This review provides an analysis of recent scientific and engineering literature on chemical methods for CO₂ processing using heterogeneous catalysts. The following major uses of carbon dioxide are discussed: exhaustive hydrogenation; synthesis of hydrocarbons including light olefins; synthesis of oxygenates; and production of cyclic carbonates. Furthermore, the paper highlights the main design approaches for CO₂ conversion catalysts and formulates priorities for decarbonization using heterogeneous catalytic reactions.

Currently, the processes of obtaining synthetic liquid hydrocarbons and oxygenates are very relevant. Fischer-Tropsch synthesis (FTS) is the most important step in these processes. The products of thermal destruction in argon of the mixture [Co(NH₃)₆][Fe(CN)₆] and Al(OH)₃ were used as catalysts for CO hydrogenation. The resulting compositions were studied using powder X-ray diffraction, IR spectroscopy, elemental analysis, SEM micrographs. The specific surface area, pore and particle size distributions were determined. It was determined that the DCS-based catalysts were active in the high-temperature Fischer-Tropsch synthesis. The effect of aluminum in the catalyst composition on the distribution of reaction products was revealed.

Methods for the formation of stable iron-containing suspensions that exhibit activity in the conversion of synthesis gas to C5+ hydrocarbons by the Fischer-Tropsch method are proposed. By XRD and DLS methods it was determined that the formation of the Fe2O3 phase with a bimodal particle size distribution of 50 and 295 inn results in the formation of a suspension by the drop thermolysis method - the gradual introduction of the active metal precursor solution into the dispersion medium (mixture of hydrocarbons C19H40-C32H66). Pulsed introduction of the active metal precursor solution (flash-pyrolysis) into the reactor zone leads to the formation of the Fe3O4 phase with a particle size of 91 and 460 nm. By TEM and AFM methods it was established that, regardless of the slurry forming method, large active phase particles are agglomerates of a finer fraction of particles with an average size of 42 nm. The obtained suspensions demonstrated high activity in the Fischer-Tropsch synthesis under the slurry-reactor conditions, however, the degree of CO conversion is slightly higher in the case of the catalytic suspension prepared by the drop thermolysis method. It is shown that the method of forming the suspension significantly affects the fractional composition of the resulting reaction products. In the presence of a suspension obtained by drop thermolysis, the yield of liquid hydrocarbons reaches 130 g/m(3), while a high content of C19+ hydrocarbons is observed. The system formed by the method of flash-pyrolysis makes it possible to obtain mainly the gasoline (C-5-C-10) and diesel (C-11-C-18) hydrocarbon fractions. It should be noted that the products of the reaction have a high content of unsaturated hydrocarbons, which reaches 55%. Thus, the composition of the final products of FTS can be controlled by the choice of the catalytic suspension prepared method.

Copper-containing catalytic slurries with different concentrations of active metal precursor solutions are synthesized by drop thermolysis in situ in the hydrocarbon medium of a slurry reactor. According to dynamic light scattering, the particle size of the catalytic slurry dispersion phase is 3–4.5 nm and it remains almost unchanged during the synthesis. Using FTIR spectroscopy it is shown that the structure of precursors of slurry active species depends on the concentration of solution, which may influence the phase composition of catalytically active fragments of the surface during the reduction and synthesis of alcohols. It is demonstrated that alcohols may be synthesized from CO and H₂ in the slurry reactor in the presence of the formed nanosized slurries. It is revealed that the composition of alcohol phase products differs significantly with target product selectivity being comparable: at a low concentration of precursor solution a marked amount of methanol is contained in the mixture (up to 66%), while an increase in the concentration of precursor solution causes a rise in the proportion of higher molecular weight alcohols to 88%.