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Catalytic transformation of CO2 into chemicals in large demand such as ethanol has attracted much research attention under the background of establishing carbon-neutral societies. Supported Rh cata...

Recent studies demonstrate that bifunctional catalysts composed of metal oxide and zeolite can effectively control the hydrocarbon distribution in syngas conversion. In this effort, a set of eight silicoaluminophosphate (SAPO) zeolites with different topology structures are synthesized and integrated with a binary ZnAlO oxide for syngas conversion. The effects of micropore window size and cage size of SAPO zeolites, and reaction conditions on the hydrocarbon distribution are preliminarily investigated. It was found that the hydrocarbon distribution is primarily determined by the window size of SAPO zeolites, and a volcano trend was observed between the chain length of hydrocarbon products and the window sizes. The cage size of zeolites and reaction conditions only modifies the hydrocarbon distribution in a narrow range of chain length. The effect of zeolite topology on the hydrocarbon distribution in syngas conversion is overall in line with that in methanol conversion. These findings provide an efficient strategy to increase the selectivity of an individual hydrocarbon product in syngas conversion, such as ethylene, propylene, butenes, iso-butane and C5–C11 iso-paraffins.

Maximizing the use of palladium without compromises in catalytic activity and stability in the combustion of methane is extremely challenging due to the harsh operation conditions. To achieve this goal, a series of core-shell-structured catalysts with different amounts of palladium nanoparticles confined in hydrophobic silicalite-1 (Pd@S-1) was designed. Unexpectedly, a volcanic trend between catalytic activity and palladium loading was found as the loading increased from 0.3 wt% to 1.6 wt%, among which the 0.6 wt%Pd@S-1 exhibited the highest catalytic activity with a complete combustion temperature of 380 °C. Besides, the 0.6 wt%Pd@S-1 showed an ultrahigh stability in the high temperature applications due to the spatial confinement of palladium inside the rigid zeolite matrix. Moreover, owing to the hydrophobicity of the pure silica zeolite, the Pd@S-1 could selectively hinder the diffusion of water vapor into the palladium sites, leading to the outstanding water-resistance ability.