Shale high-resolution separations

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. 

It is clear that in the future high-resolution liquid-phase methods will be used increasingly in shale oil analyses, both in the separation mode and also as illustrated here in the subtractive mode for group quantitation. 

Another study from the LERC laboratories illustrates the increasing inadequacy of this type of separation as the molecular weight of the oil is increased (7). On a high-resolution liquid chromatography (LC) column (10,000 theoretical plates) which gave a wide separation of n-hexadecane from n-hexadecene-1, a shale oil saturate-olefin concentrate from a light distillate (400°-600°F) showed only an inflection point for the saturate, hindered-olefin break. A sample of heavy gas oil (800°-1000°F) saturate-olefin concentrate did not show even that. We must conclude from these data that the silica gel separation probably separates only mono-unhindered olefins from the saturates and aromatics with any degree of effectiveness. 

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