1、BSI Standards PublicationPD CEN/TR 16885:2015Liquid petroleum products Investigation on test methodfor measurement of theoxidation stability of diesel anddiesel/FAME blends by AcidNumber after ageingPD CEN/TR 16885:2015 PUBLISHED DOCUMENTNational forewordThis Published Document is the UK implementat
2、ion of CEN/TR16885:2015.The UK participation in its preparation was entrusted to TechnicalCommittee PTI/13, Petroleum Testing and Terminology.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessar
3、yprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 90120 1ICS 75.160.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document was pu
4、blished under the authority of theStandards Policy and Strategy Committee on 30 September 2015.Amendments issued since publicationDate Text affectedPD CEN/TR 16885:2015TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16885 September 2015 ICS 75.160.20 English Version Liquid petroleum pr
5、oducts - Investigation on test method for measurement of the oxidation stability of diesel and diesel/FAME blends by Acid Number after ageing Produits ptroliers liquides - Recherche de la dtermination de la stabilit loxydation du gazole et des mlanges gazole/EMAG par lindice dacide aprs vieillisseme
6、nt Flssige Minerall-Erzeugnisse - Bericht ber die Bestimmung der Oxidationsstabilitt von Diesel und Diesel/FAME-Mischungen durch Bestimmung der Surezahl nach Verlterung This Technical Report was approved by CEN on 17 August 2015. It has been drawn up by the Technical Committee CEN/TC 19. CEN members
7、 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,
8、 Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form an
9、d by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16885:2015 EPD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 2 Contents Page European foreword 3 1 Scope . 4 2 Context and creation of a dedicated subgroup 4 3 Participants in the work 5 4 Meetings of the subgroup Acid No.“ . 5 5 M
10、ain steps of the work item study . 6 5.1 Creation of the NWI . 6 5.2 Test method used . 6 5.3 First Round Robin Test 7 5.4 Improvement of the test method 7 5.5 Pass/fail methodology 8 5.6 Second Round Robin Test . 9 6 Conclusions . 11 7 Acid number determination method available for lab use 11 8 Ack
11、nowledgements 11 Annex A (informative) Test method transcription 12 Annex B (normative) Round Robin Results 20 B.1 October 2010 results . 20 B.2 2012/2013 RRT . 22 Annex C (normative) Pass-/Fail discriminant analysis 25 Bibliography 31 PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 3 European foreword Th
12、is document (CEN/TR 16885:2015) has been prepared by Technical Committee CEN/TC 19 “Gaseous and liquid fuels, lubricants and related products of petroleum, synthetic and biological origin”, the secretariat of which is held by NEN. Attention is drawn to the possibility that some of the elements of th
13、is 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. PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 4 1 Scope This Technical Report describes the investigation into the development of a standard test method to det
14、ermine oxidation stability of diesel fuel and fatty acid methyl ester (FAME) blends in diesel by the use of determining the acid number after ageing at elevated temperature. It provides conclusions following this work that have been discussed by CEN. The result thereof is that no European Standard h
15、as been developed. 2 Context and creation of a dedicated subgroup In case of poor diesel or biodiesel quality, ageing of the fuel in the fuel system under high pressure and temperature (recirculation of fuel, high injector temperature, long storage in the vehicle fuel tank) may cause various car pro
16、blems due to the formation of acidity through oxidation (i.e. deposit of sediments, deposit of lacquer, corrosion, lube oil deterioration). Acidity of the fuel is therefore considered as a relevant parameter to evaluate oxidation stability of the Diesel fuel. Test methods based on the measurement of
17、 the acid number (AN) after an ageing step were studied. An ageing test temperature of 115 C which is significantly higher than the test temperature of 95 C applied in EN ISO 12205 1 has been chosen because it better discriminates fuels oxidation stability. Additionally, it is closer to the temperat
18、ure range prevailing in fuel systems of current and future engine technologies (i.e. common rail systems). Customer complaints related to fuel degradation linked to oxidation stability in France are shown in Figure 1. Figure 1 Customer complaints linked to fuel degradation in France PD CEN/TR 16885:
