Catalytic hydrogenation and heteroatom removal for isopropanol soluble organic matter of Dongming lignite

Abstract Soluble organic matter in Dongming lignite was obtained via thermal dissolution using isopropanol as the solvent and named as DLIP. Catalytic conversion of DLIP was carried out using Co-Mo/γ-Al2O3 as the catalyst to reach hydrogenation, hydrocracking and heteroatom removal. DLIP and the corresponding catalytic products were analyzed by Fourier transform-infrared spectroscopy (FT-IR), gas chromatography/mass spectrometry (GC/MS) and Orbitrap mass spectrometry (Orbitrap MS). According to the FT-IR data, the contents of alcohols and phenols increased with reaction temperature due to the cleavage of C O bonds in macromolecules of coal. The soluble organic matter and its catalytic hydrogenation products analyzed by GC/MS were classified into 10 classes, and Orbitrap MS was used to obtain the componential distribution of heteroatom containing compounds. Moreover, weighted-mean double bond equivalent (DBE) value and weighted-mean carbon number (CN) were calculated. The decrease of weighted-mean DBE/CN after catalytic conversion demonstrated ring opening reactions and cleavage of bridge-bonds.