title: Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst.
abstract: The light irradiation parameters, including the wavelength spectrum and intensity of light source, can significantly influence a photocatalytic reaction. This study examines the propylene photo-epoxidation over V-Ti/MCM-41 photocatalyst by using artificial sunlight (Xe lamp with/without an Air Mass 1.5 Global Filter at 1.6/18.5 mW·cm(-2)) and ultraviolet light (Mercury Arc lamp with different filters in the range of 0.1-0.8 mW·cm(-2)). This is the first report of using artificial sunlight to drive the photo-epoxidation of propylene. Over V-Ti/MCM-41 photocatalyst, the propylene oxide (PO) formation rate is 193.0 and 112.1 µmol·gcat (-1)·h(-1) with a PO selectivity of 35.0 and 53.7% under UV light and artificial sunlight, respectively. A normalized light utilization (NLU) index is defined and found to correlate well with the rate of both PO formation and C3H6 consumption in log-log scale. The light utilization with a mercury arc lamp is better than with a xenon lamp. The selectivity to PO remains practically unchanged with respect to NLU, suggesting that the photo-epoxidation occurs through the same mechanism under the conditions tested in this study.
authors.affiliation: Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan.
authors.forename: Van-Huy
authors.initials: VH
authors.lastname: Nguyen
authors.affiliation: Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan.
authors.forename: Shawn D
authors.initials: SD
authors.lastname: Lin
authors.affiliation: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Jeffrey Chi-Sheng
authors.initials: JC
authors.lastname: Wu
authors.affiliation: Institute of Environmental Engineering, National Chiao Tung University, Hsin Chu 300, Taiwan.
authors.forename: Hsunling
authors.initials: H
authors.lastname: Bai
keywords: V-Ti/MCM-41 photocatalyst; artificial sunlight; light irradiation effects; photo-epoxidation; ultraviolet (UV) light