19、2015CEN/TR 16885:2015 (E) 5 A test method based on the change of the acid no. of a fuel during ageing, Delta AN, was evaluated in CEN/TC 19/JWG1 FAME Test methods in 2008. In the Delta AN method, the fuel is aged at 115 C for 16 h by passing a stream of oxygen through the fuel using the oxidation ce
20、ll of EN ISO 12205. The acid number of the fuel before ageing is subtracted from the acid number of the aged fuel. The results of Round Robin tests made on the Delta AN method led to the conclusion that the Delta AN test method, although discriminative, exhibits a precision not enough robust ; this
21、test method needed some analytical improvements. A draft report about the test results applying the Delta AN method performed in 2008 was presented to CEN/TC 19/JWG1 in January, 2011. Further work concerning the improvement of the Delta AN test method was carried out in France in 2009. A new test me
22、thod based on the measurement of the acid number of the fuel after ageing was developed. Based on the results of a cross check test, it was decided at the JWG1 meeting on September 4, 2009, that additional work would be necessary concerning the robustness and precision of the new method. As such wor
23、k being not covered by the CEN/TC 19 mandate to JWG1, it was proposed that experts continue the improvement work and issue a proposal for a NWI to WG 24. Based on the results of the work of the French experts the continuation of the work was accepted by WG24 in March 2010. JWG1 started the work, cre
24、ating a dedicated subgroup for this preliminary new work item (PNWI). 3 Participants in the work Several European experts were active within this project, represented by one or more member(s) participating in the meetings. The memberships are listed in Table 1. Table 1 Members of the Subgroup Acid N
25、o.“ Company Country Members PSA France P. Jestin TOTAL France S. Duperrier; P. Manuelli; P. Pestiaux; A. Vincent; A. Gandubert SHELL Germany M. Schmidt Deutsche BP Germany W. Strojek Neste Oil Finland M. Kuronen IFPEN France L. Pidol OMV Austria W. Koliander ADM Germany J. Groos; J. Fischer ASG Germ
26、any T. Wilharm Metrohm Switzerland C. Haider; U. Loyall SGS Germany, France M. Kulikowski; D. Juillet 4 Meetings of the subgroup Acid No.“ The members of the group have been working on the assessment of the oxidation stability of diesel and diesel/FAME blends by determination of the acid value after
27、 ageing from beginning of 2010 to mid-2014. The meetings are listed in Table 2. This work have been reported and discussed within JWG1 at each session. The main orientations and action plans have systematically been validated by JWG1. PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 6 Table 2 Meetings of t
28、he Subgroup Acid No.“ Meeting Date and location Meeting 1 April 27, 2010 Conference call Meeting 2 July 07, 2010 Meeting 3 January 14, 2011 Meeting 4 May 24, 2011 PSA Peugeot Citron Paris Call conference July 25, 2011 Conference call Meeting 5 September 02, 2011 IFPEN Rueil Meeting 6 March 22, 2012
29、PSA Peugeot Citron La Garenne Colombes Meeting 7 November 13, 2013 TOTAL Paris La Dfense 5 Main steps of the work item study 5.1 Creation of the NWI The first meeting of the group took place in April, 2010. The scope was presented to the members: the objective was to improve the precision of the new
30、 acid number test method applicable to diesel fuels from B0 to B10. In that context, some adjustments were made on the test method protocol and it was decided to run first a cross-check test. Necessary improvements based on the outcome of the study should be implemented to the method. A Round Robin
31、test should finally be conducted in order to develop the precision of the method. 5.2 Test method used The method used has been developed to be applicable to diesel fuels from B0 to B10. The main analytical parameters are listed hereafter and the full description of the test method is given in Annex
32、 A. Sample amount: (10 0,2) g; Heating bath temperature: (115 0,2) C1; Oxygen rate: (1 0,1) L/h; Running time for fuel oxidation: 16 h 5 min; Maximal time between the end of oxidation step and the AN measurement: 4 h. 1The fuel was aged either in an oil bath or an heating bath as applied in the Ranc
33、imat equipment PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 7 5.3 First Round Robin Test A RT was run in October, 2010 to assess the precision of the proposed new AN method on both colorimetric and potentiometric determination of the AN. Nine samples were used for the RRT: 3 B0, 4 B7 and 2 B10. Samples
34、 were representative for the European Market, some containing cetane improver (content between 100 and 1000 ppm), CFPP additives and/or lubricity additives. Thirteen labs out of fourteen participants have returned their results on time: ten labs have performed colorimetric determination (oil bath an
