Obtaining fuel products by combined hydrogenation of coal and shale

Abstract

Background: Coal and oil shale are one of the promising types of organic raw materials that can largely compensate and replace petroleum products and gas in the future. Unlike other types of solid fossil fuels oil shales contain significant amounts of hydrogen in organic matter. The possibility of obtaining liquid and gaseous hydrocarbons from a mixture of coal and oil shale similar in composition and properties to petroleum products and natural gas allows us to consider them as important strategic resources.
 Aim: This article is devoted to the study of the process of obtaining fuel products of co-hydrogenation of coal and shale.
 Materials and methods: Coal from the Taldykol deposit and slate from the Kiin deposit were taken as objects of research. The process of coal and shale liquefaction was carried out on a laboratory installation at a pressure of 5 MPa and a temperature of 425°C, a reaction time of 1 h. Gas chromatographic and elemental analyses were used.
 Results: The research results showed that the optimal amount of shale added to coal is 15.0%. The implementation of the co-hydrogenation process under these conditions has increased the yield of liquid products by 10%, namely fractions with a boiling point of up to 200°C from 14.9% to 15.3%, fractions with a boiling point of 200–370°C from 22.1% to 26.4%, fractions with a boiling point above 370°C from 34.6% to 38.8%. Solid residue with a boiling point above 370°C tested as an organic binder for road construction.
 Conclusion: The proposed process technology also makes it possible to obtain gasoline and diesel fractions, which after appropriate hydrotreating can be used as motor fuels. The addition of oil shale to coal allows the process to be carried out under optimal conditions with a high degree of conversion into liquid products without coke formation. The degree of transformation of the mixture of organic mass of shale and coal is much higher than just coal.