Gasoline aromatic hydrocarbon content detection

Aromatic hydrocarbons mainly include monocyclic and polycyclic aromatic hydrocarbons, aromatic olefins, certain dienes, as well as compounds containing sulfur and nitrogen, or oxygen-containing compounds with higher boiling points. Aromatic hydrocarbons are a gasoline blending component with high octane and calorific values, but their combustion can lead to the formation of carcinogenic benzene and increase the risk of combustion in automobilesNO_x、 HC and COEmissions. In addition, the increase in aromatic hydrocarbon content increases the tendency for carbon deposition in the combustion chamber, which raises the engine's requirements for gasoline octane rating. The control of aromatic hydrocarbon content in gasoline in our country not only aims to reduce harmful emissions, but also considers maintaining the necessary level of octane rating.GB 17930-2016Regulations on Automotive Gasoline, including Automotive Gasoline (IV, V)aromatic content(Volume fraction) not greater than40%.

The determination of the volume fraction of aromatic hydrocarbons in petroleum fractions is crucial for characterizing the quality characteristics of components such as gasoline blends. The detection of aromatic hydrocarbon content in gasoline can be based onGB/T11132The fluorescence indicator adsorption method is used for measurement, and the summary of the test method is: take about0.75mLThe sample is injected into a glass adsorption column containing activated silica gel, and a thin layer of silica gel containing a fluorescent dye mixture is installed in the separation section of the adsorption column. After all the samples are adsorbed on the silica gel, add alcohol to desorb the samples and apply pressure to make the samples flow down the column. The various hydrocarbons in the sample are separated into aromatic hydrocarbons, olefins, and saturated hydrocarbons based on their adsorption capacity. Fluorescent dyes are also selectively separated from hydrocarbons, making the interfaces of various hydrocarbon regions clearly visible under ultraviolet light. Calculate the volume percentage of each hydrocarbon based on the length of each hydrocarbon band region in the adsorption column.