35、d Rancimat bath according to EN 15751 2) and eleven labs have performed potentiometric determination (oil bath and Rancimat bath according to EN 15751). The results of this RRT are given in Annex B. The RRT results led to the following comments: Even if there was a discrimination between “good” and
36、“bad” products, results were worse than expected, in particular for the potentiometric version. When the dispersion of results with the potentiometric method was discussed, all participants agreed that experimental parameters were perhaps not optimized and that it was necessary to work on it (electr
37、ode system, solvent, dynamic titration, etc.). “Home-made” diesels, meaning diesels formulated by blending “good” and “bad” B0 or B7 in order to reach certain AN target, seemed to have a strange behaviour. Even if the formulated products seemed to be homogeneous, the results obtained by the labs wer
38、e really different and the statistical distribution of results indicated strong issues. There were some difficulties of being more precise on very good samples (AN 59 mV; for any basic solution it is 59 mV. 10 Result report Report the acid number of the aged sample in mg KOH/g rounded to the nearest
39、 0,01. Appendix Cleaning procedure for oxidation cells The use of new glass tubes (1) and oxygen delivery tubes (2) is recommended in order to save the cleaning procedure. Always wash the plastic parts (tube caps (3), connectors (5), etc.) with 2-propanol in order to remove organic residues. Rinse w
40、ith tap water and finally with demineralised or distilled water. Dry them in an oven for at least 2 h at 80 C. If not replaced, wash the glass tubes (1) and the oxygen delivery tube (2) at least three times with trisolvent mixture3in order to remove residual fuel and adherent ageing organic residues
41、. The last solvent portion should be colourless. Rinse with 2-Propanol and tap water. Put the delivery tube into the glass tube and fill completely with an aqueous alkaline laboratory cleaning solution. Store the glass tubes and the oxygen delivery tubes at room temperature over night. Rinse the gla
42、ss tubes and the oxygen delivery tubes thoroughly with tap water and finally with demineralised or distilled water. Dry them in an oven for at least 2 h at 110 C. 3Trisolvent mixture, consisting of methanol/toluene/acetone 1:1:1 (by volume). PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 20 Annex B (norm
43、ative) Round Robin Results B.1 October 2010 results The first assessment results are given below. PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 21 PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 22 B.2 2012/2013 RRT Seven laboratories provided full sets of results, meaning results on both Part 1 and Part 2. T
44、he statistical processing has been done on those seven full sets of data. Statistical evaluation of the results was performed by the CEN/TC 19/WG 36 according to the methodology indicated in EN ISO 42594. Both linear and logarithmic models were used to evaluate the repeatability and reproducibility.
45、 Results are given in Figure B.1 and Table B.1 for linear treatment and in Figure B.2 and Table B.2 for log treatment. For each sample, the following data are detailed: 1) the number of participating / valid labs, 2) the mean value, 3) the repeatability (r) and reproducibility (R) including the degr
46、ees of freedom (for R only), 4) the Anderson Darling Criterium (“AD“), which can be used as a quick numeric indicator for the quality of the normal distribution (values below 1 are usually considered as satisfactory), 5) the fulfilment of the “2R” rule: is 2Rmean ? 0.001.002.003.004.005.006.007.008.
47、009.0001 02 03 04 05 06 07LabsABCDEFGHIJKLMNOPQRSFigure B.1 AN values measured by the participants on the 19 samples PD CEN/TR 16885:2015CEN/TR 16885:2015 (E) 23 Table B.1 EN ISO 4259 statistical processing of the data by applying the linear model LAB/SAMPLE A B C D E F G H I1 + 0.02 0.02 + 2.55 3.2
48、4 + 1.04 1.29 + 0.99 1.07 + 0 0.06 + 0.01 0.04 + 0 0 + 0.32 0.45 + 0.06 0.072 + 0.04 0.05 + 3.3 3.42 + 1.79 2.19 + 1.87 1.62 + 0.01 0 + 0 0 + 0.04 0.03 + 0.44 0.52 + 0.01 0.013 + 0.07 0.08 + 2.71 2.76 + 1.92 1.91 + 2.07 1.86 + 0.04 0.04 + 0.04 0.04 + 0.04 0.05 + 0.55 0.53 + 0.02 0.024 + 0.11 0.25 +
49、3.18 3.45 + 1.99 2.02 + 2.02 2 + 0.02 0.01 + 0.06 0.16 + 0.02 0.02 + 0.86 0.7 + 0.03 0.045 + 0.03 0.02 + 3.23 3.05 + 1.86 2.02 + 1.41 1.44 + 0.01 0.02 + 0.01 0.01 + 0.03 0.02 + 0.57 0.4 + 0.04 0.036 + 0.15 0.15 + 3.12 4.06 C 2.9 5.69 + 2.29 3.28 + 0.08 0.34 + 0.09 0.14 + 0.16 0.22 + 0.89 1.27 + 0.07 0.137 + 0.07 0.06 + 2.64 2.8 + 1.2 1.47 + 0.98 1.08 + 0.02 0.02 + 0.02 0.03 + 0.03 0.03 + 0.45 0.42 + 0.02 0.02SAMPLE A B C D E F G H ILabs / Valid Labs (7) 7 (7) 7 (7) 6 (7) 7 (7) 7 (7) 7 (7) 7 (7) 7 (7) 7Mea
