TY - JOUR
T1 - Structure and catalytic properties of vanadium oxide supported on mesocellulous silica foams (MCF) for the oxidative dehydrogenation of propane to propylene
AU - Liu, Yong Mei
AU - Feng, Wei Liang
AU - Li, Ting Cheng
AU - He, He Yong
AU - Dai, Wei Lin
AU - Huang, Wei
AU - Cao, Yong
AU - Fan, Kang Nian
PY - 2006/4/1
Y1 - 2006/4/1
N2 - A series of vanadium containing mesocellular silica foams (MCF) featuring a well-defined three-dimensional (3D) mesoporosity with ultralarge mesopores were studied with regard to their performance in the oxidative dehydrogenation (ODH) of propane. Catalysts supported on two-dimensional hexagonally ordered siliceous SBA-15 and MCM-41, as well as conventional amorphous silica, were also examined. The dispersity and the nature of the vanadium oxide species were characterized by means of DRIFTS, Raman spectroscopy, DR UV-vis, and H 2-TPR. Textural, SAXS, and TEM results indicate that the characteristic mesocellular structural features of MCFs are preserved after the vanadium incorporation. Spectroscopic measurements show that vanadium exists mainly in a tetrahedral environment in dehydrated V-MCF catalysts with V content <4.2 wt%, indicating that a very high surface concentration of isolated or low-polymeric VOx species could be achieved on the present V-MCF systems. The MCF-supported vanadia catalysts exhibit much higher propane conversion and propylene productivity than their conventional V-SBA, V-MCM, and V-SiO2 counterparts in the ODH of propane, demonstrating that apart from the active redox sites, internal molecular transport in mesopores of the catalyst also plays an important role in the gas-phase selective oxidation reactions.
AB - A series of vanadium containing mesocellular silica foams (MCF) featuring a well-defined three-dimensional (3D) mesoporosity with ultralarge mesopores were studied with regard to their performance in the oxidative dehydrogenation (ODH) of propane. Catalysts supported on two-dimensional hexagonally ordered siliceous SBA-15 and MCM-41, as well as conventional amorphous silica, were also examined. The dispersity and the nature of the vanadium oxide species were characterized by means of DRIFTS, Raman spectroscopy, DR UV-vis, and H 2-TPR. Textural, SAXS, and TEM results indicate that the characteristic mesocellular structural features of MCFs are preserved after the vanadium incorporation. Spectroscopic measurements show that vanadium exists mainly in a tetrahedral environment in dehydrated V-MCF catalysts with V content <4.2 wt%, indicating that a very high surface concentration of isolated or low-polymeric VOx species could be achieved on the present V-MCF systems. The MCF-supported vanadia catalysts exhibit much higher propane conversion and propylene productivity than their conventional V-SBA, V-MCM, and V-SiO2 counterparts in the ODH of propane, demonstrating that apart from the active redox sites, internal molecular transport in mesopores of the catalyst also plays an important role in the gas-phase selective oxidation reactions.
KW - Internal molecular transport
KW - Mesocellular silica foams
KW - Oxidative hydrogenation of propane
KW - Propylene
KW - Supported vanadia catalyst
UR - http://www.scopus.com/inward/record.url?scp=33644867704&partnerID=8YFLogxK
U2 - 10.1016/j.jcat.2005.12.028
DO - 10.1016/j.jcat.2005.12.028
M3 - 文章
AN - SCOPUS:33644867704
SN - 0021-9517
VL - 239
SP - 125
EP - 136
JO - Journal of Catalysis
JF - Journal of Catalysis
IS - 1
ER -