Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic performance.The composition,structure and copper valence state were characterized by means of B...Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic performance.The composition,structure and copper valence state were characterized by means of BET,XRD,XPS,FTIR,N2O-titration.It was found that the Cu/SiO2 prepared by ammoniaevaporation（AE） method had much higher TOF value than that prepared by wetness-impregnation（WI）with the same THF selectivity.The higher TOF value was attributed to the coexistence of Cu^＋ and Cu^0species in the activated AE-Cu/SiO2.while only Cu° species existing in the activated Wl-Cu/SiO2.Researches suggest that Cu^＋ can adsorb and polarize the C=0 bond of DMM.It is concluded that Cu°could be the main active site and the synergistic effect between Cu^0 and Cu^＋ could contribute to hydrogenation of DMM to THF.展开更多
基金Funding for the present study from the National Key Basic Research Program of China(973 Program,No.2011CB710800)National Natural Science Foundation of China(No.NSFC21406199)
文摘Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic performance.The composition,structure and copper valence state were characterized by means of BET,XRD,XPS,FTIR,N2O-titration.It was found that the Cu/SiO2 prepared by ammoniaevaporation（AE） method had much higher TOF value than that prepared by wetness-impregnation（WI）with the same THF selectivity.The higher TOF value was attributed to the coexistence of Cu^＋ and Cu^0species in the activated AE-Cu/SiO2.while only Cu° species existing in the activated Wl-Cu/SiO2.Researches suggest that Cu^＋ can adsorb and polarize the C=0 bond of DMM.It is concluded that Cu°could be the main active site and the synergistic effect between Cu^0 and Cu^＋ could contribute to hydrogenation of DMM to THF.
