The composition of kukersite shale oil

Abstract

Pyrolysis oils are usually considered as substitutes for crude oil; however, they can also be sources of valuable compounds. One such pyrolysis oil is shale oil obtained by pyrolysis of kukersite oil shale. Kukersite shale oil consists mainly of aromatic rings with straight alkyl side chains. For samples with comparable boiling point distributions, kukersite shale oil has a higher proportion of aromatic rings than petroleum and many other shale oils. Sulfur, nitrogen, and oxygen are often incorporated into the ring structures, with much of the oxygen also present as phenolic hydroxyl groups. To evaluate the potential for producing some specific compounds from kukersite shale oil foundational data on the composition is needed. In this article, new experimental data on the elemental composition and infrared spectrum of kukersite shale oil is analyzed to investigate its composition. To get detailed information on how the composition of the oil changes depending on the average molecular weight of the oil fraction, the shale oil was separated into narrow boiling fractions using distillation. This gives more detailed data on different portions of the oil than earlier datasets. Additionally, this data is for oil produced from newer solid heat carrier retorts. The results show that the nitrogen content in kukersite shale oil increases with the boiling temperature, with the heaviest fractions containing about 0.3 wt%. Sulfur content reaches a maximum of almost 2 wt% for fractions boiling between 150 and 190 °C, and heavier fractions contain about 0.7 wt%. Similarly, the proportion of hydroxyl groups in kukersite shale oil peaks in the fraction boiling at about 320 °C, with heavier fractions containing more aromatic and alkyl functional groups. The elemental composition of kukersite shale oil is also compared to that of other shale oils.

Keywords

• kukersite
• shale oil
• sulfur
• nitrogen
• ftir spectroscopy
• functional groups.