TY - JOUR
T1 - Enhanced (photo)catalytic activity of Wells-Dawson (H6P2W18O62) in comparison to Keggin (H3PW12O40) heteropolyacids for 2-propanol dehydration in gas-solid regime
AU - Palmisano, Leonardo
AU - Garcia Lopez, Elisa Isabel
AU - Marci', Giuseppe
AU - Pomilla, Francesca Rita
AU - Liotta, Leonarda F.
AU - Pomilla, Francesca Rita
PY - 2016
Y1 - 2016
N2 - Catalytic and photocatalytic 2-propanol dehydration to propene at atmospheric pressure and a temperature range of 60–120 °C were carried out in gas-solid regime by using bare and supported Keggin H3PW12O40 (PW12) and Wells-Dawson H6P2W18O62 (P2W18) heteropolyacids (HPAs). Binary materials were prepared by impregnation of the HPAs on commercial SiO2 and TiO2. The Wells-Dawson was in any case more active than the Keggin heteropolyacid and the differences were enhanced when the supported samples were used. In particular, Wells-Dawson HPA supported on TiO2 and under irradiation showed the highest activity. The HPA species played the key role both in the catalytic and photo-assisted reactions. The acidity of the cluster accounts for the catalytic role, whereas both the acidity and the redox properties of the HPA species were responsible for the increase of the reaction rate in the photo-assisted catalytic reaction. The estimated apparent activation energy resulted always lower for the photocatalytic process than for the catalytic one.
AB - Catalytic and photocatalytic 2-propanol dehydration to propene at atmospheric pressure and a temperature range of 60–120 °C were carried out in gas-solid regime by using bare and supported Keggin H3PW12O40 (PW12) and Wells-Dawson H6P2W18O62 (P2W18) heteropolyacids (HPAs). Binary materials were prepared by impregnation of the HPAs on commercial SiO2 and TiO2. The Wells-Dawson was in any case more active than the Keggin heteropolyacid and the differences were enhanced when the supported samples were used. In particular, Wells-Dawson HPA supported on TiO2 and under irradiation showed the highest activity. The HPA species played the key role both in the catalytic and photo-assisted reactions. The acidity of the cluster accounts for the catalytic role, whereas both the acidity and the redox properties of the HPA species were responsible for the increase of the reaction rate in the photo-assisted catalytic reaction. The estimated apparent activation energy resulted always lower for the photocatalytic process than for the catalytic one.
UR - http://hdl.handle.net/10447/206521
UR - http://www.sciencedirect.com/science/journal/0926860X
M3 - Article
SN - 0926-860X
VL - 528
SP - 113
EP - 122
JO - Applied Catalysis A: General
JF - Applied Catalysis A: General
ER -