Studies Of The Selective Oxidation Of Propane To Acrolein Over MoVTeNbO/SiO₂ Catalyst Prepared By Sol-gel Method

The selective oxidation of propane to acrolein has attracted much attention due to its economic and scientific terms.As so far,only a few catalysts showed good catalytic performances.In the present work,MoVTeNbO/SiO₂ catalysts were prepared by sol-gel method,which showed good catalytic performance for the selective oxidation of propane to acrolein.The effects of catalyst loading,composition and preparation conditions on the catalytic performance of MoVTeNbO/SiO₂ catalyst were investigated.Furthermore,The effects of preparation methods and Te loading on the structure,redox and acid-base properties as well as the catalytic performance of catalysts were also investigated.The main results are summarized as follows:1.Highly dispersed MoVTeNbO/SiO₂ catalysts prepared by sol-gel method showed high activity and selectivity for the selective oxidation of propane to acrolein. The best result was obtained on the catalyst(atomic ratio:(Mo+V+Te+Nb)/Si=2%, Mo/V/Te/Nb=1/0.3/0.23/0.1)with the 45.9%selectivity of acrolein at the propane conversion of 39.9%.2.In comparison with the catalysts prepared by impregnation method,the MoVTeNbO/SiO₂ catalysts prepared by sol-gel method showed higher surface area and lower surface atomic concentration,which lead to high dispersion and isolation of the active species on the support.Furthermore,the results showed that the reducibility of catalysts was improved,and the Bronsted acid site concentration of catalysts was decreased on the catalysts prepared by sol-gel method.Therefore,the catalysts prepared by sol-gel method showed good catalytic performance for the selective oxidation of propane to acrolein.3.The characterization results showed that the addition of Te to the MoVNbO/SiO₂ catalysts enhanced the specific surface acidity,improved the reducibility of the supported catalyst,and enhanced the conversion of propene to acrolein,thus improving the performance of the catalyst for propane selective oxidation to acrolein.