This document specifies the gas chromatographic determination of saturated, olefinic and aromatic hydrocarbons in finished petrol according to EN 228. Additionally, the benzene content, oxygenate compounds and the total oxygenate content can be determined.
The method is applicable for finished petrol with total aromatic content up to 50 % (V/V), total olefin content from about 1,5 % (V/V) up to 30 % (V/V), oxygenate compounds up to 15 % (V/V), total oxygen content from about 1,5 % (m/m) to about 3 % (m/m) and benzene content less than 2 % (V/V).
NOTE 1 For the purposes of this European Standard, the terms “% (m/m)” and “% (V/V)” are used to represent respectively the mass fraction and the volume fraction.
NOTE 2 While developing this method the final boiling point was limited to 215 °C.
NOTE 3 For oxygenate compounds, precision data has only been established on samples containing ethyl-tert-butyl ether (ETBE), methyl-tert-butyl ether (MTBE), tert-amyl-methyl ether (TAME) and ethanol. Applicability of this test method has also been verified for the determination of methanol, n-propanol, i-propanol, i-butanol, tert-butanol, acetone, and di-isopropyl ether (DIPE). However, no precision data have been determined for these compounds. If any of these oxygenate compounds are present in the sample, their contents should be determined by use of the appropriate test methods given in EN 228.
NOTE 4 Although this test method may be used to determine higher olefin contents up to 50 % (V/V), the precision for olefins was only tested in the range from about 1,5 % (V/V) to about 30 % (V/V).
NOTE 5 Although specifically developed for the analysis of finished petrol that contains oxygenates, this test method may also be applied to other hydrocarbon streams having similar boiling ranges such as naphthas and reformates.