1.1 This International Standard specifies a method for determining the content of olefinic and aromatic hydrocarbons in gasolines, naphthas, kerosenes and other petroleum dis illates, containing little or no butanes or butenes and having a dis illation point of 90%. , determined according to the method specified in is 3405, is not higher than 315 °C. The method is not directly applicable to the determinations of olefinic and aromatic hydrocarbon contents greater than 98.5% (VIV) if a 10 ml test portion is used, nor to the determinations of contents greater than 97% (VIV) if a 5 ml test portion is used. NOTE — For best results, depentanized test portions should be used. 1.2 The results obtained according to the specified procedure include all acid-absorbable products contained in the test portion. These products include, in addition to olefinic and aromatic hydrocarbons, variable proportions of compounds containing sulfur, nitrogen, oxygen or combinations thereof. This is why, when interpreting the results, it is necessary to take into account the presence or absence of appreciable quantities of products other than hydrocarbons. In petroleum dis illates, the proportion of these products is generally low enough for the result to be considered as corresponding to a measurement of total olefinic and aromatic hydrocarbons and, in the absence of olefins (bromine number less than 1), as corresponding to a measurement of aromatics when it has undergone an empirical correction to take into account the retention of saturated hydrocarbons in the reagent. This solubility correction varies depending on the product analyzed. Furthermore, the measurements can be influenced by certain secondary phenomena such as the variation in volume which occurs when different hydrocarbons are mixed; these phenomena have, in general, effects significantly lower than the precis on of the method and are therefore negligible.
NBN T 52-022-1978 history
1978NBN T 52-022-1978 Petroleum distillates - Determination of olefinic plus aromatic hydrocarbons content