Determination of Fractional Distribution of Crude Oil by Gas Chromatography with Simulated Distillation

Gas chromatographic simulated distillation was applied to the determination of fractional distribution of crude oil.Heavy fraction of crude oil was analyzed by the high temperature simulated distillation (SIMD),and the light fraction by the technique of DHA hydrocarbon pre-preparation.Fractional distribution of crude oil was obtained through componental arrangement.Mixture of strainght chain alkanes (or n-alkanes) with C5-C120 was used as standard for correction of boiling point in the range of distillation from initial boiling point (IBP) to 750 ℃.Good repeatability was obtained by this method,giving values of standard deviation,at both the IBP and the final boiling point,less than 1 ℃,and values of RSD′s of various fraction yields less than 0.35%.Results obtained by this method were in consistency with those found by the method of true boiling point distillation.Yield differences between fractions under 500 ℃ were less than 2.5%.It was shown that the fractional distribution between 500-750 ℃ was valuable for further processing and utilization of the heavy fractions of crude oil.