VSb3W-Al2O3 catalysts for propane ammoxidation were prepared by the conventional slurry method and new slurry method,namely,the reduction-oxidation slurry method.The effect of preparation methods on the physicochemica...VSb3W-Al2O3 catalysts for propane ammoxidation were prepared by the conventional slurry method and new slurry method,namely,the reduction-oxidation slurry method.The effect of preparation methods on the physicochemical properties of VSb3W-Al2O3 catalysts were studied by N2 adsorption,XRD,XPS and Raman spectroscopy,and their catalytic performance for the ammoxidation of propane to acrylonitrile were tested.Compared with the VSb3W-Al2O3 catalyst prepared by the conventional slurry method,the VSb3W-Al2O3 catalyst prepared by the reduction-oxidation slurry method exhibited better propane conversion and acrylonitrile selectivity.This is due to that the reduction-oxidation treatment was advantageous for obtaining low valence state vanadium and high valence state antimony to form more rutile SbVO4,which is a vital active phase for propane ammoxidation.展开更多
MoVNbTe catalyst has been found to be the most active and selective catalyst in the ammoxidation of propane to ACN, the selective oxidation of propane to acrylic acid and in the oxidative dehydrogenation of ethane to ...MoVNbTe catalyst has been found to be the most active and selective catalyst in the ammoxidation of propane to ACN, the selective oxidation of propane to acrylic acid and in the oxidative dehydrogenation of ethane to ethylene. However, in our previous work, when 0.5 mL of MoVNbTe catalyst prepared using slurry method was tested in the propane ammoxidation to ACN, it only shows 1% conversion of propane with about 55% selectivity to CAN, thus giving only 0.6% yields to ACN. The poor catalyst activity is attributed to insufficient formation of crystalline phases essential for the propane activation process. In an attempt to improve the physicochemical properties of this catalyst, several preparation methods have been used, namely hydrothermal, reflux, changing the solvent and changing the calcinations temperature. The modified catalysts have been characterized using X-Ray Diffraction （XRD） and N2 physisorption （BET）. The MoVNbTe catalyst prepared by hydrothermal method shows a remarkable improvement in the formation of crystalline phases.展开更多
基金support from the National Basic Research Program of China (No.2010CB732300)China Petroleum & Chemical Corporation (No.204061)
文摘VSb3W-Al2O3 catalysts for propane ammoxidation were prepared by the conventional slurry method and new slurry method,namely,the reduction-oxidation slurry method.The effect of preparation methods on the physicochemical properties of VSb3W-Al2O3 catalysts were studied by N2 adsorption,XRD,XPS and Raman spectroscopy,and their catalytic performance for the ammoxidation of propane to acrylonitrile were tested.Compared with the VSb3W-Al2O3 catalyst prepared by the conventional slurry method,the VSb3W-Al2O3 catalyst prepared by the reduction-oxidation slurry method exhibited better propane conversion and acrylonitrile selectivity.This is due to that the reduction-oxidation treatment was advantageous for obtaining low valence state vanadium and high valence state antimony to form more rutile SbVO4,which is a vital active phase for propane ammoxidation.
文摘MoVNbTe catalyst has been found to be the most active and selective catalyst in the ammoxidation of propane to ACN, the selective oxidation of propane to acrylic acid and in the oxidative dehydrogenation of ethane to ethylene. However, in our previous work, when 0.5 mL of MoVNbTe catalyst prepared using slurry method was tested in the propane ammoxidation to ACN, it only shows 1% conversion of propane with about 55% selectivity to CAN, thus giving only 0.6% yields to ACN. The poor catalyst activity is attributed to insufficient formation of crystalline phases essential for the propane activation process. In an attempt to improve the physicochemical properties of this catalyst, several preparation methods have been used, namely hydrothermal, reflux, changing the solvent and changing the calcinations temperature. The modified catalysts have been characterized using X-Ray Diffraction （XRD） and N2 physisorption （BET）. The MoVNbTe catalyst prepared by hydrothermal method shows a remarkable improvement in the formation of crystalline phases.
