Standards Development

Scope

his European Standard specifies a test method for the determination of Fatty Acid Methyl Ester (FAME) content in diesel fuel or domestic heating fuel by mid infrared spectrometry, which applies to FAME contents of the three measurement ranges as follows:

— range A: for FAME contents ranging from approx. 0,05 % (V/V) to approx. 3 % (V/V);

— range B: for FAME contents ranging from approx. 3 % (V/V) to approx. 20 % (V/V);

— range C: for FAME contents ranging from approx. 20 % (V/V) to approx. 50 % (V/V).

Principally, higher FAME contents can also be analysed if diluted; however, no precision data for results outside the specified range is available at present.

This test method was verified to be applicable to samples which contain FAME conforming to EN 14214. Reliable quantitative results are obtained only if the samples do not contain any significant amounts of other interfering components, especially esters and other carbonyl compounds which possess absorption bands in the spectral region used for quantification of FAME. If such interfering components are present, this test method is expected to produce higher values.

Purpose

Given that Cells (classical version which consists of holder and window material) or any other liquid transmission accessory (as alternative for the classical liquid cell) with windows consisting of KBr, or NaCl, or ZnSe, or KRS-5, or CaF2 or BaF2, with accurately known path length, meet the requirement of this test method (wavelength working range) and that ZnSe cell is not hygroscopic, it should be made possible to use cells with this type of material and more modern equipment.

And correction of anerror: the gravimetric dilution described in 7.5 is incorrect and has to be replaced by volumetric dilution. The proposal is to replace the text by the following wording:

„The samples are diluted by transferring an aliquot of the sample corresponding to the envisaged dilution into a volumetric flask. The flask is filled to the mark with FAME free middle distillate fuel.

” The warning that the accuracy of the measured results depends on the best match of molecular masses (proportional to chain length) between the FAME material used for calibration and the FAME material in the analyzed sample can be solved by implementation of a correction factor