title: Role of manganese oxide octahedral molecular sieves in styrene epoxidation.
abstract: Manganese oxide octahedral molecular sieves having 2 x 2 tunnel structure (OMS-2) and synthesized by different methods were used for studying styrene oxidation with tert-butyl hydroperoxide (TBHP) as the oxidant. The catalytic activity of the as-synthesized OMS-2 materials was investigated. The physical and chemical properties of the OMS-2 materials are related to their activity in styrene oxidation. This particular study emphasizes the acid-base properties and the porous nature of these materials, and their role in styrene oxidation. Results of styrene oxidation reveal that acidity coupled with high porosity play a crucial role in these catalytic reactions. A desired acidity coupled with pore volume found in OMS-2 synthesized by reflux methods (OMS-2(R)) and high-temperature methods (OMS-2(HT)) produces materials with higher styrene conversion and styrene oxide selectivity when compared with OMS-2 synthesized by solvent free (OMS-2(S)), microwave (OMS-2(MW)), or hydrothermal methods (OMS-2(HY)). Transition metal doped OMS-2 catalysts show better selectivity of styrene oxide when compared to their undoped catalysts.
authors.affiliation: Department of Chemistry, Institute of Material Science, and Department of Chemical Engineering, University of Connecticut, Storrs, Connecticut 06269, USA.
authors.forename: Ruma
authors.initials: R
authors.lastname: Ghosh
authors.forename: Xiongfei
authors.initials: X
authors.lastname: Shen
authors.forename: Josanlet C
authors.initials: JC
authors.lastname: Villegas
authors.forename: Yunshuang
authors.initials: Y
authors.lastname: Ding
authors.forename: Kinga
authors.initials: K
authors.lastname: Malinger
authors.forename: Steven L
authors.initials: SL
authors.lastname: Suib