THE CHARACTERIZATION OF SHALE OIL BY HIGH RESOLUTION CHROMATOGRAPHIC TECHNIQUES

• Main Author: CROWLEY, RAYMOND JOSEPH
• Language: ENG
• Published: ScholarWorks@UMass Amherst 1981
• Subjects: Analytical chemistry|Energy
• Online Access: https://scholarworks.umass.edu/dissertations/AAI8110319

A class separation technique for shale oil based on normal phase partition high performance liquid chromatography was developed using a 20 (mu)m cyano bonded substrate. Separation within 30 minutes is achieved between aliphatic (alkane/alkene), aromatic and polar fractions. Reproducible resolution with less than 5% class overlap was achieved. Oil samples from TOSCO II, Paraho, and In Situ retorting processes were compared for aliphatic, aromatic and polar content. After preparative class separation characterization was carried out by fused silica and glass wall coated open tubular capillary gas chromatography and by analytical high pressure liquid chromatography. Compound identification of the aliphatic and aromatic fractions was performed by capillary gas chromatography/mass spectrometry. Mass spectra of the major components were obtained by electron impact at 70 eV. Mass scans were recorded between 50-350 AMU at a scan rate of 128.6 AMU/sec. Mass spectra were compared with those of standards and structural isomers were identified by comparison of their retention times with available standards. A Perkin-Elmer gas phase UV absorbance detector for gas chromatography was evaluated. Parameters such as detection limit, selectivity ratios, dynamic range and compatability with capillary columns were evaluated. Following this characterization the detector was employed for the analysis of shale oil aromatics. Oil shale bitumens, defined as the fraction of shale that is soluble in benzene, were prepared by exhaustive extraction of the raw shale with a 2/1 benzene/methanol mixture. The sample was then separated into paraffinic and aromatic fractions by preparative liquid chromatography on 32-63 (mu)m silica. Each fraction was then analyzed by both packed and high resolution glass capillary gas chromatography with compound identification by GC/MS. The development of coating techniques for high resolution glass capillary columns was also stuided. Both support coated open tubular (SCOT) and wall coated open tubular (WCOT) columns were prepared. The effects of various surface pretreatment techniques such as HCl etching, the use of surfactants, and the effect of different solvents on the overall column efficiency was performed. Both borosilicate (Pyrex) and soda lime glass were employed.