TY - JOUR
T1 - Direct gas-phase photocatalytic epoxidation of propylene with molecular oxygen by photocatalysts
AU - Nguyen, Van Huy
AU - Chan, Hsiang Yu
AU - Wu, Jeffrey C.S.
AU - Bai, Hsun-Ling
PY - 2012/1/1
Y1 - 2012/1/1
N2 - The photocatalytic epoxidation of propylene by molecular oxygen is one of the best methods to produce propylene oxide (PO) from the environmental viewpoints. The key is using photo-energy to achieve high PO selectivity and yield at mild conditions. A series of photocatalysts including SiO 2, TiO 2, V-Ti/MCM-41, V 2O 5/SiO 2, Au/TiO 2 and TS-1, were used to evaluate their performance in the photo-epoxidation. The photocatalytic epoxidation of propylene was carried out in the gas mixture of C 3H 6:O 2:N 2=1:1:18 at atmospheric pressure. In addition to PO, other products, such as propionaldehyde, acetone, acetaldehyde, ethanol and methanol, were detected. The results indicated that the most favorable photocatalysts for photocatalytic epoxidation were silicates supported group. The highest PO formation rate of 114μmolgcat -1h -1 with selectivity of 47% was obtained over V-Ti/MCM-41 on stream after 4h at 50°C and atmospheric pressure under UVA irradiation of 0.2mW/cm 2. In addition, the selectivity of products was very stable on stream. A possible reaction mechanism was proposed based on the knowledge of species presented during the photocatalytic reaction.
AB - The photocatalytic epoxidation of propylene by molecular oxygen is one of the best methods to produce propylene oxide (PO) from the environmental viewpoints. The key is using photo-energy to achieve high PO selectivity and yield at mild conditions. A series of photocatalysts including SiO 2, TiO 2, V-Ti/MCM-41, V 2O 5/SiO 2, Au/TiO 2 and TS-1, were used to evaluate their performance in the photo-epoxidation. The photocatalytic epoxidation of propylene was carried out in the gas mixture of C 3H 6:O 2:N 2=1:1:18 at atmospheric pressure. In addition to PO, other products, such as propionaldehyde, acetone, acetaldehyde, ethanol and methanol, were detected. The results indicated that the most favorable photocatalysts for photocatalytic epoxidation were silicates supported group. The highest PO formation rate of 114μmolgcat -1h -1 with selectivity of 47% was obtained over V-Ti/MCM-41 on stream after 4h at 50°C and atmospheric pressure under UVA irradiation of 0.2mW/cm 2. In addition, the selectivity of products was very stable on stream. A possible reaction mechanism was proposed based on the knowledge of species presented during the photocatalytic reaction.
KW - Epoxidation
KW - MCM-41
KW - Molecular oxygen
KW - Photocatalysis
KW - Propylene oxide
KW - TiO
UR - http://www.scopus.com/inward/record.url?scp=84155186327&partnerID=8YFLogxK
U2 - 10.1016/j.cej.2011.11.003
DO - 10.1016/j.cej.2011.11.003
M3 - Article
AN - SCOPUS:84155186327
VL - 179
SP - 285
EP - 294
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
SN - 1385-8947
ER -