New approaches to study of the liquefaction sapropel products obtained by carrying out the process in supercritical ethanol

• Main Authors: Krivonos, O. I., Kopytov, M. A., Belskaya, O. B.
• Format: Conference Proceeding
• Language: English
• Subjects: Aluminum oxide; Aromatic compounds; Atomic properties; Catalysts; Composition; Esters; Ethanol; Gas chromatography; Hydrogen; Infrared spectroscopy; Liquefaction; Low molecular weights; Mass spectrometry; NMR spectroscopy; Oxygen atoms; Sulfur content
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0026711

The liquefaction of sapropel in the East Siberian region using ethanol under supercritical conditions (260 °C, 18 MPa) was studied. The influence of the hydrogen atmosphere and the CoMo/Al2O3 catalyst on the yield and composition of liquid products was established. The presence of a reactive hydrogen atmosphere and a catalyst increased the conversion of organic mass of sapropel (α) from 41.1 to 75.9 wt.%. Gas chromatographic–mass spectrometry, FT-IR, and NMR spectroscopy methods have shown that the bulk of liquid liquefaction products are esters (30.1−46.6 rel.%), alkyl derivatives of phenol (9.5−21.6 rel.%), and nitrogen-containing compounds (12.9−18.9 rel.%). The addition of hydrogen and a catalyst reduces the content of heteroatomic compounds in liquid products and increases the hydrogen content from 7.26 to 8.86 wt.%. The component composition of liquid products of liquefaction in supercritical ethanol was studied. It was shown that the introduction of a catalyst and hydrogen increases the yield of oils in the maltene fraction by 1.5 times. Structural-group analysis of liquid products showed that the average molecule is characterized by a low molecular weight MW = 200 amu. and contains 11 carbon atoms. The average molecule contains 1 aromatic ring with alkyl substituents and 2 oxygen atoms. The sulfur content is low, about 3 atoms per 100 average molecules.