## 1 Introduction  
The role of the hydrogenation processes has increased in modern oil refining. The main interest in the conversion of sulfur compounds is largely determined not so much by the problems of oil refining, coal chemistry, and synthetic liquid fuel, but by the rapid development of hydrotreating processes of petroleum fuel from sulfur compounds. The need to develop these processes, in turn, was due to the fact that it was necessary to prevent the release of sulfur oxides when burning fuels in engines and boiler plants, as well as the fact that the presence of sulfur compounds in motor fuels accelerates corrosion and wear of engines and reduces their power. In addition, sulfurous compounds accelerate precipitation during the storage of petroleum fuels, which depends on the amount of sulfur bonding with aliphatic carbon [1; 2; 3; 4].  
Increasing the demand for motor fuels, tightening the requirements imposed on them, and involving raw materials of various compositions in the reprocessing procedure require new approaches to the synthesis of new catalysts. In the hydrogenation process of the heavy hydrocarbon feedstock, a critical role is played by the catalyst support, since it serves a significant purpose in the activity and stability of the catalyst, and therefore the selection of a suitable, inexpensive, and readily available supporter is crucial for the active catalyst preparation. Catalytic activity can be regulated by controlling the particle size, composition, shape, and nature of metal interaction with the supports such as Al\({}_{2}\)O\({}_{3}\), MgO, TiO\({}_{2}\), zeolite, silica, carbon, and mesoporous materials [5]. With the development of material science, clay mineral materials, which play a significant role in scientific research, have gained universal recognition, thanks to which they could possibly be used as cheap substitutes for expensive carbon nanotubes (CNT) or other nanomaterials [6; 7]. Chrysotile is one of most widely used nanostructured silicates and can be easily found in nature. The use of chrysotile asbestos as a carrier for the hydrogenation of heavy oil residues, oil sludge, and coal tar to produce motor fuel is of important theoretical and practical significance. The chrysotile nanotubes have a purely surface structure, which allows them to be considered as the most suitable object for physical sorption. Literature analysis has shown that chrysotile is not used as a support for heterogeneous catalysts in the hydrogenation of polycyclic aromatic hydrocarbons. However, ref. [8] showed the hydrogenation of 4-nitropenol in the presence of a AgNPs/SiO\({}_{2}\)NWs nanocatalyst, where leached chrysotile acts as a support. Thanks to the developed surface and oriented packaging of nanotubes with hydrophilic properties, the chrysotile has a high sorption ability [9; 10; 11].  
In oil refining, special focus is given to the conversion of organosulfur compounds, which are part of heavy hydrocarbon raw materials, which reduce the quality of obtained motor fuels [12]. The oil stock contains the organosulfur compounds of various reactivities in catalytic processes. Hydrogenation and hydrogenolysis constitute one of the primary directions of the conversion of organosulfur compounds in the hydrocatalytic process [13; 14].  
In this study, experiments were performed on the hydrogenation of an individual compound--benzothique, which allows the simulation of the direction and nature of transformations in hydrocatalytic processes (hydrotreating, hydrocracking) of components of heavy oil fractions and the assessment of the activity and selectivity of chrysotile-based catalysts with supported active metals (Ni, Co).  
The purpose of the work was to establish optimal conditions for nanocatalyst preparation based on chrysotile with supported metals (Ni, Co) for the hydrogenation of benzothiophene.