierischen Fetten und len - Fettsure-Methylester (FAME) - Bestimmung der Oxidationsbestndigkeit (Beschleunigte Oxydationsprfung) This European Standard was approved by CEN on 8 July 2016. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions
11、 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 t
12、hree 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
13、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
14、, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved wor
15、ldwide for CEN national Members. Ref. No. EN 14112:2016 EEN 14112:2016 (E) 2 Contents Page European foreword . 3 Introduction 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Principle . 5 5 Reagents and materials . 6 6 Apparatus . 6 7 Sampling . 8 8 Preparation of measurement . 9
16、8.1 Preparation of test sample 9 8.2 Preparation of apparatus . 9 8.2.1 Cleaning procedure 9 8.2.2 Temperature correction . 9 9 Measurement . 10 10 Calculation and Evaluation . 13 10.1 Automatic evaluation 13 10.2 Manual evaluation . 15 11 Expression of results . 16 12 Precision 16 12.1 General . 16
17、 12.2 Repeatability, r 16 12.3 Reproducibility, R 16 13 Test report 16 Annex A (informative) Background of the method . 18 Annex B (informative) Results of an Interlaboratory Study 19 Bibliography . 20 DIN EN 14112:2016-12 EN 14112:2016 (E) 3 European foreword This document (EN 14112:2016) has been
18、prepared by Technical Committee CEN/TC 307 “Oilseeds, vegetable and animal fats and oils and their by-products - Methods of sampling and analysis”, 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 identica
19、l text or by endorsement, at the latest by March 2017, and conflicting national standards shall be withdrawn at the latest by March 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identi
20、fying any or all such patent rights This document supersedes EN 14112:2003. Significant changes between this document and EN 14112:2003 are: a) the limitation of the scope of the method to a maximum induction period of 48 h, reflecting the precision range of the method; b) indication of a potential
21、alteration of the induction period in the presence of cetane enhancers; c) editorial changes in order to clarify the test procedure; d) addition of Clause 2 Normative references; e) addition of Clause 11 Expression of results; f) background information on the method added as Annex A. According to th
22、e CEN-CENELEC Internal Regulations, the national standards organisations 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, H
23、ungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 14112:2016-12 EN 14112:2016 (E) 4 Introduction This document is based on EN 14112:2003, which w
24、as specifically adapted for the determination of oxidation stability of fatty acid methyl esters (FAME). This method had been developed under CEN/TC 307 (Fats and oils). The modifications as given in this document address the field experience with this method made since its introduction as a standar
25、d test method. Editorial changes are made in order to specify some aspects of the test. Additionally, the cleaning procedure is modified based on field experience. DIN EN 14112:2016-12 EN 14112:2016 (E) 5 1 Scope This European Standard specifies a method for the determination of the oxidation stabil
26、ity of fatty acid methyl esters (FAME) at 110 C, by means of measuring the induction period up to 48 h. NOTE 1 EN 15751 1 describes a similar test method for oxidation stability determination of pure fatty acid methyl esters and of blends of FAME with petroleum-based diesel containing 2 % (V/V) of F
27、AME at minimum. NOTE 2 The precision statement of this test method was determined in a Round Robin exercise with induction periods up to 8,5 h, thus covering the limit value in EN 14214. Results from precision studies on EN 15751 indicate that the precision statement is valid for induction periods u
28、p to 48 h but not for higher values. NOTE 3 Limited studies on EN 15751 with EHN (2-ethyl hexyl nitrate) on FAME blends indicated that the stability is reduced to an extent which is within the reproducibility of the test method. It is likely that the oxidation stability of pure FAMEs is also reduced
29、 in the presence of EHN when EN 14112 is used for testing. 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 lat
30、est edition of the referenced document (including any amendments) applies. EN ISO 3170, Petroleum liquids - Manual sampling (ISO 3170) EN ISO 3171, Petroleum liquids - Automatic pipeline sampling (ISO 3171) 3 Terms and definitions For the purposes of this document, the following terms and definition
31、s apply. 3.1 induction period time which passes between the moment when the measurement is started and the moment when the formation of oxidation products begins to increase rapidly 3.2 oxidation stability induction period determined according to the procedure specified in this European Standard, ex
32、pressed in hours 4 Principle A stream of purified (dried) air is passed through the sample which has been heated to the target temperature which is 110 C in the usual application of the method. Volatile compounds are formed during the oxidation process. They are, passed together with the air into a
