Experimental Investigation of the Characteristics and Transformation Mechanism of Jimsar Oil Shale and Derived Shale Oil

Abstract

An experimental investigation of the characteristics and transformation mechanism of Jimsar oil shale and derived shale oil was conducted using a solid-state nuclear magnetic resonance spectrometer (13C NMR), Fourier transform infrared spectroscopy (FT-IR), liquid 1H NMR, and gas chromatography-mass spectrometry (GC-MS) techniques. The carbon skeleton structure of Jimsar oil shale is mainly composed of aliphatic carbons (70.5%), mostly containing straight-chain methylene (CH2), and aromatic carbon (29.31%). Derived shale oil is primarily made of aliphatic compounds that are dominated by n-alkanes and alkenes (comprising more than 70%). The nature of the conversion of oil shale to shale oil is the decomposition of aliphatic groups dominated by methylene structures in organic matter. Additionally, as the heating rate is increased, the secondary cracking reactions in shale oil could increase the contents of short-chain alkanes and alkenes, which could then enhance the secondary polymerization reactions that increase the generation of cycloalkanes and aromatic compounds. Shale oil demonstrates a maximum yield value of 6.32%, the largest carbon, hydrogen, and nitrogen contents, and a minimum oxygen content at the pyrolysis heating rate of 5 °C/min.