This document specifies a calculation procedure for the determination of iodine value (“CIV” - “calculated iodine value”) of fatty acid methyl esters (FAME) to be used either as automotive fuel for diesel engines as specified in EN 14214 [2] or heating fuel or as an extender for automotive fuel for diesel engines as specified in EN 590 [3]. This procedure does not apply to Ethyl esters or esters made from fish oil and mixtures thereof.
The calculation procedure is applicable to methyl esters between C6 and C24:1. The calculation procedure uses as data entry the results from the gas chromatography determination (GC) according to EN 14103 of individual fatty acid methyl esters and is based on AOCS recommended practice Cd 1c - 85 for the determination of the iodine value of edible oil from its fatty acid composition. It is important to recognize that the latest version of EN 14103 is intended to be used for the determination of individual FAME components.
NOTE 1 Experience from the field and from several precision evaluation campaigns in Germany and elsewhere indicates that the results of the determination of iodine value by the calculation specified here are very close to results obtained by titration with Wijs solvent according to EN 14111 [1]. Observed small differences were always found to be smaller than the reproducibility published in the actual EN 14111.
For informative purposes only, but not for cases of dispute, EN 14331 [4] can also be used to extract the FAME contents from FAME containing diesel fuels (like B5, B7, B30, etc.) and to use the contents of the individual FAME components from this method as data entry for the calculation specified in this document.
This calculation method can be used only if the evaluated sample fulfils the requirement for ester content as reported in EN 14214.
The precision statement of this test method was determined by calculation from a Round Robin exercise with iodine values in the range of 16 g iodine/100 g to 126 g iodine/100 g.
The test method is also applicable for higher iodine values; however, the precision statement is not established for iodine values above 126 g iodine/100 g.
NOTE 2 For the purposes of this document, the term “% (m/m)” is used to represent the mass fraction.