Shale oils components

Also important is the use of the modem chromatographic methods to separate and identify individual components in commercial cmde shale oil. The use of efficient gas chromatographic columns coupled with ancillary techniques such as mass spectrometry and vapor-phase IR spectroscopy allows the identification of individual shale oil components. A principal part of this study is the comparison of diflFerent types of open tubular columns for the separation of the alkane-alkene fraction of shale oil WCOT, SCOT, and PLOT columns are examined. Gas chromatographic separation of shale oil acids and bases also is performed allowing the identification of these components. The potential utility of subtractive pre-columns in HPLC analysis is illustrated also. 

Pyrolysis studies of oil shale, gas phase subtractive investigations of evolved volatiles, and open tubular gas chromatography— vapor-phase IR spectroscopy of shale oil components were carried out in the interfaced vapor-phase thermal analysis laboratory which has been described in detail elsewhere (4,5). A general block diagram of this system is shown in Figure 1. 

High-Pressure Liquid Chromatography. There appears to be little doubt that HPLC will play a prominent part in future separation of shale oil components. Liquid-phase methods have long been important in work-up procedures for analysis and their extension to high resolution areas is under extensive study. One particular example is chosen to illustrate the capabilities of HPLC that of its combination with reactive pre-columns for quantitative estimation of oil compound types. 

Wame, M.S., Connell, D.W., Hawker, D.W. and Schiiurmann, G. (1989a). Prediction of the Toxicity of Mixtures of Shale Oil Components. Ecotox.Environ.Safe., 18,121-128. 

R. R. Pelroy and M. R. Petersen, Mutagenicity of Shale Oil Components, Presented at the Symposium on Application of Short-Term Bioassays in the Fractionation and Analysis of Complex Environmental Mixtures, Williamsburg, Virginia, February 21-23, 1978, pp. 461-475, EPA.600/9-78-027, September 1978. 

Man has served as the unintentional guinea pig for the identification of some major classes of carcinogens. These include the polycyclic aromatic hydrocarbons (PAH), or polyarenes, which have been identified as the active components of soot, which was recognized by the London surgeon Percivall Pott two centuries ago as responsible for cancer of the scrotum in chimney sweeps. Subsequently, polycyclic hydrocarbons have been implicated as agents responsible for skin cancer in other occupations such as shale oil distillation and mule spinning in the cotton industry. 

Commercializing the vast oil shale resources could greatly add to the country s energy resources. Shale oil could have an effect similar to the 175 billion barrels of oil from Alberta tar sands to Canada s oil reserves. As a result of the commercial effort, oil from tar sand production now exceeds one million barrels per day. Oil shale in the United States is as rich as tar sand and could become a vital component in America s future energy security. 

Asphaltene is an essential component of any dark-colored, heavy, viscous and nonvolatile oil, regardless of the oil source. Asphaltene can be obtained from the oil extracted from a naturally occurring organic-rich fossil material by a simple solvent fractionation. Asphaltene also can be obtained from the chemical conversion product of a solid fuel, such as pyrolysis or catalytic hydrogenation of coal or shale. The former is an example of the asphaltene isolated from native petroleum oil. An example of the latter is the asphaltene obtained from a synthetic crude, such as shale oil or coal liquid. 

Many questions concerning the nature of petroleum asphaltenes remain unresolved (1) What is the chemical composition of petroleum asphaltenes (2) What are the molecular weights of asphaltene components (3) Why are asphaltenes precipitated from solution in petroleum by the addition of a hydrocarbon solvent such as n-pentane In this chapter we attempt to answer these questions. In addition, we suggest that asphaltene formation is a general phenomenon that is pertinent to the chemistry of coals, tar sand bitumens, shale oil, and other complex solutions of organic compounds. 

Materials for selective vapor-phase trapping have been considered by various workers (6,7). Traps used in the present study included molecular sieve 5A for subtraction of straight chain hydrocarbons, sodium bisulfate and phosphoric acid for subtraction of shale oil bases, and alumina for subtraction of acidic components. 

A chromatogram of crude shale oil with no separative work-up on the 35-ft OV-101 PLOT column is shown in Figure 3. Comparison with the PLOT chromatogram in Figure 2 shows that the resolution of the alkane-alkene pairs is virtually unaffected by the presence of the other oil components. 

Despite the usual preference in GC for the application of more polar stationary phases for the resolution of polar species, the former may be applied usefully for nonpolar separations. Figure 4 illustrates the resolution of the alkane-alkene pairs of the hydrocarbon fraction of shale oil (sample as in Figure 2), on a FFAP PLOT column (100ft). FFAP is Carbowax 20M terminated with terephthalic acid residues. This column selectively retains olefins and enables base-line resolution of the alkane-alkene pairs. The only disadvantage of this phase is its temperature limitation of ca. 250°C. Identification of the numbered peaks in Figure 4 was achieved by interfaced MS (components are listed in Table 1). 

On considering the optimal chromatographic conditions for analysis of the more polar constituents of shale oil it becomes apparent that both packed columns and PLOT columns have useful features. An example involves the acid-component fraction of shale oil obtained by sodium hydroxide extraction, removal of nonpolar species with benzene, methyl-... 

These chromatographic examples demonstrate the utility of PLOT columns for the resolution of the various chemical constituent fractions of shale oil and their compatibility with interfaced IR and mass spectral peak identification. The major advantage of the higher column peak capacity of the PLOT columns makes the latter measurements more feasible particularly for the minor components in the chromatogram. 

Figure 13, HPLC of total shale oil. Cation exchange precolumn subtraction of shale oil bases. Conditions to retain the most basic components only. Column, 4 mm X 25 cm Partisil 10, Mobile phase, 60/30/10, C HiJ CH2CI2/THF, Flow rate, 50 mL/min, Pre-column 1/8 in, X 4 in, Dowex 50W X 8 Resin pre-activated.

Figure 13 shows a total shale oil liquid chromatogram in the absence and in the presence of a cation exchange pre-column. The subtracted basic components are quantitated from the difference in areas with and without the pre-column. The subtracted basic species were determined as ca. 12.9% of the total crude shale oil using this method. 

The principal components of the coal liquids were the neutral compounds and the aromatic compounds including PNA. See Figure 6— light oil, wash solvent, and recycle solvent.) For the shale oil we analyzed, aliphatic hydrocarbons were most abundant. Lesser amounts of alicyclic... 

In these studies, the same fossil-derived crudes were used as described in the alkane fractionation work, i.e., two coal liquids, a shale oil, a petroleum, and a petroleum blend. Estimates of PAH components showed the highest overall amounts in shale oil and in one of the coal liquids. The petroleums contain the least amount and are comparable with the other coal liquid in this respect. Also, the petroleums have little detectable material of more than three rings, while the coal liquids contain appreciable quantities of five-six-ring PAH. Shale oil PAH compounds are predominantly in the 2-3-ring class with a high degree of alkyl substitution. 

Dimethylthietane is a component of the secretion from the anal gland of the mink (Mustek vision). the European polecat (M. putorius) and ferret. The ferret also produces cis- and trans-2,3-dimethylthietane, 2-n-propylthietane, and 2-n-pentylthietane. 2-n-propylthietane is the major malodorous substance secreted by the anal gland of the male stoat (M. erminea). The female stoat secretes 2-ethylthietane. Thietane, itself, is said to be a component of shale oil. ... 

Removal of Nitrogen-Containing Components from Shale Oil and Related Fossil Fuels... 

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