33、flask containing demineralized or distilled water, equipped with a conductivity electrode. The electrode is connected to a measuring and recording device. It indicates the end of the induction period by rapid increase of the conductivity due to the dissociation of volatile carboxylic acids produced
34、during the oxidation process and absorbed in the water. For more details on the background of the method see Annex A. DIN EN 14112:2016-12 EN 14112:2016 (E) 6 5 Reagents and materials Use only reagents of analytical grade and distilled or demineralized water. 5.1 Ternary solvent mixture, consisting
35、of methanol/toluene/acetone 1:1:1 (by volume). 5.2 Alkaline laboratory glass cleaning solution. 5.3 2-Propanol. 6 Apparatus Usual laboratory equipment and glassware, together with the following: 6.1 Device for the determination of oxidation stability, comprising the following parts (see Figures 1 an
36、d 2)1). 6.1.1 Air filter, comprising a tube fitted with filter paper at the ends and filled with a molecular sieve (6.6), connected to the suction end of a pump. 6.1.2 Gas membrane pump, with an adjustable flow rate of (10 1,0) l/h. 6.1.3 Reaction vessels of borosilicate glass, provided with a seali
37、ng cap. The sealing cap shall be fitted with a gas inlet and outlet tube. 6.1.4 Closed measurement cells, of approximately 150 ml capacity, with an air inlet tube extending to the bottom inside of the vessel. The cell shall have ventilation holes at the top. 6.1.5 Electrodes, for measuring conductiv
38、ity within a range of 0 S/cm to 300 S/cm aligned with the dimensions of the measurement cell (6.1.4). 6.1.6 Measuring and recording apparatus, comprising: a) an amplifier; and b) a recorder registering the signal of each of the electrodes (6.1.5). 6.1.7 Thyristor and contact thermometer graduated in
39、 0,1 C or Pt 100 element to measure the block temperature, with attachments for relay connection and an adjustable heating element; temperature scale 0 C to 150 C. 1) Rancimat is the trade name of a product supplied by Metrohm AG, Herisau, Switzerland; OSI is the trade name of a product supplied by
40、Omnion Inc., Rockland, Massachusetts, USA. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN or CENELEC of the products named. Equivalent products may be used if they can be shown to lead to the same results. DIN EN 14112:2
41、016-12 EN 14112:2016 (E) 7 6.1.8 Heating block, made of cast aluminium, adjustable to a temperature up to (150 0,1) C. The block shall be provided with holes for the reaction vessels (6.1.3) and an aperture for the contact thermometer (6.1.7). Alternatively a heating bath may be used, filled with oi
42、l suitable for temperatures up to 150 C, and adjustable to the nearest 0,1 C. 6.2 Certified and calibrated thermometer or Pt100 element, with a temperature range up to 150 C, graduated in 0,1 C. Key 1 air filter (6.1.1) 5 electrode (6.1.5) 2 gas membrane pump with flow rate control (6.1.2) 6 measuri
43、ng and recording apparatus (6.1.6) 3 reaction vessel (6.1.3) 7 thyristor and contact thermometer (6.1.7) 4 measurement cell (6.1.4) 8 heating block (6.1.8) Figure 1 Apparatus DIN EN 14112:2016-12 EN 14112:2016 (E) 8 Dimensions in mm Key 1 measuring vessel 5 sample 2 electrode 6 heating block 3 disti
44、lled/demineralized water 7 air inlet 4 reaction vessel Figure 2 Diagrammatic representation of heating block, reaction vessel and measurement cell 6.3 Measuring pipettes and/or measuring cylinders. 6.4 Oven, adjustable to a temperature up to (150 3) C. 6.5 Connecting hoses, flexible and made of iner
45、t material polytetrafluoroethylene (PTFE) or silicone. 6.6 Molecular sieve, with moisture indicator, pore size 0,3 nm, dried in an oven set at 150 C and cooled down to room temperature in a desiccator before use. 6.7 Balance, capable of weighing with an accuracy of 0,1 g or less. 7 Sampling Unless o
46、therwise specified, sampling shall be conducted according to EN ISO 3170 or EN ISO 3171 and/or in accordance with the requirements of national standards or regulations for the sampling. It is important that the laboratory receives a sample which is truly representative and has not been damaged or ch
47、anged during transport and storage. Store the sample in the dark at about 4 C and measure it as soon as possible after receipt. DIN EN 14112:2016-12 EN 14112:2016 (E) 9 8 Preparation of measurement 8.1 Preparation of test sample In order to ensure a consistent test condition, all samples shall be tr
48、eated in the way described below: take the required quantity from the centre of the carefully homogenized sample using a pipette; analyse the samples immediately after sample preparation. 8.2 Preparation of apparatus 8.2.1 Cleaning procedure The use of new disposable reaction vessels, air inlet tube
49、s and connecting hoses is recommended in order to save the cleaning procedure. Sealing caps, measuring cells and electrodes shall be cleaned with 2-Propanol in order to remove organic residues. The connecting hoses should also be washed in the same manner if not replaced. Rinse with tap water and finally with demineralized or distilled water. Dry the cleaned parts in an oven at 80 C for at least 2 h. The temperature
