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Highly dispersed LaCo1−x−yCuxTiyO3/KIT-6 perovskites were synthesized by the citrate method with inert mesoporous KIT-6 addition. The KIT-6 matrix was removed by dissolution in 7% NaOH aqueous solution. The dispersity of perovskites probably varies depending on the largest cation and its content at the B position of the perovskite ABO3 structure. The CoS=23+/CoS=03+ ratio increases with the increase in copper content and in the presence of Ti4+. It may be explained by the compensation of the distortion of the perovskite structure. The maximum syngas conversion is achieved at nCo/nCu = 7/3. At a higher copper content, the activity of the samples decreases due to the formation of large copper particles (up to 40 nm) in the course of the reduction. The selectivity for alcohols increases with an increase in the proportion of copper and reaches maximum values at a ratio of nCo/nCu close to 1. The distribution of alcohols is the same for all samples, except for LaCo0.35Cu0.35Ti0.3O3/KIT-6. It can be assumed that the synthesis of alcohols proceeds on bimetallic CoCu particles 3 nm in size and cobalt particles 4–6 nm in size, most likely enriched with copper on the surface. [ABSTRACT FROM AUTHOR]

Perovskite-type samples La 1-x Ca x Co 1-x Ti x O 3 /KIT-6 (x = 0–0.5) were synthesized by citrate method. KIT-6 is partially embedded in the perovskite structure. The complete reduction of cobalt in perovskites in the presence of KIT-6 occurs at a temperature of ca. 670 °C due to the formation of a cobalt silicate phase. With the substitution of titanium for cobalt cations, the complete reduction of cobalt occurs at temperatures above 720 °C. The proportion of cobalt that is reduced at temperatures below 500 °C increases with an increase in the ratio of Co3+/Co2+ cations. Partial substitution of cobalt cations with titanium cations decreases the selectivity ratios S CH3OH /S C2+OH and S CH4 /S C2-8. The introduction of calcium cations leads, proportionally to its content, to a strong decrease in selectivity to methanol and an increase in selectivity for light hydrocarbons C 2-8 in syngas conversion. It was shown that the maximum selectivity for higher alcohols with a low selectivity for methanol is observed at x = 0.3 on a sample containing calcium. A significant amount of the cobalt carbide phase Co 2 C in the used KIT-6-free sample of LaCoO 3 is accompanied by the predominance of the methanation reaction (CH 4 selectivity 58.7%). The synthesized samples on KIT-6 have higher selectivity to alcohols compared to a conventional CoAl oxide catalyst and somewhat lower activity in syngas conversion. [Display omitted] • High surface area perovskite La 1-x Ca x Co 1-x Ti x O 3 /KIT-6 catalysts were synthesized. • Distribution of LaCoO 3 /KIT-6 products is similar to CoAl catalyst. • At Ca/Co = 0.15–0.43 and Ti/Co = 0.43 selectivity for higher alcohols doubles. • Calcium introduction decreases S CH3OH proportionally, wherein S C2-8 increases. • An increase in size of Co particles leads to formation of Co 2 C and an increase in selectivity for CH 4. [ABSTRACT FROM AUTHOR]