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A higher selectivity to C2−C4 hydrocarbons and clean fuels without significant deactivation during CO hydrogenation by a typical Fischer‐Tropsch synthesis (FTS) was observed on the ordered mesoporous 5wt %Al‐modified Co3O4‐Fe2O3 bimetal oxides (m‐CoFe) at a Co/Fe molar ratio of ∼1, which was prepared by a hard templating and co‐infiltration method. The active sites were related with the partially oxidized Co nanoparticles as well as iron carbides. The structurally stable and strongly interacted ordered Co3O4‐Fe2O3 mesoporous structures were preferentially transformed to more brittle iron carbides with a simultaneous reduction of Co3O4 to metallic Co under a reductive FTS reaction condition. The m‐CoFe(1) itself without using any solid acid component revealed a higher C2−C4 selectivity of 21.1 % and C5+ selectivity of 67.9 % at CO conversion of 88.5 % with the corresponding rate of 2.77 mmol/(gcat⋅s) by enhancing its structural stability due to the partial formations of thermally stable spinel‐type CoFe2O4. The enhanced structural stability of the m‐CoFe(1) was attributed to the preferential formations of the strongly interacted and partially oxidized Co nanoparticles with the formation of active iron carbides as well. [ABSTRACT FROM AUTHOR]

In order to increase 1,3-BD yield, ordered mesoporous materials (OMMs) was synthesized and used as supporting materials of heterogeneous catalysts for ethanol conversion into 1,3-BD. To make acidic and basic sites acting as active sites on the surface of catalysts, a moderate (5 wt%) amount of zinc oxide (ZnO) and zirconium oxide (ZrO 2) were impregnated on as-prepared various supporting materials at a time. Prepared catalysts showed different acid-base properties according to used supporting materials. The ordered mesoporous silicas (OMSs) based catalysts were proven to exhibit higher ethanol conversions and 1,3-BD selectivities because they have not only adequate number and strength of acidic sites and basic sites but also very regular mesoporous structure. Especially ZnO-ZrO 2 /KIT-6 revealed a higher 1,3-BD selectivity above 54.0% at ethanol conversion of 82.5% at 400 °C. On the other hand, the selectivity of diethylether (DEE) was grown to over 68% in the case of ordered mesoporous alumina (OMA) based catalyst for example ZnO-ZrO 2 /OMA catalyst with a higher ethanol conversion above 80% at the same temperature. A similar type of catalyst with the ZnO-ZrO 2 /KIT-6, ZnO-ZrO 2 /a-SiO 2 exhibited relatively low ethanol conversion and selectivity toward 1,3-BD. Through these results, it was confirmed that adequate number and strength of strong acidic and basic sites are key factors for full conversion of ethanol to 1,3-BD with well-developed ordered mesoporous structure. Unlabelled Image • The ZnO-ZrO 2 /ordered mesoporous materials (OMMs) were synthesized by soft templating and solution impregnation. • The ZnO-ZrO 2 /OMSs showed better ETB (Ethanol to 1,3-butadiene) performances. • Highly dispersed Zn2+, Zr4+ with balanced acidic and basic sites may be responsible for noticeable ETB activities of the ZnO-ZrO 2 /OMSs. [ABSTRACT FROM AUTHOR]