Alkali promoted selective epoxidation of styrene to styrene oxide using TS-1 catalyst

The epoxidation of styrene was carried out over titanium silicalite (TS-1) and an alkali (sodium hydroxide) in the reaction medium. This system gave a very high TOF (>200 h(-1)) and selectivity to styrene oxide (>92%). It was found by EPR characterization that the local coordination of Ti centers is transformed from five fold to six fold in presence of NaOH. Also, further isomerization of styrene oxide to phenylacetaldehyde is nearly suppressed by NaOH, thereby increasina the styrene oxide selectivity remarkably. (C) 2003 Elsevier B.V. All rights reserved.