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Efficient catalytic technologies for converting CO 2 with hydrogen into value-added chemicals and fuels can help to solve the environmental problems related with large CO 2 emissions. Among of the most interesting products that can be synthesized from CO 2 are synthetic natural gas, methanol and DME, methane and higher hydrocarbons, higher alcohols. In this mini review, we highlight the recent advances in the development of heterogeneous catalysts and processes for of CO 2 hydrogenation to these products. Recent research to develop highly active and selective catalysts based on controlled synthesis – active phases, promoters, supports, thermodynamics, are presented. [Display omitted] • Hydrogen is efficient reagent for CO 2 transformation into valuable products. • Heterogeneous catalytic hydrogenation is an attractive method of CO 2 processing with hydrogen. • Catalysts for CO 2 hydrogenation are to be active, selective, stable, reusable for high efficiency of the process. [ABSTRACT FROM AUTHOR]

Mixed copper-containing spinel-type compounds CuCr 1 Fe 1 O 4 , CuCr 1 Al 1 O 4 and CuFe 1 Al 1 O 4 were studied by means of XRD and HREM after calcination at 650 °C in the air and treatments in a hydrogen-containing medium at 270–210 °C (H 2 :He = 5:95; H 2 :CO:H 2 O = 50:7:43). The effect of the chemical nature of Mе 3+ cation on the structural-morphological characteristics of oxide systems and their transformations in a reducing medium was investigated. It was shown that the nature of Me 3+ cation makes it possible to control the structural characteristics, particularly in the reduced state. [ABSTRACT FROM AUTHOR]

The paper presents the low-temperature nitrogen adsorption, TG, XRD, IR spectroscopy, XPS, TEM and SEM data for ruthenium promoted (0.2–1 wt.%) Сo-δAl 2 O 3 catalysts and characteristics of the catalysts in Fischer-Tropsch synthesis after their activation under the conditions ensuring the reduction of comparable fractions of metallic cobalt. It was shown that cobalt in oxide precursors is a component of the spinel-like Со 3-x Al x O 4 phase containing the impurity anions СО 3 2− , NO 3 − , ОН − , and NO in promoted samples, which belong to the thermolysis product of the Ru precursor. Average sizes of Со 3-x Al x O 4 crystallites are in a range of 5–10 nm. As ruthenium content in the catalyst increases upon reduction, the temperature of metallic phase formation decreases substantially (by more than 150 °C). After the reduction, selectivity of promoted catalysts for α-olefins and high-molecular hydrocarbons was higher in comparison with unpromoted catalysts, without a noticeable decrease in catalytic activity. Therewith, in 0.5–1.0 wt.% catalysts, a part of ruthenium forms individual ultradispersed metallic particles ca. 1 nm in size that are located on the surface of oxide support and are not active in Fischer-Tropsch synthesis. The oxide layer decorating the surface of metallic cobalt particles is also strongly enriched with ruthenium. In the 0.2 wt.% catalyst, the major part of ruthenium resides in metallic cobalt particles. Although the ruthenium-cobalt alloy segregates with enrichment of the surface with cobalt, the presence of ruthenium in the metallic particles and probably in the decorating oxide layer exerts a considerable effect on selectivity of the catalysts. [ABSTRACT FROM AUTHOR]