Effect of final pyrolysis temperature on the composition and structure of shale oil: Synergistic use of multiple analysis and testing methods

As the focus of research on the pyrolysis mechanism of oil shale shifting towards the molecular level, identifying the effect of pyrolysis temperature on the molecular composition and structure becomes all the more important. In this study, the molecular characteristics of shale oils produced at different final pyrolysis temperatures was compared and analyzed through synergistic use of multiple analysis and testing methods. The results showed that compared with the traditional gas chromatography-mass spectrometry (GC-MS), comprehensive two-dimensional gas chromatography-time of flight mass spectrometry (GC x GC-TOF/MS) has obvious advantages in the characterization of heteroatoms and cycloalkanes. Fourier transform infrared spectrometry (FT-IR) can supplement the deficiency of nuclear magnetic resonance (NMR) in the characterization of oxygen-containing functional groups. With the increase in final temperature, the aromatization reaction of cycloalkanes intensified. Conversely, the degree of alkane branching and carbon chain length decreased. Based upon mutual verification and supplement of various analysis results, a novel method was proposed for the comprehensive molecular characterization of complex liquid fuel oil. According to the advantages and characteristics of different detection methods, synergistic use of multiple methods for different fractions is an important research direction for the molecular characterization of complex liquid fuel oil in the future. (c) 2022 Published by Elsevier Ltd.

Automated summary

As research on the pyrolysis mechanism of oil shale focuses on the molecular level, the effect of pyrolysis temperature on molecular composition and structure becomes increasingly important. This study compared and analyzed the molecular characteristics of shale oils produced at different final pyrolysis temperatures using multiple analysis and testing methods. The results showed that different detection methods have their advantages in characterizing the molecular properties of pyrolysis oils, and synergistic use of multiple methods is an important research direction for the molecular characterization of complex liquid fuel oil in the future.