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A novel La modified copper phyllosilicate nanotubes (Cu-PSNT) were designed for hydrogenation of methyl acetate (MA) to ethanol. La/Cu-PSNT catalysts were prepared by the focus on the formation of unique tubular structure and evolution of copper species by varying La loading. The physicochemical properties and distribution of the copper species were systematically studied through several characterizations. The results showed that the Cu-PSNTs catalyst exhibited superior catalytic activity in comparison with the catalyst prepared by traditional ammonia-evaporation (AE method). Moreover, the addition of La greatly influenced the dispersion of active copper species and the ratio of Cu0/(Cu0 + Cu+) through the strong interplay between copper and lanthanum species. An appropriate amount of La could increase the surface area of active copper and enhance the ability to dissociate H2 on La/Cu-PSNT catalyst, which were essential to increase the activity and stability in this hydrogenation reaction. Novel copper phyllosilicate nanotubes (Cu-PSNT) was fabricated used the hydrothermal method for hydrogenation of methyl acetate to ethanol. The nano-socketed catalyst was felicitously adjusted by doping La. The obtained the 3La/Cu-PSNT catalyst exhibited a high and stable hydrogenation ability due to its proper distribution of copper valence. [ABSTRACT FROM AUTHOR]

Dimethyl carbonate (DMC) is an important environmentally‐friendly organic compound. The need for efficient synthesis of DMC has given a fillip to search for new catalysts and their cost‐effective preparation. In this work, a series of KAlO2/γ‐Al2O3 heterogeneous catalysts were rapidly prepared by impregnation method. These catalysts were characterized by FTIR, XRD, XPS, TG‐MS, ICP‐OES, BET and Hammett acid‐base titration and tested for the synthesis of DMC via transesterification from ethylene carbonate (EC) with methanol. The results demonstrated that KAlO2, as the active species, was produced in large quantities during the calcination process. The catalyst with a calcination temperature of 700 °C and a K2CO3 loading of 45 wt % exhibited the best catalytic activity. The optimum conditions for the process resulted in a catalyst amount of 1.0 wt %, a reaction temperature of 100 °C and a reaction time of 80 min, in which the EC conversion and DMC selectivity were 80.2 % and 98.9 %, respectively. In addition, the TON, TOF and reaction rate were 80.3, 61.2 h−1 and 3.91 gDMC⋅gcat−1⋅min−1. The reusability of the catalyst with best catalytic activity was also studied. [ABSTRACT FROM AUTHOR]