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CO2 is a harmful greenhouse gas, a product of chemical emissions, the combustion of fossil fuels and car exhausts, and it is a widely available source of carbon. The review considers various ways of hydrogenation of carbon dioxide into components of motor fuels - methanol, dimethyl ether, ethanol, hydrocarbons - in the presence of heterogeneous catalysts. At each route of conversion of CO2 (into oxygenates or hydrocarbons) the first stage is the formation of CO by the reverse water gas shift (rWGS) reaction, which must be taken into account when catalysts of process are choosing. The influence of chemical nature, specific surface area, particle size and interaction between catalyst components, as well as the method of its production on the CO2 conversion processes is analyzed. It is noted that the main active components of CO2 conversion into methanol are copper atoms and ions which interact with the oxide components of the catalyst. There is a positive effect of other metals oxides additives with strong basic centers on the surface on the activity of the traditional copper-zinc-aluminum oxide catalyst for the synthesis of methanol from the synthesis gas. The most active catalysts for the synthesis of DME from CO2 and H2 are bifunctional. These catalysts contain both a methanol synthesis catalyst and a dehydrating component, such as mesoporous zeolites with acid centers of weak and medium strength, evenly distributed on the surface. The synthesis of gasoline hydrocarbons (≥ C5) is carried out through the formation of CO or CH3OH and DME as intermediates on multifunctional catalysts, which also contain zeolites. Hydrogenation of CO2 into ethanol can be considered as an alternative to the synthesis of ethanol through the hydration of ethylene. High activation energy of carbon dioxide, harsh synthesis conditions as well as high selectivity for hydrocarbons, in particular methane remains the main problems. Further increase of selectivity and efficiency of carbon dioxide hydrogenation processes involves the use of nanocatalysts taking into account the mechanism of CO2 conversion reactions, development of methods for removing excess water as a by-product from the reaction zone and increasing catalyst stability over time.

The main challenge today is to find new alternative energy sources. Reduction of oil, gas and coal production can be achieved through the rational use of biomass as a raw material for fuels and lubri-cants. Thermochemical treatment of biomass allows to obtain raw materials for a number of process-es, in particular the separation of hydrocarbon components and their catalytic treatment allows to ob-tain alternative components for motor fuels. The main advantage of using hydrocarbon fractions from biomass is that they are completely free of sulfur- or nitrogen-containing compounds that play the role of catalytic poisons. Catalytic studies were performed in a flow reactor at a charged catalyst volume of 30 cm3, a reac-tion zone temperature of 350 ± 5 °C and a pressure of 0.1 MPa. The feedstock was fed to the reaction zone using a pump at a constant rate of 1 h-1. The direction of supply of raw materials from top to bot-tom. In this work it is shown that industrial aluminosilicates are structural compounds (Cat.25, Cat.38, Cat.50, Cat.80) and show catalytic properties in the cracking process, which is reflected in the increase of octane number from 8 to 20 units. The higher their cracking activity, the more gaseous products are formed and the fractional composition changes in the direction of isomeric hydrocarbons, which is confirmed by gas chromatographic analysis. According to the amount of gas phase and the composi-tion of liquid products, it should be noted that the most active catalyst was the sample Cat.25. This effi-ciency is related to the chemical composition and methods of synthesis of the presented catalysts. The latter by their nature contain cations of aluminum (Al3+) and silicon (Si4+), which certainly affects the formation of Bronsted acid centers, which are responsible for the cracking process. In turn, catalysts of the type Cat.1 and Cat.2 with a significant content of aluminum and no catalytic effect can be charac-terized as a mechanical mixture of these basic oxides, and not an aluminosilicate matrix with a certain structure. Based on the obtained results, renewable biomass is a potential source for obtaining hydrocarbon fractions, which after catalytic treatment processes can serve as high-quality high-octane components of alternative fuels.

The catalytic process for methanol production by synthesis gas conversion under the conditions of mechanochemical activation (MCA) of copper-zinc-aluminum oxide catalyst in the temperature range 160–280 °C at a pressure of 0.1 MPa are investigated. The use of mechanical action force is one of the promising ways to improve the activity of heterogeneous catalysts designed to simplify the manufacturing process lines, improving the efficiency of catalytic processes and reduce the cost of the target product. Given the importance of technology for methanol production on copper-zinc-aluminum oxide catalysts and high demand for methanol in the world [1–3], clarification of the peculiarities of the process of methanol production by synthesis gas conversion in terms of mechanical load on the catalyst is important in scientific and applied ways. It is established that specific catalytic activity, performance of methanol synthesis catalyst and the conversion of initial reagents are increased in the conditions of mechanochemical activation, because of the increasing concentration of defects and formation of additional active centers. It is revealed that mechanochemical treatment of copper-zinc-aluminum oxide catalyst can reduce reaction initiation temperature and optimum temperature synthesis by 20–30 °C, and increase the maximum performance of the catalytic system. Increase of the catalyst activity under mechanical stress is explored by increase of defect concentration of crystal lattice of the catalyst, as confirmed by the tests of catalyst surface structure by scanning electron microscopy, Raman spectroscopy and X-ray analysis. A new effective method for synthesis gas conversion into the methanol under conditions of mechanochemical activation of the catalyst can be used in industry as an alternative to methanol production at high pressures.