GAS CHROMATOGRAPHY-MASS SPECTROMETRY ANALYSIS OF CHROMATOGRAPHIC FRACTIONS OF NIGERIAN BITUMEN

Abstract

This research was carried out to separate bitumen sample obtained from Agbabu in Ondo state into two fractions by elution glass column chromatography using alumina and mixed silica-alumina as the stationary phase. The aliphatic and aromatic fractions with raw bitumen sample dissolved in n-hexane were analyzed using Gas Chromatography-Mass Spectrometry. The results show that the nature of the stationary phase has an impact on the colors of the fractions obtained. The aliphatic fraction eluted with alumina stationary phase contains 25 compounds with a total composition of 86.5% and the most significant compound was Cyclotrisiloxane, hexamethyl- with a composition of 13.9%. The aromatic fraction eluted with alumina stationary contains 24 compounds with a total composition of 99.1% and the most significant compound was 1,3-Bis(trimethysily)benzene with a composition of 13.4%. The aliphatic fraction eluted with mixed silica-alumina stationary phase contains 21 compounds with a total composition of 98.3% and the most significant compound was (Z)-9-Octadecenoic acid with a composition of 26.1%. The aromatic fraction eluted with mixed silica-alumina stationary phase contains 16 compounds with a total composition of 99.2% and the most significant compound was benzo[h]quinoline,2,4-dimethyl- with a composition of 10%.The bitumen sample dissolved in n-hexane contains 45 compounds with a total composition of 98.4% and the most significant compound was (Z)-9-Octadecenoic acid with a composition of 27.5%.