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Stable F-T-based catalyst development in direct CO hydrogenation to higher alcohols is still a challenge at present. In this study, CuFe/SiO2 catalysts with a SiO2 support treated with a piranha solution were prepared and evaluated in a long-term reaction. The treated catalyst showed higher total alcohols’ selectivity and great stability during a reaction of more than 90 h. It was found that the treatment with the piranha solution enriched the surface hydroxyl groups on SiO2, so that the Cu–Fe active components could be firmly anchored and highly dispersed on the support, resulting in stable catalytic performance. Furthermore, the in situ DRIFTS revealed that the adsorption strength of CO on Cu+ on the treated catalyst surface was weakened, which made the C-O bond less likely to be cleaved and thus significantly inhibited the formation of hydrocarbon products. Meanwhile, the non-dissociated CO species were obviously enriched on the Cu0 surface, promoting the formation of alcohol products, and thus the selectivity of total alcohols was increased. This strategy will shed light on the design of supported catalysts with stabilized structures for a wide range of catalytic reactions.

Vapor phase carbonylation of methanol was investigated over Ni-Pd/AC catalyst under the conditions of 260°C, 1.5 MPa, CO/CH 3 OH/CH 3 I(molar ratio)20/19/1, W/F =7.5 g cat ·h·mol −1 . The structure and surface property of the fresh and deactivated Ni-Pd/AC catalysts were characterized by BET specific surface area, Pyrolysis-FTIR (Py-FTIR) and XPS. It was found that the deactivation at the primary step appeared to be consistent with a strong adsorption of reaction products that plugged the catalyst pores and led to a diffusion limitation. With the proceeding of the reaction, the carbonylation active site Ni migrated gradually and enriched on the catalyst surface, resulting in easy carbon deposition, which enhanced the deactivation of the catalyst. Further investigation revealed that the carbon deposited on the catalyst surface has graphite structure or is similar to graphite structure.

Synthesis of iso-alkanes from carbon dioxide hydrogenation was investigated over Fe–Zn–M/Zeolite composite catalysts. The effects of different promoter metals (M=Cr, Mn, Zr, Al, La) and zeolites on the performance of carbon dioxide hydrogenation were studied. The structure and the acidity of zeolites were investigated by IR, NH 3 -TPD and Py-IR. It was found that Zr had a better promotional effect than other additive metal components for the iron-based catalyst. The catalyst had different catalytic performances with different zeolites and the distribution of hydrocarbon products was influenced by the acidity of the zeolite. The HY zeolite was the most effective one for iso-alkane synthesis due to its medium-strength and strong acid sites, which could be observed through temperature-programmed desorption of ammonia (NH 3 -TPD).