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Highlights: [•] The DEC synthesis from CO2, EO and ethanol was attempted for the first time. [•] KI/EtONa as binary catalyst system exhibited higher catalytic performance. [•] This strategy can be successively expanded to terminal epoxides. [•] This method exhibited promising applications on an industrial scale. [ABSTRACT FROM AUTHOR]

Abstract: Lanthanum oxide catalyst prepared by precipitation method and calcined at 600°C exhibited better catalytic activity in the catalytic synthesis of glycerol carbonate from glycerol and urea with TOF up to 1506mmol/g·h. It was proposed that the lanthanum oxide catalyst with more strong basic sites (Td >400°C) exhibited higher catalytic activity. Accordingly, the catalyst containing appropriate amount of La2O2CO3 phase exhibited higher catalytic activity. Moreover, the recycling experiments demonstrated that the catalytic activity can be essentially preserved during the recycling tests investigated. [Copyright &y& Elsevier]

The redox pretreatment of samples is one of the crucial ways of altering the catalytic properties of the supported noble metal materials in many heterogeneous reactions. Here, H2-reducing pretreatment is reported to enhance the thermal stability of Au-CeO2 catalysts prepared by the deposition–precipitation method and calcination at 600 °C for CO oxidation. In order to understand the improved activity and thermal stability, a series of techniques were used to characterize the physico-chemical changes of the catalyst samples. H2 pretreatment may lead to: (i) a strong metal–support interaction (SMSI) between Au nanoparticles (NPs) and CeO2, evidenced by the particular coverage of Au NPs by CeO2, electronic interactions and CO adsorption changes. (ii) the production of surface bicarbonates which can accelerate CO oxidation. As a result, the H2 pretreatment makes the Au NPs more resistant to sintering at high temperature and enhances the CO oxidation activity. Furthermore, this reduction pretreatment strategy may provide a potential approach to enhance the thermal-stability of other supported noble metal catalysts. [ABSTRACT FROM AUTHOR]

Abstract: The non-phosgene carbonylation of 1,6-hexamethylenediamine (HDA) with alkyl carbamates using Y(NO3)3·6H2O as a catalyst and the influence of reaction variables on the yields of dialkyl hexamethylenedicarbamate (HDC) were studied. At 453K and in the presence of 5wt.% Y(NO3)3·6H2O, nearly 100% HDA conversion and 85% dibutyl hexamethylenedicarbamate (BHDC) isolated yield could be achieved when butyl carbamate (BC) was employed as a carbonyl source. During reaction, an induction period was observed, but it almost disappeared by pretreating the catalyst with n-butanol. The FT-IR, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) characterizations of the catalyst showed that some transformation occurred when the catalyst was pretreated with n-butanol or employed during reaction, i.e., part decomposition of Y(NO3)3 to Y2O3, conversion from crystal to amorphous state, changes occurring in chemical state of the active species, as well as some subtle interactions between the catalyst and n-butanol. All these observed changes might be the reason resulting in activation of the catalyst. [Copyright &y& Elsevier]