DETERMINATION OF HYDROCARBON TYPES IN NAPHTHAS, GASOLINES AND KEROSENES - A REVIEW AND COMPARATIVE-STUDY OF DIFFERENT ANALYTICAL PROCEDURES

Standardized and non-standardized methods were used to study hydrocarbon types, namely paraffins, olefins, naphthenes and aromatics (PONA) in petroleum fractions. They were determined using the ASTM method of fluorescent indicator adsorption (FIA) and gas chromatographic techniques including capillary and valve switching multiple packed columns. Refinery products with final boiling points up to 270 °C were analysed, and results were reported according to carbon number. The advantages and disadvantages of the methods investigated are presented in this paper. Generally, results of multicolumn gas chromatography (MC-g.c.) were closer to FIA compared with capillary column gas chromatography (CC-g.c.). Furthermore, MC-g.c. gives better results and requires less interpretation time than CC-g.c., While changing calibration tables for radically different samples in CC-g.c. is a time consuming and tedious job, the other two methods do not require such an elaborate step. However, CC-g.c. is suitable for laboratories dealing with basically similar types of samples, or samples having a small number of components. © 1990.