ZnO/SiO\-2 and ZnO\|SiO\-2 catalysts were prepared by the impregnation and sol\|gel method, respectively. The characterization of the catalysts by XPS and FTIR indicated that much "free" zinc oxide and unrea...ZnO/SiO\-2 and ZnO\|SiO\-2 catalysts were prepared by the impregnation and sol\|gel method, respectively. The characterization of the catalysts by XPS and FTIR indicated that much "free" zinc oxide and unreacted Si\_OH existed on the surface of ZnO/SiO\-2 sample. As for ZnO\|SiO\-2 sol\|gel catalyst, the corresponding phenomena were not observed. The prepared samples were also used as the catalysts for decomposition of 2\|butanol. A high selectivity for dehydrogenation was observed over the supported catalyst. However, a high selectivity for dehydration was shown over the ZnO\|SiO\-2 sol\|gel catalyst. The opposite selectivity for dehydration or dehydrogenation observed over the two kinds of catalysts may be just because of the different surface structures of the catalysts.展开更多
The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed t...The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed to investigate the states of several atoms during stepwise supporting catalyst for clarifying the mechanism.The results showed two possible mechanisms of active catalytic sites on the composite carrier:the catalytic sites bridged through MAO on the inorganic silica gel;on contrary,the catalytic sites bridging with carbonyls of amide formed in the composite.展开更多
文摘ZnO/SiO\-2 and ZnO\|SiO\-2 catalysts were prepared by the impregnation and sol\|gel method, respectively. The characterization of the catalysts by XPS and FTIR indicated that much "free" zinc oxide and unreacted Si\_OH existed on the surface of ZnO/SiO\-2 sample. As for ZnO\|SiO\-2 sol\|gel catalyst, the corresponding phenomena were not observed. The prepared samples were also used as the catalysts for decomposition of 2\|butanol. A high selectivity for dehydrogenation was observed over the supported catalyst. However, a high selectivity for dehydration was shown over the ZnO\|SiO\-2 sol\|gel catalyst. The opposite selectivity for dehydration or dehydrogenation observed over the two kinds of catalysts may be just because of the different surface structures of the catalysts.
文摘The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed to investigate the states of several atoms during stepwise supporting catalyst for clarifying the mechanism.The results showed two possible mechanisms of active catalytic sites on the composite carrier:the catalytic sites bridged through MAO on the inorganic silica gel;on contrary,the catalytic sites bridging with carbonyls of amide formed in the composite.
