Shale basic compounds

Characterization of the typical full range liquids reveals oxygen concentrations of 1.9 wt % in the H-Coal liquid and 0.9 wt % in the TOSCO shale liquid. Processing problems are expected with nitrogen removal because greater than 70% of the nitrogen compounds are basic... 

Biomarker compounds are present in varying proportions in both the bitumen and kerogen of oil shale, the non-bitumen forms being chemically bound or physically trapped by the kerogen and mineral matrix (6,23). For biomarkers occurring mainly in the bitumen, such as phytane and steranes, the production mechanism during oil generation is basically distillation, and the amount... 

Another way to separate nitrogen compounds from hydrotreated shale oil products is by adsorption chromatography. Experiments have been conducted where basic and neutral alumina have been used to separate shale oil into specific nitrogen-type fractions. Both a pumped-flow and gravity-flow method were executed. However, it was determined that the pumped-flow procedure was better since it enabled more control over experimental parameters such as flow rate. This separation scheme could be very useful because it has been applied to shale oil products produced under different hydrotreating conditions... 

Basic Nitrogen Compounds, The Shale-I jet fuel contained 976 ppm nitrogen of which 860 ppm nitrogen was acid extractable. 

Extraction of the Shale-I jet fuel with HC1 is approximately 90% efficient for removal of nitrogen containing material. Remaining in the fuel are 116 ppm of non-basic nitrogen compounds. Presumably, these compounds will be comprised primarily of pyrrole, indole and carbazole types. Only traces of substituted pyrroles and indoles were observed by FIMS in the basic nitrogen fraction (Table II). Shale oil nitrogen compounds have been characterized previously (15) and since carbazoles and pyrroles could not be titrated it is not surprising that they are also not efficiently extracted by IN HC1. 

High Temperature (Thermal) Stability. The high temperature stability of the Shale-I jet fuels was measured using the JFTOT technique (8 ). The thermal oxidative stability of the received fuel (976 ppm N) was measured. The fuel was then acid extracted, the isolated basic nitrogen compounds added back into the extracted shale fuel in varying quantity, and the thermal oxidative stability redetermined. A petroleum derived JP-5 was also subjected to JFTOT... 

Figure 1. GC of Shale-I basic nitrogen compounds using a 100-m OV-101 WCOT glass capillary column and a nitrogen-specific detector. Organic bases were extracted from the jet fuel with 1N aqueous HCl. Known compounds elute at indicated times.

In previously reported stability work with shale oil derived jet fuels (16) it was shown that the JFTOT thermal stability improved as the total nitrogen content decreased. In Table III, it is observed that the thermal stability of the Shale-I fuel improves as the concentration of basic nitrogen compounds decreases. In previous work (16) the lower nitrogen contents of the shale oil jet fuels were achieved by more severe hydrotreatment. 

Shale Oil JP-5 extracted with HCl, washed, and the isolated basic nitrogen compounds reintroduced to the shale oil fuel. 

Unlike their benzene counterparts, thienopyridines do not occur widely in nature. The basic components of a shale oil of high sulfur content were found to contain certain methylthieno[2,3-6]- and -[3,2-6]-pyridines, but no other natural occurrence of the compounds has been reported. 

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